Wave-packet Dynamics in Synthetic Non-Abelian Gauge Fields

TL;DR

This paper investigates the dynamics of wave packets in a degenerated fermionic atomic gas under a synthetic non-Abelian SU(2) gauge field, revealing noninertial motion, spin Hall effects, and connections to relativistic Zitterbewegung.

Contribution

It demonstrates the noninertial wave packet dynamics induced by a synthetic non-Abelian gauge field and analyzes its spin-dependent anisotropic behavior and relation to Zitterbewegung.

Findings

Observation of spin Hall effect in wave packet dynamics

Identification of anisotropic amplitude and frequency due to spin texture

Comparison of wave packet motion with Zitterbewegung phenomenon

Abstract

It is generally admitted that in quantum mechanics, the electromagnetic potentials have physical interpretations otherwise absent in classical physics as illustrated by the Aharonov-Bohm effect. In 1984, Berry interpreted this effect as a geometrical phase factor. The same year, Wilczek and Zee generalized the concept of Berry phases to degenerate levels and showed that a non-Abelian gauge field arises in these systems. In sharp contrast with the Abelian case, spatially uniform non-Abelian gauge fields can induce particle noninertial motion. We explore this intriguing phenomenon with a degenerated Fermionic atomic gas subject to a two-dimensional synthetic SU(2) non-Abelian gauge field. We reveal the spin Hall nature of the noninertial dynamic as well as its anisotropy in amplitude and frequency due to the spin texture of the system. We finally draw the similarities and differences of the observed wave packet dynamic and the celebrated Zitterbewegung effect of the relativistic Dirac equation.