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A solid is made of atoms that are, more or less, locked in an ordered structure. A liquid, on the other hand, is made of atoms that can flow freely around and past each other. But imagine atoms that stay unfrozen, like those in a liquidbut which are in a constantly changing magnetic mess.

What you have then is a never-before-seen state of matter, a state of quantum weirdness called a quantum spin liquid. Now, by carefully manipulating atoms, researchers have managed to create this state in the laboratory. The researchers published their work in the journal Science on December 2.

Scientists had discussed theories about spin liquids for years. But we really got very interested in this when these theorists, here at Harvard, finally found a way to actually generate the quantum spin liquids, says Giulia Semeghini, a physicist and postdoc at Harvard University, who coordinated the research project and was one of the paper authors.

Under extreme conditions not typically found on Earth, the rules of quantum mechanics can twist atoms into all sorts of exotica. Take, for instance, degenerate matter, found in the hearts of dead stars like white dwarfs or neutron stars, where extreme pressures cook atoms into slurries of subatomic particles. Or, for another, the Bose-Einstein condensate, in which multiple atoms at very low temperatures sort of merge together to act as one (its creation won the 2001 Nobel Prize in Physics).

The quantum spin liquid is the latest entry in that bestiary of cryptid states. Its atoms dont freeze into any sort of ordered state, and theyre constantly in flux.

[Related: IBMs latest quantum chip breaks the elusive 100-qubit barrier]

The spin in the name refers to a property inherent to each particleeither up or downwhich gives rise to magnetic fields. In a normal magnet, all the spins point up or down in a careful order. In a quantum spin liquid, on the other hand, theres a third spin in the picture. This prevents coherent magnetic fields from forming.

This, combined with the esoteric rules of quantum mechanics, means that the spins are constantly in different positions at once. If you look at just a few particles, its hard to tell whether you have a quantum liquid or, if you do, what properties it has.

Quantum spin liquids were first theorized in 1973 by a physicist named Philip W. Anderson, and physicists have been trying to get their hands on this matter ever since. Many different experimentstried to create and observe this type of state. But this has actually turned out to be very challenging, says Mikhail Lukin, a physicist at Harvard University and one of the paper authors.

The researchers at Harvard had a new tool in their arsenal: what they call a programmable quantum simulator. Essentially, its a machine that allows them to play with individual atoms. Using specifically focused laser beams, researchers can shuffle atoms around a two-dimensional grid like magnets on a whiteboard.

We can control the position of each atom individually, says Semeghini. We can position them individually in any shape or form that we want.

Moreover, to actually determine if they had successfully created a quantum spin liquid, the researchers took advantage of something called quantum entanglement. They energized the atoms, which began to interact: changes in the property of one atom would reflect in another. By looking at those connections, the scientists found the confirmation they needed.

All this might seem like creating abstract matter for abstract matters sakebut thats part of the appeal. We can kind of touch it, poke, play with it, even in some ways talk to this state, manipulate it, and make it do what we want, says Lukin. Thats whats really exciting.

But scientists do think quantum spin liquids have valuable applications, too. Just venture into the realms of quantum computers.

Quantum computers have the potential to far outstrip their traditional counterparts. Compared with computers today, quantum computers could create better simulations of systems such as molecules and far more quickly complete certain calculations.

But what scientists use as the building blocks of quantum computers can leave something to be desired. Those blocks, called qubits, are often things like individual particles or atomic nucleiwhich are sensitive to the slightest bit of noise or temperature fluctuations. Quantum spin liquids, with information stored in how theyre arranged, could be less finicky qubits.

If researchers were able to demonstrate that a quantum spin liquid could be used as a qubit, says Semeghini, it could lead to an entirely new sort of quantum computer.

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Quantum physicists have created a never-before-seen state of matter - Popular Science

Robert Crease, professor and chair of the Department of Philosophy in the College of Arts and Sciences, has been awarded the 2021 Institute of Physics (IOP) William Thomson, Lord Kelvin Medal and Prize. Crease has received this award for his 21 years writing Physics Worlds outstanding Critical Point column, devoted to describing key humanities concepts for scientists, and explaining the significance of key scientific ideas for humanists.

Crease has written, co-written, translated, and edited nearly 20 books on the history and philosophy of science, several of which sprang from material in Critical Point. These books have been reviewed in places as diverse as The Economist, the London Review of Books, and the Wall Street Journal, and translated into a total of 10 languages. One book in particular, The Quantum Moment: How Planck, Bohr, Einstein, and Heisenberg Taught Us to Love Uncertainty, is about the real and fanciful impact that quantum mechanics has had on philosophy, culture, and life. The book stemmed from an innovative class that Crease and physicist Alfred Goldhaber co-taught at Stony Brook University.

My sincere congratulations to Bob on his receipt of the William Thomson, Lord Kelvin Medal and Prize, said Nicole Sampson, dean of the College of Arts and Sciences and distinguished professor of chemistry. His decades-long contribution to the sciences from a humanists perspective, through his Critical Point column and numerous publications as well as inventive course offerings that blend the arts and sciences, is testament to the importance of interdisciplinary collaboration as we navigate our ever-changing world. I applaud Bob for his commitment to communicating ideas and knowledge from his own area of expertise for the benefit of other disciplines.

Crease is also co-editor-in-chief of Physics in Perspective, whose mission is to bridge the gulf between physicists and non-physicists through historical and philosophical studies that typically display the unpredictable as well as the cross-disciplinary interplay of observation, experiment, and theory that has occurred over extended periods of time in academic, governmental, and industrial settings and in allied disciplines such as astrophysics, chemical physics, and geophysics.

Im thrilled to get this award, said Crease. The IOP, a century-old scientific organization, gave it to me for more than 20 years of writing the column, Critical Point for Physics World. Its a good sign for the humanities, for the column explores the numerous intersections between humanities and the sciences. In a science-dominated world, I think, the vitality of the humanities is threatened, not by interacting too much with the sciences, but too little. By the way, Kelvin, the scientist for whom the award is named, occupied what at the time was called a Chair of Natural Philosophy.

Other books include Philosophy of Physics, an IOP ebook, and the final portion of J. Robert Oppenheimer: A Life, which was begun by physicist Abraham Pais and left incomplete with his death. Crease also edited Science Policy Up Close by physicist and U.S. Presidential Science Advisor John H. Marburger III. For these and other contributions to history and philosophy of science, Crease was elected a fellow of the APS and IOP.

Crease received BA from Amherst College and PhD from Columbia University. He has written more than 75 reviews, editorials, and other short pieces on philosophy, history, and science for academic journals and The New York Times, Wall Street Journal, Nature, Newsday, and more. Crease has also appeared on a range of radio programs, from the BBC to the offbeat Talk Nerdy.

On behalf of the Institute of Physics, I warmly congratulate all of this years Award winners, said Professor Sheila Rowan, president of the Institute of Physics. Each and every one of them has made a significant and positive impact in their profession, whether as a researcher, teacher, industrialist, technician or apprentice. Recent events have underlined the absolute necessity to encourage and reward our scientists and those who teach and encourage future generations. We rely on their dedication and innovation to improve many aspects of the lives of individuals and of our wider society.

The Institute of Physics is the professional body and learned society for physics, and the leading body for practising physicists, in the UK and Ireland. The IOP awards celebrate physicists at every stage of their career; from those just starting out through to physicists at the peak of their careers, and those with a distinguished career behind them.They also recognize and celebrate companies which are successful in the application of physics and innovation, as well as employers who demonstrate their commitment and contribution to scientific and engineering apprenticeship schemes.

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Robert Crease Awarded 2021 Institute of Physics William Thomson, Lord Kelvin Medal and Prize | | SBU News - Stony Brook News