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arXiv · 2103.13100

Accuracy of the quantum regression theorem for photon emission from a quantum dot

M. Cosacchi·T. Seidelmann·M. Cygorek·A. Vagov·D. E. Reiter·V. M. Axt
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Abstract

The quantum regression theorem (QRT) is the most-widely used tool for calculating multitime correlation functions for the assessment of quantum emitters. It is an approximate method based on a Markov assumption for the environmental coupling. In this work we quantify properties of photons emitted from a single quantum dot coupled to phonons. For the single-photon purity and the indistinguishability, we compare numerically exact path-integral results with those obtained from the QRT. It is demonstrated that the QRT systematically overestimates the influence of the environment for typical quantum dots used in quantum information technology.

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M. Cosacchi, T. Seidelmann, M. Cygorek, A. Vagov, D. E. Reiter, V. M. Axt. 2021-03-24. Accuracy of the quantum regression theorem for photon emission from a quantum dot. https://doi.org/10.1103/physrevlett.127.100402

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