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arXiv · 2007.05444

The Heisenberg picture of photodetection

Saumya Biswas·S. J. van Enk
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Abstract

We construct a class of Hamiltonians that describe the photodetection process from beginning to end. Our Hamiltonians describe the creation of a photon, how the photon travels to an absorber (such as a molecule), how the molecule absorbs the photon, and how the molecule after irreversibly changing its configuration triggers an amplification process---at a wavelength that may be very different from the photon's wavelength---thus producing a macroscopic signal. We use a simple prototype Hamiltonian to describe the single-photon detection process analytically in the Heisenberg picture, which neatly separates desirable from undesirable effects. Extensions to more complicated Hamiltonians are pointed out.

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Saumya Biswas, S. J. van Enk. 2020-07-10. The Heisenberg picture of photodetection. https://doi.org/10.1103/physreva.102.033705

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