Mixed State Geometric Phases, Entangled Systems, and Local Unitary Transformations
Mixed State Geometric Phases, Entangled Systems, and Local Unitary Transformations
The geometric phase for a pure quantal state undergoing an arbitrary evolution is a "memory" of the geometry of the path in the projective Hilbert space of the system. We find that Uhlmann's geometric phase for a mixed quantal state undergoing unitary evolution depends not only on the geometry of …