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arXiv · 2206.00933

Superbunching in cathodoluminescence: a master equation approach

Tatsuro Yuge·Naoki Yamamoto·Takumi Sannomiya·Keiichirou Akiba
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Abstract

We propose a theoretical model of a master equation for cathodoluminescence (CL). The master equation describes simultaneous excitation of multiple emitters by an incoming electron and radiative decay of individual emitters. We investigate the normalized second-order correlation function, $g^{(2)}(τ)$, of this model. We derive the exact formula for the zero-time delay correlation, $g^{(2)}(0)$, and show that the model successfully describes giant bunching (superbunching) in the CL. We also derive an approximate form of $g^{(2)}(τ)$, which is valid for small excitation rate. Furthermore, we discuss the state of the radiation field of the CL. We reveal that the superbunching results from a mixture of an excited photon state and the vacuum state and that this type of state is realized in the CL.

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Tatsuro Yuge, Naoki Yamamoto, Takumi Sannomiya, Keiichirou Akiba. 2023-04-10. Superbunching in cathodoluminescence: a master equation approach. https://doi.org/10.1103/physrevb.107.165303

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