Category Archives: Quantum Physics

KINGSTON, R.I. Sept. 21, 2023 As part of its quantum computing initiative, the University of Rhode Island will welcome Charles Robinson, worldwide lead of IBMs Quantum Safe Team, to campus for a public lecture. Robinson will give a talk titled From North Philly to Quantum Computing: Lessons Learned Along the Way on Monday, Sept. 25, at 4 p.m. in Edwards Hall.

The path from North Philly to being IBMs worldwide leader of the Quantum Safe Team has not been a straight line, Robinson said. In my presentation, I want to highlight the types of obstacles that I overcame and that many of you will likely experience. More important are the strategies and attitudes that you can employ to overcome hurdles, survive, and excel. No one size fits all but, at the end of the day, there is always a path forward.

As leader of IBMs Quantum Safe Team, Robinson works to develop and implement technologies that will protect data in a post-quantum world. Quantum computerscomputer systems that harness the behavior of matter at the tiniest scalesare expected to be able to perform calculations in seconds that would take years on even the most powerful computers operating today. While that dramatic increase in computing power promises to be an enormous boon for science and industry, it comes with a problem: Most of the encryption schemes currently used to secure data will be rendered obsolete as soon as large-scale quantum systems come online.

The Quantum Safe Team develops new encryption algorithms that will remain robust in the face of quantum computing power. The team also works with governments and companies all over the world to help them prepare for the coming quantum revolution. Doing so is critical to protecting credit card numbers, bank account information, medical records, and all other sensitive information that can be accessed via the internet.

Len Kahn, chair of the URI Department of Physics, says that quantum security represents an immediate area of focus in the coming quantum computing revolution.

All of the data thats on the internet now needs to be secured before quantum computers come online, Kahn said. We need to think about training people now to work on this and other critical problems, which is part of what were hoping to do with the quantum computing initiative at URI.

Kahn says that having Robinson speak at URI is important in part because of his unconventional path to worldwide leadership in the quantum field, as well as his efforts to make sure quantum information science is a career path available to anyone.

Robinson trained as a corpsman in the Navy before transitioning to engineering in community college. He went on to graduate from Howard University and receiving a graduate degree from Johns Hopkins. After working as an engineer and software developer for several large firms, Robinson began working extensively with the defense and intelligence community on issues related to communications and computing. He became the worldwide leader of the Quantum Safe Team in 2020.

Robinson has also worked extensively with Howard Universitys IBM-HBCU QuantumCenter, which aims to prepare and developtalent from historically Black colleges and universities for the quantum future.

The quantum revolution represents both tremendous challenges and opportunities, Kahn said. If were going to meet these challenges and create the workforce of tomorrow, well need to engage communities that have been traditionally underrepresented in scientific fields. Charles is a knowledgeable resource, and we continue to benefit from his experience.

The event is sponsored by the Office of the Provost, the Academic Enhancement Center, and the Department of Physics.

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Leader of IBM's Quantum Safe Team to speak at URI - University of Rhode Island

51 Faculty of Physics Startdate:01.11.2023|Working hours:30|Collective bargaining agreement:48 VwGr. B1 Grundstufe (praedoc) Limited until:30.04.2027 Reference no.:1347

How does a quantum object gravitate?, How far can we push massive objects into the quantum regime?, How well can we measure gravity of microscopic systems?. Such questions and their implications for the foundations of physics are the driving force behind our research. You will be part of our team and develop new ideas, technologies and experiments to provide new insights on macroscopic quantum physics, on gravity at small scales and, in the long run, on the phenomenology of the gravity-quantum interface in table-top experiments.

Your personal sphere of influence:

As a university assistant (praedoc) on this 3.5-year position, you will be part of the Aspelmeyer group, and you will be exploring fundamentals and applications of quantum entanglement in levitated solid-state platforms.

The main research activities of our group include quantum optical control of levitated solid-state objects, the exploration of their quantum properties for fundamental questions and novel quantum technology platforms, as well as precision measurements of ultra-weak gravitational forces. Our main motivation is to explore the interface between quantum physics and gravity with new experimental platforms.

Our Team is part of the Quantum Optics, Quantum Nanophysics and Quantum Information group of the Faculty of Physics.

We are member of the Vienna Center for Quantum Science and Technology (VCQ), one of the largest quantum hubs in Europe, and of the Austrian Cluster of Excellence (quantA), advancing basic research in quantum sciences, aiming to expand the frontiers of knowledge and thus being the engine for future innovations.

You will also benefit from being fellow of the Vienna Doctoral School in Physics (VDSP), being part of a thriving community with more than 100 quantum scientists on premise, about 300 quantum researchers in Vienna.

The Aspelmeyer group explores the interface between quantum physics and gravity in experiments, in particular involving quantum objects as sources of gravity. On the quantum side, we explore the extreme regime of motional quantum states of solids and their interactions to understand how to maximize mass, delocalization, and coherence time in quantum experiments. On the gravity side, we explore the extreme regime of gravitational phenomena of miniature source masses to understand how to isolate gravity from all other interactions on a microscopic scale. Together with colleagues from theory we try to formulate meaningful questions that help to establish decisive experimental tests of the quantum nature of gravity.

Your future tasks:

You will actively participate in research, teaching & administration. This means:

This is part of your personality:

What we offer:

Inspiring working atmosphere:You are a part of an international academic team in a healthy and fair working environment.

Good public transport connections:Your workplace in the center of beautiful Vienna is easily accessible by public transport.

Potential for development:Success in life depends on what you make of it, but if you are ambitious and successful, there are plenty of opportunities to connect you to all relevant top research groups in the world.

Internal further training & Coaching:The Vienna Doctoral School as well as the department of human resources offer plenty of opportunities to grow your skills in over 600 courses to choose from free of charge.

Fair salary:The basic salary of EUR 2,457.00 (30h, 14x p.a.) increases if we can credit professional experience. The employment duration is 4 years. Initially limited to 1.5 years, the employment relationship is automatically extended to3.5 yearsif the employer does not terminate it within the first 12 months by submitting a non-extension declaration.

Equal opportunities for everyone:We look forward to diverse personalities in the team!

It is that easy to apply:

If you have any questions, please contact:

Markus Aspelmeyer

markus.aspelmeyer@univie.ac.at

We look forward to new personalities in our team! We lay special emphasis on increasing the number of women in senior and in academic positions among the academic and general university staff and therefore expressly encourage qualified women to apply. In order to increase the percentage of women in Physics, the announced position is open to qualified female candidates only.

University of Vienna. Space for personalities. Since 1365.

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Application deadline:08/10/2023

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University Assistant Predoctoral, Physics job with UNIVERSITY OF ... - Times Higher Education

A snapshot of the ab initio molecule dynamics simulations at 753 degrees Kelvin, showing the polarized titanium oxide bonding with local tetragonal structures in various orientations, which depict the local 90 and 180 degree domain walls. Credit: Courtesy Zi-Kui Liu

The universe naturally gravitates towards disorder, and only through the input of energy can we combat this inevitable chaos. This idea is encapsulated in the concept of entropy, evident in everyday phenomena like ice melting, fires burning, and water boiling. However, zentropy theory introduces an additional layer to this understanding.

This theory was developed by a team led by Zi-Kui Liu, the distinguished Dorothy Pate Enright Professor of Materials Science and Engineering at Penn State. The Z in zentropy is derived from the German term Zustandssumm, which translates to the sum over states of entropy.

Alternatively, Liu said, zentropy may be considered as a play on the term zen from Buddhism and entropy to gain insight on the nature of a system. The idea, Liu said, is to consider how entropy can occur over multiple scales within a system to help predict potential outcomes of the system when influenced by its surroundings.

Liu and his research team have published their latest paper on the concept, providing evidence that the approach may offer a way to predict the outcome of experiments and enable more efficient discovery and design of new ferroelectric materials. The work, which incorporates some intuition and a lot of physics to provide a parameter-free pathway to predicting how advanced materials behave, was published inScripta Materialia.

Ferroelectrics have unique properties, making them valuable for a variety of applications both now and in developing materials, researchers said. One such property is spontaneous electric polarization that can be reversed by applying an electric field, which facilitates technologies ranging from ultrasounds to ink-jet printers to energy-efficient RAM for computers to the ferroelectric-driven gyroscope in smartphones that enable smooth videos and sharp photos.

To develop these technologies, researchers need to experiment to understand the behavior of such polarization and its reversal. For efficiencys sake, the researchers usually design their experiments based on predicted outcomes. Typically, such predictions require adjustments called fitting parameters to closely match real-world variables, which take time and energy to determine. But zentropy can integrate top-down statistical and bottom-up quantum mechanics to predict experimental measures of the system without such adjustments.

Of course, at the end of the day, the experiments are the ultimate test, but we found that zentropy can provide a quantitative prediction that can narrow down the possibilities significantly, Liu said. You can design better experiments to explore ferroelectric material and the research work can move much faster, and this means you save time, energy, and money and are more efficient.

While Liu and his team have successfully applied zentropy theory to predict the magnetic properties of a range of materials for various phenomena, discovering how to apply it to ferroelectric materials has been tricky. In the current study, the researchers reported finding a method to apply zentropy theory to ferroelectrics, focusing on lead titanate. Like all ferroelectrics, lead titanate possesses electric polarization that can be reversed when external electric fields, temperature changes, or mechanical stress is applied.

As an electric field reverses electric polarization reverses, the system transitions from ordered in one direction to disordered and then to ordered again as the system settles into the new direction. However, this ferroelectricity occurs only below a critical temperature unique to each ferroelectric material. Above this temperature, ferroelectricity the ability to reverse polarization disappears and paraelectricity the ability to become polarized emerges. The change is called the phase transition. The measurement of those temperatures can indicate critical information about the outcome of various experiments, Liu said. However, predicting the phase transition prior to an experiment is nearly impossible.

No theory and method can accurately predict the free energy of the ferroelectric materials and the phase transitions prior to the experiments, Liu said. The best prediction of transition temperature is more than 100 degrees away from the experiments actual temperature.

This discrepancy arises due to the unknown uncertainties in models, as well as fitting parameters that could not consider all salient information affecting the actual measurements. For example, an often-used theory characterizes macroscopic features of ferroelectricity and paraelectricity but does not consider microscopic features such as dynamic domain walls boundaries between regions with distinct polarization characteristics within the material. These configurations are building blocks of the system and fluctuate significantly with respect to temperature and electric field.

In ferroelectrics, the configuration of electric dipoles in the material can change the direction of polarization. The researchers applied zentropy to predict the phase transitions in lead titanate, including identifying three types of possible configurations in the material.

The predictions made by the researchers were effective and in agreement with observations made during experiments reported in the scientific literature, according to Liu. They used publicly available data on domain wall energies to predict a transition temperature of 776 degrees Kelvin, showing a remarkable agreement withthe observed experimental transition temperature of 763 degrees Kelvin. Liu said the team is working on further reducing the difference between predicted and observed temperatures with better predictions of domain wall energies as a function of temperature.

This ability to predict transition temperature so closely to the actual measurements can provide valuable insights into the physics of ferroelectric material and help scientists to better their experimental designs, Liu said.

This basically means you can have some intuitions and a predictive approach on how a material behaves both microscopically and macroscopically before you conduct the experiments, Liu said. We can start predicting the outcome accurately before the experiment.

Along with Liu, other researchers in the study from Penn State include Shun-Li Shang, research professor of materials science and engineering; Yi Wang, research professor of materials science and engineering; and Jinglian Du, research fellow in materials science and engineering at the time of the study.

Reference: Parameter-free prediction of phase transition in PbTiO3 through combination of quantum mechanics and statistical mechanics by Zi-Kui Liu, Shun-Li Shang, Jinglian Du and Yi Wang, 20 April 2023, Scripta Materialia. DOI: 10.1016/j.scriptamat.2023.115480

The Department of Energys Basic Energy Sciences program supported this research.

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Zentropy A New Theory That Could Transform Material Science - SciTechDaily

A team of researchers studying the quantum realm say they have observed an otherworldly mirror universe through the eye of a decaying monopole that is eerily reminiscent of the mirror universe written about by author Lewis Carroll in his Alices Adventures in Wonderland.

Dubbed an Alice ring in honor of Carrolls mirror universe, these fleeting, quantum world events may help to unravel the mysteries of the quantum realm.

In quantum physics, monopoles are the proposed counterpart to dipoles, which have a positive and negative charge at opposing ends, just like a conventional magnet. In contrast, the monopole is only negatively or positively charged.

For decades, scientists have theorized how an actual magnetic monopole might decay, with the most common theory being that it would create a brief, fleeting ring-like structure that might open the door to an alternate mirror universe. As noted, the mirror universe revealed by these decaying rings reminded theorists of the mirror universe in Lewis Carrols Alices Adventures in Wonderland, where everything is the opposite of the real world.

Such theoretical Alice rings have remained particularly elusive for decades. But now, a team of researchers who have been studying the phenomenon for years say they have spotted these structures in nature for the first time ever. And as they suspected, Alice rings may indeed be a portal to what they describe as an otherworldly mirror universe.

The hunt for a real-world Alice ring involved a years-long collaboration between Professor Mikko Mttnen of Aalto University and Professor David Hall from Amherst College. In fact, their first discovery on the road to Carrolls mirror universe took place in 2014, when the duo successfully proved the existence of an analog of a quantum monopole.In 2015, they actually isolated a quantum monopole, and then in 2017 actually observed one decaying into the other. Still, it wasnt until their latest research that they witnessed the appearance of the doorway to the mirror universe known as the elusive Alice ring.

This was the first time our collaboration was able to create Alice rings in nature, which was a monumental achievement, Mttnen said.

According to the press release announcing this once-in-a-career feat, the research team, which was aided by Ph.D. candidate Alina Blinova, manipulated a gas of rubidium atoms prepared in a nonmagnetic state near absolute zero temperature. Then, operating under these extreme conditions, the researchers were able to create a monopole by steering a zero point of a three-dimensional magnetic field into the quantum gas. As previously theorized, the result was a perfectly formed Alice ring.

Notably, the researchers point out that Alice rings only last for a few milliseconds, as they are extremely fragile. This means that when a magnetic monopole is exposed to the slightest external force, it immediately decays into an Alice ring.

Think of the monopole as an egg teetering at the top of a hill, Mttnen said. The slightest perturbations can send it crashing down. In the same way, monopoles are subject to noise that triggers their decay into Alice rings.

Perhaps even more astonishing, and as the longtime collaborators had hoped, their Alice ring seemed to offer a glimpse into a mirror universe just like Carrolls.

From a distance, the Alice ring just looks like a monopole, but the world takes a different shape when peering through the centre of the ring, Hall said.

It is from this perspective that everything seems to be mirrored, as if the ring were a gateway into a world of antimatter instead of matter, Mttnen added.

Published in the journal Nature Communications, the researchers say that the verified observation of an Alice ring in the real world could one day lead to a better understanding of quantum physics. However, there is still no indication whether or not it will lead to attending a tea party with a mad hatter.

Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.

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Researchers Studying the Quantum Realm Observe Alice in ... - The Debrief

The business of artificial intelligence is booming. In all walks of life, youd be hard pressed not to find some sort of AI in what you do daily. It may be as simple as pulling up directions on your phone or as complicated as touching up photos with generative AI programs.

For Augusta University graduate Philip Dyche, hes trying to capitalize on the growing industry.Dyche is starting up a business called DocuSight AI that features three products. One, called PDFchat Pro, is designed for professionals. This AI tool is useful for professionals who need to navigate through complex documents quickly and efficiently. Businesses can now upload large files and then allow AI to help extract exactly what the business may need to function at a higher level.

The second product is called StudyBud AI, which is similar to the first, but is designed for educational purposes. Students can upload their textbooks or other student materials, and artificial intelligence will learn the content, simplify complex subjects and provide insightful answers to a students questions. Dyche feels this is a game-changer for students who want to optimize their study potential. He sees the demands on students, especially those already working full-time, and knows this AI tool can help them out.

The final product is called AgapeChat AI. Agape translates to love in Hebrew. During a humorous conversation with his father, an idea was born to upload different versions of the Bible. Users can ask questions to their selection of pre-uploaded Bibles and receive immediate, in-context responses. This can enhance the faith exploration journey for spiritual seekers and religious educators, Dyche said.

Its an impressive leap for this 26-year-old who graduated in 2021 with a physics degree from Augusta Universitys College of Science and Mathematics, complemented by minors in math and business.

After contributing as a capacity planning analyst at Southern Company Gas, Dyche is set to embark on a new journey as a nuclear physicist with Southern Nuclear starting in October. Unfazed by the challenges and ever confident, he is optimistic about the road ahead.

I am very positive about things. I try to not have a lot of things hold me back, said Dyche.

He also wanted to get in on the AI business early, so he can be positioned well for the future.

Thats exactly like I was thinking. Its like having the chance to invest in Google when it was just a startup. If you got in on that early, youd be set for life, said Dyche.

Dyche came to Augusta University originally for the pre-dental program, but switched to the physics program upon hearing more about it. It led to opening the doors to the nuclear field along with a number of opportunities.

The influence of AU, the bond with my fraternity brothers, the chats with other students and the support from the staff all pushed me. I wanted to do big things after college, and now its like Ive strapped into a rocket and Im just taking off.

While physics delved into topics like electrodynamics, quantum physics and intricate math formulas that might seem like rocket science, its true lesson was profound yet simple, Dyche said. It taught me that even the most complicated issues can be dissected into smaller, more manageable parts. This approach isnt just academic; its a valuable skill in the business world, making complex tasks more approachable.

It got him thinking about artificial intelligence. He said its not easy to find a tutor for quantum physics or electrodynamics. He thought if you could sit down and talk to your textbook, that would serve as a guide to help with the studying and understanding of difficult topics.

He saw how the technology industry was starting to boom with AI. Since he was already coding, he began to play around more with it and saw there was a gap in the workforce with file and document analysis. That was sort of the light bulb moment for Dyche to develop DocuSight AI.

There are a ton of apps out there to check your files, but imagine digging through a massive 400- to 500-page PDF, just trying to find a warranty or product ID. Its like searching for a needle in a haystack. Thats where DocuSight AI can be a game changer. Its like having an assistant in your pocket. You ask, and in a snap, you get your answer. I just couldnt ignore such a glaring gap and the chance to make things easier.

Along with his studies at Augusta University, Dyche also served as president of Pi Kappa Phi fraternity. Hes still using those connections to further his business venture.

One of my fraternity brothers, Alex Rountree, is working for the national organization, so hes going to be at different schools throughout the nation. Hes going to be helping me market my company to all those different schools while hes out there recruiting for the fraternity men, added Dyche.

Read more: Criminal justice grad retires his paws as Augusta University mascot

As a physics student, he credits Joseph Hauger, PhD, Fuller E. Callaway Chair in Physics, for helping him get where he is today.

He greatly impacted many of my post-college endeavors. Not only is hes an exceptional teacher, hes also a genuine leader. His positive influence reaches many students. It was Hauger who introduced me to coding and robotics.

Besides working for Southern Nuclear and getting DocuSight AI off the ground, Dyche is also pursuing a Master in Business Administration. He has a quest for knowledge that shows no sign of slowing down, and he gives a lot of credit to the AU influence on his career.

Honestly, I never saw myself being in this spot so soon after walking across the graduation stage. It feels like just yesterday. The influence of AU, the bond with my fraternity brothers, the chats with other students and the support from the staff all pushed me. I wanted to do big things after college, and now its like Ive strapped into a rocket and Im just taking off.

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In a breakthrough in quantum information storage, researchers have developed a method to translate electrical quantum states into sound and vice versa, utilizing phonons.

Quantum computing, just like traditional computing, requires a method to store the information it uses and processes. In the computer youre using right now, informationwhether it be photos of your dog, a reminder about a friends birthday, or the words youre typing into your browsers address barmust be stored somewhere. Quantum computing, a relatively new field, is still exploring where and how to store quantum information.

In a paper published recently in the journal Nature Physics, Mohammad Mirhosseini, assistant professor of electrical engineering and applied physics at the California Institute of Technology (Caltech), shows a new method his lab developed for efficiently translating electrical quantum states into sound and vice versa. This type of translation may allow for storing quantum information prepared by future quantum computers, which are likely to be made from electrical circuits.

Mohammad Mirhosseini and his team have introduced an innovative method to store quantum information by translating electrical quantum states into sound. The new technique utilizes phonons and avoids the energy loss associated with previous methods. It enables longer storage durations and represents a significant advancement in the field of quantum computing. Credit: Maayan Illustration

This method makes use of what are known as phonons, the sound equivalent of a light particle called a photon. (Remember that in quantum mechanics, all waves are particles and vice versa). The experiment investigates phonons for storing quantum information because its relatively easy to build small devices that can store these mechanical waves.

To understand how a sound wave can store information, imagine an extremely echoey room. Now, lets say you need to remember your grocery list for the afternoon, so you open the door to that room and shout, Eggs, bacon, and milk! and shut the door. An hour later, when its time to go to the grocery store, you open the door, poke your head inside, and hear your own voice still echoing, Eggs, bacon, and milk! You just used sound waves to store information.

Mohammad Mirhosseini. Credit: Caltech

Of course, in the real world, an echo like that wouldnt last very long, and your voice might end up so distorted you can no longer make out your own words, not to mention that using an entire room for storing a little bit of data would be ridiculous. The research teams solution is a tiny device consisting of flexible plates that are vibrated by sound waves at extremely high frequencies. When an electric charge is placed on those plates, they become able to interact with electrical signals carrying quantum information. This allows that information to be piped into the device for storage, and be piped out for later usenot unlike the door to the room you were shouting into earlier in this story.

According to Mohammad Mirhosseini, previous studies had investigated a special type of materials known as piezoelectrics as a means of converting mechanical energy to electrical energy in quantum applications.

These materials, however, tend to cause energy loss for electrical and sound waves, and loss is a big killer in the quantum world, Mirhosseini says. In contrast, the new method developed by Mirhosseini and his team is independent on the properties of specific materials, making it compatible with established quantum devices, which are based on microwaves.

Creating effective storage devices with small footprints has been another practical challenge for researchers working on quantum applications, says Alkim Bozkurt, a graduate student in Mirhosseinis group and the lead author of the paper.

However, our method enables the storage of quantum information from electrical circuits for durations two orders of magnitude longer than other compact mechanical devices, he adds.

Reference: A quantum electromechanical interface for long-lived phonons by Alkim Bozkurt, Han Zhao, Chaitali Joshi, Henry G. LeDuc, Peter K. Day and Mohammad Mirhosseini, 22 June 2023, Nature Physics. DOI: 10.1038/s41567-023-02080-w

Co-authors include Chaitali Joshi and Han Zhao, both postdoctoral scholars in electrical engineering and applied physics; and Peter Day and Henry LeDuc, who are scientists at the Jet Propulsion Laboratory, which Caltech manages for NASA. The research was funded in part by the KNI-Wheatley Scholars program.

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Quantum Echoes: A Revolutionary Method to Store Information as Sound Waves - SciTechDaily

For the first time, researchers have observed "quantum superchemistry" in the lab.

Long theorized but never before seen, quantum superchemistry is a phenomenon in which atoms or molecules in the same quantum state chemically react more rapidly than do atoms or molecules that are in different quantum states. A quantum state is a set of characteristics of a quantum particle, such as spin (angular momentum) or energy level.

To observe this new super-charged chemistry, researchers had to coax not just atoms, but entire molecules, into the same quantum state. When they did, however, they saw that the chemical reactions occurred collectively, rather than individually. And the more atoms were involved, meaning the greater the density of the atoms, the quicker the chemical reactions went.

"What we saw lined up with the theoretical predictions," Cheng Chin, a professor of physics at the University of Chicago who led the research, said in a statement. "This has been a scientific goal for 20 years, so it's a very exciting era."

Related: What is quantum entanglement?

"What we saw lined up with the theoretical predictions," Cheng Chin, a professor of physics at the University of Chicago who led the research, said in a statement. "This has been a scientific goal for 20 years, so it's a very exciting era."

The team reported their findings July 24 in the journal Nature Physics. They observed the quantum superchemistry in cesium atoms that paired up to form molecules. First, they cooled cesium gas to near absolute zero, the point at which all motion ceases. In this chilled state, they could ease each cesium atom into the same quantum state. They then altered the surrounding magnetic field to kick off the chemical bonding of the atoms.

These atoms reacted more quickly together to form two-atom cesium molecules than when the researchers conducted the experiment in normal, non-super-cooled gas. The resulting molecules also shared the same quantum state, at least over several milliseconds, after which the atoms and molecules start to decay, no longer oscillating together.

"[W]ith this technique, you can steer the molecules into an identical state," Chin said.

The researchers found that though the end result of the reaction was a two-atom molecule, three atoms were actually involved, with a spare atom interacting with the two bonding atoms in a way that facilitated the reaction.

This could be useful for applications in quantum chemistry and quantum computing, as molecules in the same quantum state share physical and chemical properties. The experiments are part of the field of ultracold chemistry, which aims to gain incredibly detailed control over chemical reactions by taking advantage of the quantum interactions that occur in these cold states. Ultracold particles could be used as qubits, or the quantum bits that carry information in quantum computing, for example.

The study used only simple molecules, so the next goal is to attempt to create quantum superchemistry with more complex molecules, Chin said.

"How far we can push our understanding and our knowledge of quantum engineering, into more complicated molecules, is a major research direction in this scientific community," he said.

This article was provided by Live Science.

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'Quantum superchemistry' observed for the 1st time ever - Space.com

Unraveling the mystery of insulator-to-metal transitions, new research into the quantum avalanche uncovers new insights into resistive switching and offers potential breakthroughs in microelectronics.

New Study Solves Mystery on Insulator-to-Metal Transition

A study explored insulator-to-metal transitions, uncovering discrepancies in the traditional Landau-Zener formula and offering new insights into resistive switching. By using computer simulations, the research highlights the quantum mechanics involved and suggests that electronic and thermal switching can arise simultaneously, with potential applications in microelectronics and neuromorphic computing.

Looking only at their subatomic particles, most materials can be placed into one of two categories.

Metals like copper and iron have free-flowing electrons that allow them to conduct electricity, while insulators like glass and rubber keep their electrons tightly bound and therefore do not conduct electricity.

Insulators can turn into metals when hit with an intense electric field, offering tantalizing possibilities for microelectronics and supercomputing, but the physics behind this phenomenon called resistive switching is not well understood.

Questions, like how large an electric field is needed, are fiercely debated by scientists, like University at Buffalo condensed matter theorist Jong Han.

I have been obsessed by that, he says.

Han, PhD, professor of physics in the College of Arts and Sciences, is the lead author on a study that takes a new approach to answer a long-standing mystery about insulator-to-metal transitions. The study, Correlated insulator collapse due to quantum avalanche via in-gap ladder states, was published in May in Nature Communications.

University at Buffalo physics professor Jong Han is the lead author on a new study that helps solve a longstanding physics mystery on how insulators transition into metals via an electric field, a process known as resistive switching. Credit: Douglas Levere, University at Buffalo

The difference between metals and insulators lies in quantum mechanical principles, which dictate that electrons are quantum particles and their energy levels come in bands that have forbidden gaps, Han says.

Since the 1930s, the Landau-Zener formula has served as a blueprint for determining the size of electric field needed to push an insulators electrons from its lower bands to its upper bands. But experiments in the decades since have shown materials require a much smaller electric field approximately 1,000 times smaller than the Landau-Zener formula estimated.

So, there is a huge discrepancy, and we need to have a better theory, Han says.

To solve this, Han decided to consider a different question: What happens when electrons already in the upper band of an insulator are pushed?

Han ran a computer simulation of resistive switching that accounted for the presence of electrons in the upper band. It showed that a relatively small electric field could trigger a collapse of the gap between the lower and upper bands, creating a quantum path for the electrons to go up and down between the bands.

To make an analogy, Han says, Imagine some electrons are moving on a second floor. When the floor is tilted by an electric field, electrons not only begin to move but previously forbidden quantum transitions open up and the very stability of the floor abruptly falls apart, making the electrons on different floors flow up and down.

Then, the question is no longer how the electrons on the bottom floor jump up, but the stability of higher floors under an electric field.

This idea helps solve some of the discrepancies in the Landau-Zener formula, Han says. It also provides some clarity to the debate over insulator-to-metal transitions caused by electrons themselves or those caused by extreme heat. Hans simulation suggests the quantum avalanche is not triggered by heat. However, the full insulator-to-metal transition doesnt happen until the separate temperatures of the electrons and phonons quantum vibrations of the crystals atoms equilibrate. This shows that the mechanisms for electronic and thermal switching are not exclusive of each other, Han says, but can instead arise simultaneously.

So, we have found a way to understand some corner of this whole resistive switching phenomenon, Han says. But I think its a good starting point.

The study was co-authored by Jonathan Bird, PhD, professor and chair of electrical engineering in UBs School of Engineering and Applied Sciences, who provided experimental context. His team has been studying the electrical properties of emergent nanomaterials that exhibit novel states at low temperatures, which can teach researchers a lot about the complex physics that govern electrical behavior.

While our studies are focused on resolving fundamental questions about the physics of new materials, the electrical phenomena that we reveal in these materials could ultimately provide the basis of new microelectronic technologies, such as compact memories for use in data-intensive applications like artificial intelligence, Bird says.

The research could also be crucial for areas like neuromorphic computing, which tries to emulate the electrical stimulation of the human nervous system. Our focus, however, is primarily on understanding the fundamental phenomenology, Bird says.

Since publishing the paper, Han has devised an analytic theory that matches the computers calculation well. Still, theres more for him to investigate, like the exact conditions needed for a quantum avalanche to happen.

Somebody, an experimentalist, is going to ask me, Why didnt I see that before? Han says. Some might have seen it, some might not have. We have a lot of work ahead of us to sort it out.

Reference: Correlated insulator collapse due to quantum avalanche via in-gap ladder states by Jong E. Han, Camille Aron, Xi Chen, Ishiaka Mansaray, Jae-Ho Han, Ki-Seok Kim, Michael Randle and Jonathan P. Bird, 22 May 2023, Nature Communications. DOI: 10.1038/s41467-023-38557-8

Other authors include UB physics PhD student Xi Chen; Ishiaka Mansaray, who received a PhD in physics and is now a postdoc at the National Institute of Standards and Technology; and Michael Randle, who received a PhD in electrical engineering and is now a postdoc at the Riken research institute in Japan. Other authors include international researchers representing cole Normale Suprieure, French National Centre for Scientific Research (CNRS) in Paris; Pohang University of Science and Technology; and the Center for Theoretical Physics of Complex Systems, Institute for Basic Science.

More:

Quantum Avalanche A Phenomenon That May Revolutionize Microelectronics and Supercomputing - SciTechDaily

Summer 2023 in the Northern Hemisphere is on track to be the hottest on record, and the sun is blazing in the sky. One way to deal with it is to slap on the sunscreen. But have you ever thought about how sunscreen actually works? It all comes down to how photons from the sun interact with our skin.

Photons are the messenger particles of the electromagnetic forceone of the four fundamental forces of natureand are responsible for an array of phenomena including the X-rays we use to examine broken bones, the microwaves we use to reheat food, and, probably most importantly for many people, the visible light we use to see.

During summer, we receive the maximum flux of photons from the sun due to the Earths slight tilt in its direction. At roughly the latitude of Chicago, the flux of photons is three times greater at midday in the peak of summer than during midwinter.

The sun emits photons in all parts of the electromagnetic spectrum, but the majority are from the visible, infrared and ultraviolet segments. Ultraviolet radiation plays an essential role in maintaining plant and animal life, but it has also consistently been identified as a cause of skin cancer. Understanding why is the first step to understanding how sunscreen protects us from it.

UV radiation has a higher frequency than visible or infrared light, which means that, of the three types, UV photons have the most energy. When UV photons hit your skin, their energy has to go somewhere. (Even in the summertime, no one gets a holiday from conserving energy.) In the absence of protection, this energy is transferred to the fats and proteins in your skin. The excess energy is capable of triggering mutations in our DNA, which are a cause of skin cancer.

While our bodies do possess some natural protective mechanisms against UV radiation, the prevalence of skin cancer (along with painful sunburns) clearly demonstrates that it is necessary to enhance these mechanisms artificially.

Enter sunscreen.

The active ingredients of sunscreen fall into two main categories: organic molecules and inorganic crystals. Both of these components act by absorbing UV radiation like a sponge and then dissipating it safely into the environment. How does this work? It all has to do with electrons and quantum mechanics.

As you may remember from chemistry classes, electrons in atoms and molecules occupy orbitals i.e., discrete energy levels. An electron stays put in its home orbital unless it absorbs the right amount of energy to jump up to the next one. Because of this, an electron cant contain any old amount of energyonly specific, quantized amounts. This is where the quantum comes from in quantum mechanics, which includes the study of quantized energy in subatomic particles.

The inorganic compounds in sunscreen have a crystalline structure and contain (mostly) free electrons. These electrons are constantly buzzing around and interacting, which creates a flexible orbital structure called a band gap.

The band presents a loophole to the quantized energy problem in quantum mechanics because it allows electrons to absorb a wide spectrum of energies. (After all, theres not just a single dangerous wavelength of light from the sun.)

In isolated atoms, you have pretty sharp, quantized transitions between atomic orbitals, says Thomas Wolf, a physical chemist at the US Department of Energys SLAC National Accelerator Laboratory. If you now have many atoms in a lattice like in an inorganic sunscreen, their atomic orbitals can overlap. This leads to many quantized transitions, which are fairly similar in energy and form bands. If light gets absorbed, electrons get promoted from an occupied to an unoccupied band across a band gap.

When UV photons from the sun hit inorganic sunscreen, the electrons dash from the lower orbitals into the excited orbitals, each jumping a distance equivalent to the energy of the photon that excited it. After a while, the excited electrons drop back down to their original orbitals, releasing the energy they absorbed as heat.

Organic sunscreens work in a similar way, but their active ingredients have no band gaps. Instead, they use the beauty of covalent bonds and hybridized orbitals.

Covalent bonds form when an electron is shared almost evenly between two atoms, and this creates orbital hybridization (the mixing and merging of two independent atomic orbitals into a new super orbital, so to speak). Organic sunscreens use rings and chains of covalently bonded carbon atoms to play with the distance between these new ground and excited states. Combining many different molecules with many different orbital configurations allows organic sunscreens to protect the skin against many different wavelengths of light.

There is ongoing research to find the most efficient mechanism for the excited electrons in sunscreen to release their energy, with researchers taking inspiration from the mechanisms that plants use to protect themselves from the sun. Scientists are also researching how to make organic sunscreens hardier, since over time and after atoms have absorbed a certain amount of energy, the bonds between them can snap.

So there you have it, the science behind sunscreen. To all you physics students out there: Even on the beach, you are still applying quantum mechanics, literally to your skin!

Originally posted here:

Applications of quantum mechanics at the beach - Symmetry magazine

This book is for readers with an interest in physics and astronomy. While some concepts are difficult, no knowledge of physics or mathematics is needed.

On the Origin of Time Stephen Hawkings Final Theory

Thomas Hertog, Bantam New York, 313 pages

This is not a book for a leisurely afternoon read in the car while waiting to pick up the kids after hockey practice. It needs concentration and a willingness to reread some passages, dealing as it does to a large extent with aspects of quantum physics, which by itself often requires a suspension of disbelief.

Not a very enthusiastic opening statement for a book review you may think, but readers who persevere will be more than richly rewarded with insights into some of the most exciting concepts in modern cosmology.

The author was for a long time a collaborator and friend of Stephen Hawking, who certainly needs no introduction. His admiration for his late colleague shines from almost every page.

Together they spent years theorizing about the universes biophilic nature (a word Hertog clearly likes), that is to say, why is our cosmos so apparently fine-tuned for life. Change just one or two of many physical constants by miniscule amounts and we wont be here to discuss this phenomenon.

Why is this so? Hawking and Hertog werent the first to examine this and wont be the last. This book describes their thoughts in fascinating and almost overwhelming detail.

Various theories have been proposed to explain this, some gaining general acceptance, others seemingly outlandish even when finding favour in the physics community. After all, when a theory states that every time something happens the universe splits into consecutively multiplying and different multiverses, not in contact with each other, some where the observer adds sugar to coffee and some adding salt, or adding nothing at all (or a gazillion other possibilities), it may be hard to take seriously.

The thing is: the two-split experiment (see link at the end), which is fundamental to quantum theory and which has been proved multiple times, is one of the strangest concepts I know, but the phenomenon it illustrates is real so what must one make of these strange theories which also involve quantum physics?

Hertog starts his walk through the cosmos with the big bang and the Belgian astronomer-priest Georges Lematre, explaining Hawkings no-boundary theory of time folding into space, ceasing to exist at the very beginning of the universe. We are then told about the quantum soup of particles which emerged, ending with the realization that the laws of physics as we know them today probably emerged right at the beginning, having been subject to what one may perhaps call natural selection in the style of Darwin.

Hawking has disowned his bestselling Brief History of Time of some years ago, and together with Hertog devised what he calls top-down cosmology. This viewpoint holds (inter alia) that the nature and course of development of the universe is influenced by observers, which are often and incorrectly stated by some journalists to be humans. This need not be the case, a casual glance by a mouse will suffice, or an electron hitting a crystal.

This state of affairs is (for me) somewhat reminiscent of the anthropic principle, although Hertog never mentions it.

We end with the realization that the universe may be a hologram: At a conceptual level, holography seals the top-down approach to cosmology. The central tenet of holographic cosmology that the past projects from a web of entangled quantum particles that form a lower-dimensional hologram implies a top-down view of the universe. Holography tells us that there is an entity more basic than time a hologram from which the past emerges.

Whatever ones opinion of the Hawking-Hertog universe may be, I find one aspect deeply satisfying: previously cosmologists looked at the universe as if from the outside in. Hawking and Hertogs perspective is from the inside we are part of the universe, not separate from it.

This book is for readers with an interest in physics and astronomy. While some concepts are difficult, no knowledge of physics or mathematics is needed.

Anyone who wants to find out more about the double slit experiment can watch this video: https://www.youtube.com/watch?v=A9tKncAdlHQ.

The views and opinions expressed in this article are those of the author, and do not necessarily reflect the position of this publication.

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Book Review: On the Origin of Time Stephen Hawking's Final Theory - Moose Jaw Today