Researchers have discovered a hard-to-observe type of spin in a quantum mechanical system. In physics, a quantum mechanical system is a set of components that interact at the quantum scale. This is the realm of atoms and subatomic particles such as those defined in the Standard Model of Particle Physics. Spins are magnetic particles in a quantum system. The researchers successfully simulated and measured how spins can exhibit a type of motion known as Kardar-Parisi-Zhang (KPZ) in solid materials at various temperatures. Their findings demonstrate that KPZ motion accurately describes the changes in time of spin chains—linear channels of spins that interact with one another—in certain quantum materials.

Long wavelength spin fluctuations in a quantum spin chain correspond to superdiffusive classical hydrodynamics belonging to the Kardar-Parisi-Zhang (KPZ) universality class.

Some three decades ago, Alan Tennant was working toward a bachelor’s degree in physics in Scotland and Cristian Batista was doing the same in Argentina. They had never met, but their paths would merge years later through a shared interest in the structure and dynamics of quantum materials. It’s a common story in science, this bringing together people from the world over, but the Shull Wollan Center has emerged as a rich and unique chapter, connecting scientists from different specialties, generations, and institutions and placing within their reach some of the world’s most sophisticated facilities. As such, it has become an incubator for driving the creative thinking and innovation needed to thrive both in a quantum economy and in the education of next-generation scientists.

Using complementary computing calculations and neutron scattering techniques, researchers from the Department of Energy’s Oak Ridge and Lawrence Berkeley national laboratories and the University of California, Berkeley, discovered the existence of an elusive type of spin dynamics in a quantum mechanical system.

Scientists seek to use quantum materials—those that have correlated order at the subatomic level—for electronic devices, quantum computers, and superconductors. Quantum materials owe many of their properties to the physics that is occurring on the smallest scales, physics that is fully quantum mechanical.