arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2104.06227quant-ph
收藏

Berry相位的弱测量

Weak Measurement of Berry's Phase

Z. Gedik

摘要:

量子测量可以推广到包括复数量。投影算符的量子弱值可以与三阶Bargmann不变量联系起来。弱值的幅角变成,直到一个符号,等于与三个状态向量相关联的Berry相位。在对称信息完备正算子值测度(SIC-POVM)的情况下,这种关系具有特别简单的形式。利用强弱交替测量可以直接确定Berry相位,这说明Berry相位的实部和虚部以及弱值的模和辐角都具有物理意义。对于任意的投影算子,当投影算子、预选择态和后选择态位于一条所谓的零相位曲线上时,弱值是实的,其中包含这三个态的测地线是一种特殊情况。

英文摘要:

Quantum measurements can be generalized to include complex quantities. It is possible to relate the quantum weak values of projection operators to the third order Bargmann invariants. The argument of the weak value becomes, up to a sign, equal to the Berry's phase associated with the three state vectors. In case of symmetric informationally complete, positive operator valued measures (SIC-POVMs), this relation takes a particularly simple form. Alternating strong and weak measurements can be used to determine Berry's phase directly, which demonstrates that not only their real and imaginary parts but also moduli and arguments of weak values have a physical significance. For an arbitrary projection operator, weak value is real when the projector, pre- and post-selected states lie on a so-called null phase curve which includes the geodesic containing the three states as a special case.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑