The Photodetection Process under the Conditions of an Imperfect Measurement Device

TL;DR

This paper develops a formalism for modeling photodetection with imperfect devices using POVMs, enabling improved quantum state reconstruction of cavity modes despite measurement imperfections.

Contribution

It introduces a set of nonorthogonal POVMs and superoperators for modeling nonideal photodetection, advancing quantum measurement theory.

Findings

Derived Kraus representations for conditional evolution

Recalculated detection probabilities for mixed states

Enhanced quantum state reconstruction methods

Abstract

The process of cavity mode quantum state photodetection subject to a nonideal measurement device is under consideration. A set of nonorthogonal probabilistic operator valued measures (POVMs) describing the photodetection process is suggested. The superoperators of conditional system evolution and their Kraus representations are obtained. Developed formalism is used to the quantum state reconstruction problem. We recalculate the probabilities of hypotheses about the initial state of cavity quantum mode in the case of unknown superposition of vacuum and single photon states.