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arXiv · 2502.18707

Purified pseudomode model for nonlinear system-bath interactions

Cheng Zhang·Neill Lambert·Xin-Qi Li·Mauro Cirio·Pengfei Liang
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Abstract

The theory of purified pseudomodes [arXiv:2412.04264 (2024)] was recently developed to provide a numerical tool for the analysis of the properties of a quantum system and the environment it couples to via linear system-bath interactions. Here we extend this theory to allow for the description of general nonlinear system-bath interactions. We demonstrate the validity of our method by considering the spontaneous decay of a two-level atom placed inside a single-mode lossy cavity and furthermore, its potential application to nanophotonics by calculating the resonance fluorescence spectrum of a quantum dot in the presence of a phonon environment. Our method provides a useful tool for the study of phonon-assisted emission in quantum dots and holds the the promise for broad applications in fields like quantum biology, nonlinear phononics, and nanophotonics.

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Cheng Zhang, Neill Lambert, Xin-Qi Li, Mauro Cirio, Pengfei Liang. 2025-02-25. Purified pseudomode model for nonlinear system-bath interactions. https://doi.org/10.1103/c91x-bhqw

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