Time-dependent gauge transformations and Berry's phase

✍ Scribed by Jiu-Qing Liang; H.J.W Müller-Kirsten

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 625 KB
• Volume: 219
• Category: Article
• ISSN: 0003-4916
• DOI: 10.1016/0003-4916(92)90311-9

✦ Synopsis

The time-dependent gauge transformation is discussed in the context of modified Lagrangian and Hamiltonian formalisms in which time is treated as a dynamical coordinate. It is shown that Berry's phase is invariant under both time-dependent unitary and generalized gauge transformations. The Berry phase is therefore unique. It is then demonstrated that the Berry phase can be shifted into the-dynamical part of the total phase by choosing a new set of instantaneous eigenstates which are associated with a different gauge. This procedure breaks the gauge equivalence and also changes the dynamics of the system considered.