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arXiv · 2603.27160

Nonclassical Photon-Bundle Correlations in Quantum Rabi Models

Abstract

We investigate nonclassical photon-bundle correlations in the quantum Rabi model and its extended cases, using the quantum dressed master equation. By tuning the light--matter coupling strength at finite temperature, the quantum Rabi model exhibits controllable nonclassical transitions between two-photon bundle bunching and antibunching, allowing for the two-photon bundle emission and statistics. We further introduce anisotropic coupling and nonlinear Stark interactions, which enrich the photon statistical behaviors and provide additional tunability of photon-bundle correlations. Extreme correlation behaviors are found to be closely linked to excited-state quantum phase transitions, suggesting a potential pathway for predicting and exploiting excited-state phenomena. These effects can be controlled solely by tuning intrinsic system parameters, without the need for an external modulating field. The quantum Rabi model family thus provides a flexible and experimentally feasible platform for high-purity photon bundle generation and controllable multi-photon sources.

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BibTeXRIS

Yong-Xin Zhang, Chen Wang, Qing-Hu Chen. 2026-03-28. Nonclassical Photon-Bundle Correlations in Quantum Rabi Models. https://doi.org/10.1364/oe.596808

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