Quantum interrogation of imperfect absorbers using post-selection

Muhammad Abdullah Ijaz; Syed Bilal Hyder Shah; Muhammad Sabieh Anwar

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arXiv · 2407.01735

Quantum interrogation of imperfect absorbers using post-selection

Muhammad Abdullah Ijaz·Syed Bilal Hyder Shah·Muhammad Sabieh Anwar

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Abstract

We propose a scheme for quantum interrogation measurements using constructive interference and post-selection to achieve single-pass high-efficiency detection for imperfect absorbers. We illustrate that our method works for heralded single-photon and weak attenuated sources. We also study the influence of noise in our experimental implementation and show that post-selection imparts additional robustness to the scheme against noise. We further demonstrate that fringe visibility from post-selection interferometry can be used to quantify the transmittance of the imperfect absorber. An interesting link between the interrogation and weak values of nonunitary operators is also highlighted.

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Muhammad Abdullah Ijaz, Syed Bilal Hyder Shah, Muhammad Sabieh Anwar. 2024-07-01. Quantum interrogation of imperfect absorbers using post-selection. https://arxiv.org/abs/2407.01735

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