Branch points in the complex plane and geometric phases.
Branch points in the complex plane and geometric phases.
复制标题
复平面和几何相中的分支点。
DOI:
10.1103/physreve.65.026217
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发表时间:
2002
期刊:
影响因子:
--
通讯作者:
I. Rotter
中科院分区:
文献类型:
--
作者:
I. Rotter
Laser-induced degenerate states (LIDS) are equivalent to double poles of the S matrix that are branch points in the complex plane (BPCP). These branch points cause geometric phase changes by encircling them adiabatically around a closed circuit by varying certain parameters. They cause also the well-known phase changes appearing by encircling a diabolic point (DP) being a singularity associated with level repulsion. In both cases, the wave functions are exchanged, Phi(i) --> +/- iPhi(j not equal i), at the critical value of the parameter where the states avoid crossing. Such a critical point is passed twice by encircling a DP but only once by surrounding a BPCP. As a consequence, the phase changes are different in both cases. A second surrounding restores the wave functions including their phases in both cases (when the BPCP is well isolated from others and the time of encircling is shorter than the lifetime of the two states). The different interference pictures appearing in surrounding LIDS adiabatically in opposite directions on a closed circuit represent a completion of the work by Berry.