Saarikoski Henri, Baltanás José Pablo, Vázquez-Lozano J Enrique, Nitta Junsaku, Frustaglia Diego
RIKEN Center for Emergent Matter Science (CEMS), Saitama 351-0198, Japan.
J Phys Condens Matter. 2016 Apr 27;28(16):166002. doi: 10.1088/0953-8984/28/16/166002. Epub 2016 Mar 24.
We address the development of geometric phases in classical and quantum magnetic moments (spin-1/2) precessing in an external magnetic field. We show that nonadiabatic dynamics lead to a topological phase transition determined by a change in the driving field topology. The transition is associated with an effective geometric phase which is identified from the paths of the magnetic moments in a spherical geometry. The topological transition presents close similarities between SO(3) and SU(2) cases but features differences in, e.g. the adiabatic limits of the geometric phases, being 2π and π in the classical and the quantum case, respectively. We discuss possible experiments where the effective geometric phase would be observable.
