Modular-value-based metrology with spin coherent pointers

Publication date: Available online 29 October 2018Source: Physics Letters AAuthor(s): Le Bin Ho, Yasushi KondoAbstractWe discuss an optimal modular-value-based measurement with a spin coherent pointer: A quantum system is exposed to a field whose strength is to be estimated through its modular value. We evaluate the quantum Fisher information as a figure of merit. We found that the modular-value-based measurement can reach the same ultimate precision limit of the estimation as those of measurements without postselections. The quantum Fisher information can be increased when the dimension of the pointer state increases. We also consider the pointer under a phase-flip error. Our study should motivate researchers to apply the modular-value-based measurements for quantum metrology.

Source: Physics Letters A - October 30, 2018 Category: Physics Source Type: research