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Updated: Jun 11, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
A unified description of sum frequency generation, parametric down conversion and two-photon fluorescence
Oleksiy Roslyak1, Shaul Mukamel
1Chemistry Department, University of California, Irvine, CA 92697-2025, USA.
Molecular Physics
|July 8, 2010
Summary
This study introduces a new method to calculate nonlinear optical processes. It accounts for both system responses and natural fluctuations, enabling precise modeling of light-matter interactions.
Area of Science:
- Quantum Optics
- Nonlinear Optics
- Theoretical Physics
Background:
- Nonlinear optical processes are crucial in many scientific fields.
- Existing methods often struggle to accurately model both system response and spontaneous fluctuations.
- A unified theoretical framework is needed for comprehensive analysis.
Purpose of the Study:
- To develop a superoperator non-equilibrium Green's function formalism.
- To compute nonlinear optical processes involving classical and quantum optical modes.
- To differentiate between coherent and incoherent light-matter interactions.
Main Methods:
- Derivation of closed correlation-function expressions using superoperator time-ordering.
- Inclusion of both causal response and non-causal spontaneous fluctuations.
- Application to coherent three-wave mixing processes.
Main Results:
- The formalism successfully computes nonlinear optical processes.
- It accounts for the interplay between system response and spontaneous fluctuations.
- Comparison of coherent processes (e.g., sum frequency generation) with incoherent counterparts (e.g., two-photon fluorescence).
Conclusions:
- The presented formalism provides a robust tool for studying nonlinear optics.
- It enables accurate modeling of complex light-matter interactions.
- This work advances the understanding of coherent versus incoherent optical phenomena.
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