Nonlinear quantum interferometric spectroscopy with entangled photon pairs

TL;DR

This paper presents a theoretical framework for nonlinear quantum interferometric spectroscopy using entangled photon pairs, accounting for relaxation, dephasing, and complex light-matter interactions, with insights into controlling observed phenomena.

Contribution

It introduces a modular, Liouville-space-based approach to analyze entangled photon interferometric spectroscopy, simplifying interpretation and highlighting the role of entanglement and time variables.

Findings

Derived closed-form expressions for time-resolved photon counting signals.

Identified how entanglement and interferometric timescales influence observed physics.

Showed that certain processes dominate in the limit of small entanglement times.

Abstract

We develop closed expressions for a time-resolved photon counting signal induced by an entangled photon pair in an interferometric spectroscopy setup. Superoperator expressions in Liouville-space are derived that can account for relaxation and dephasing induced by coupling to a bath. Interferometric setups mix matter and light variables non-trivially, which complicates their interpretation. We provide an intuitive modular framework for this setup that simplifies its description. Based on separation between the detection stage and the light-matter interaction processes. We show that the pair entanglement time and the interferometric time-variables control the observed physics time-scale. Only a few processes contribute in the limiting case of small entanglement time with respect to the sample response, and specific contributions can be singled out.