Nanowerk February 28, 2022
The boomerang effect is a disorder-induced behavior which inhibits transport of electrons turning what would otherwise be a conducting material into an insulator. An international team of researchers (USA – UC Santa Barbara, Brazil, France) reported experimental observation and characterization of this surprising quantum-mechanical phenomenon. They exposed a gas of ultracold lithium atoms to a phase-shifted pair of optical lattices to realize a “quantum kicked rotor,” a momentum-space realization of Anderson-localized matter. They observed the characteristic departure from and return to the origin that is the key signature of the boomerang effect. Detailed characterization revealed the key dependence of the boomerang effect on time-reversal symmetry and localization: The disruption of either of these conditions destroys the boomerang dynamics. The experiments validated a powerful dynamical probe of the uniquely quantum-mechanical nature of the localized state, applicable to a general class of disordered systems. The results suggest a variety of intriguing topics for future exploration, including tunable boomerang phenomena in higher-dimensional and interacting systems and implications for ultrafast electron dynamics in disordered solids…read more. Open Access TECHNICAL ARTICLE
Observation of quantum boomerang effect…Credit: Phys. Rev. X 12, 011035, 23 February 2022