Zapping quantum materials with lasers tells us how atoms relate

Phase transitions are a fundamental piece of physics and chemistry. We’re all familiar with different phases of water, for example, but this idea of a system of particles changing what it looks like and how it behaves is really ubiquitous in science. And while we know the outcome of water changing into ice, the precise process leads to many different kinds…

Phasing quantum annealers into experiments from nonequilibrium physics

It is established that matter can transition between different phases when certain parameters, such as temperature, are changed. Although phase transitions are common (like water turning into ice in a freezer), the dynamics that govern these processes are highly complex and constitute a prominent problem in the field of nonequilibrium physics. …

Researchers perform quantum simulation of dynamical phase transitions

Quantum simulation uses a controllable quantum system to mimic complex systems or solve intractable problems, among which the non-equilibrium problems of quantum many-body systems have attracted wide research interest. Such systems are hard to simulate using classical computers. Instead, popular quantum simulators, such as superconducting circuits, can provide insights into these problems. As considerable advances have been made in scalability, coherence…

Machine learning puts a new spin on spin models

Researchers from Tokyo Metropolitan University have used machine learning to analyze spin models, which are used in physics to study phase transitions. Previous work showed that an image/handwriting classification model could be applied to distinguish states in the simplest models. The team showed the approach is applicable to more complex models and found that an AI trained on one model and…

Ultracold gases in time-dependent magnetic fields

It is now technically possible to hold groups of atoms at temperatures that are only a few hundredths of a degree above absolute zero. This so-called ‘ultracold gas’ loaded in an optical lattice is an extremely powerful platform to study quantum mechanical phenomena including phase transitions, due to the excellent control of experimental parameters, such as potential depths, inter-particle interaction strengths…

Quantum transition makes electrons behave as if they lack spin

The common phase transitions are those that occur as a function of temperature variation. Ice changes phase to become liquid water at 0 degrees Celsius. Liquid water changes phase to become water vapor at 100 degrees Celsius. Similarly, magnetic materials become nonmagnetic at critical temperatures. However, there are also phase transitions that do not depend on temperature. They occur in the…