Field-driven geometrical phases in a time-periodic quantum system
We apply Floquet theory to explore the geometry of the Hilbert space under the influence of a time-periodic field. The geometrical phase is found to be induced by field-driven hybridizations when the photon energy of the driving field is close to the transition energies of the states of a quantum system. The phases of two hybridized states are phase locked to each other. We show that the geometric