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Physical Review A

Quantum spectroscopy with biphotons: Lyapunov-based input-output dynamics

Sameer Dambal, Ajay Ram Srimath Kandada, Eric R. Bittner

Published Nov 17, 2025• 4 citations
Publisher

Abstract

We develop a Lyapunov-based framework to model the evolution of entangled biphotons interacting with cavity and material modes. Using Gaussian-preserving dynamics and M\o{}ller operators, we map input joint spectral amplitudes to experimentally measurable joint spectral intensities. Our model reproduces key features of observed spectra and reveals off-diagonal correlations arising from cavity decay, providing a scalable and tractable tool for quantum spectroscopic analysis.

DOI
10.1103/wgnx-l7qx

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