Physicists Now Understand Why a Weird Quantum Gas Refuses to Heat Up

Typically, adding energy to a system makes it hotter. But last year, scientists demonstrated that quantum systems don’t always follow those patterns, finding a quantum gas that essentially refuses to heat up. After some investigating, a closely related team identified the microscopic origin of this seemingly nonsensical behavior, reporting its findings in a recent paper published in Physical Review Letters. For the study, the researchers, an international team based in China and Austria, devised a mathematical framework that allowed them to track the individual interactions within the system. As a result, they discovered that in this particular structure, strongly interacting atoms reshape how the system behaves within the local lattices. Key to this finding is a phenomenon called dynamical localization, or an “unexpected halt in energy growth” for single particles exposed to periodic “kicks” of energy in quantum systems, according to the paper. That “starkly contrasts our everyday experience, which tells us that driven systems generally thermalize to infinite temperatures,” the study noted. Physicists wondered if similar behavior could be observed in more complex systems, since si