Detection of Berry’s Phase in a Bulk Rashba Semiconductor

Abstract

Spin Berry's Phase When a quantum mechanical system performs an adiabatic cyclic path in the space of the parameters that affect its state (such as, for example, the magnetic field) its wave function may acquire an additional phase rather than go back to its original value. This quantity, called the Berry's phase, is associated with the topological properties of the parameter space and has been observed in materials such as graphene and bismuth. Murakawa et al. (p. 1490 ) observe a Berry's phase equal to π in the material BiTeI in which the phenomenon is predicted to be a consequence of a very strong coupling of spin and orbital degrees of freedom realized through the so-called Rashba effect.