Communications in Theoretical Physics
Nonadiabatic Berry Phase of a Two-State System and Nonstationarity of Quantum States
Yian Lei, J. Y. Zeng
Abstract
The nonadiabatic Berry phases in the magnetic resonance under various initial conditions are investigated and compared with the adiabatic Berry phase. The general formalism for calculating the nonadiabatic Berry phase of a two-state system in terms of the expansion of instantaneous energy eigenstates is presented. Some numerical calculations and discussions are made. The Berry phase of a two-statesystem under an impulsive interaction is addressed.