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Updated: May 13, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Cavity quantum electrodynamics ring coupled cluster and the random phase approximation
A Eugene DePrince1, Stephen H Yuwono1, Henk Eshuis2
1Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, USA.
The Journal of Chemical Physics
|May 12, 2026
Summary
The study shows that Random Phase Approximation (RPA) and Coupled Cluster Doubles (CCD) models yield equivalent ground-state correlation energy in cavity Quantum Electrodynamics (QED). This equivalence holds for QED-RPA and a QED ring-CCD model.
Area of Science:
- Quantum Chemistry
- Quantum Electrodynamics
- Computational Physics
Background:
- The ground-state correlation energy from the particle-hole channel of the Random Phase Approximation (RPA) is formally equivalent to a simplified Coupled Cluster Doubles (CCD) model.
- This equivalence is based on ring-diagram contributions in the residual equations.
Purpose of the Study:
- To generalize the analytic equivalence between RPA and CCD to the cavity Quantum Electrodynamics (QED) framework.
- To demonstrate the numerical equivalence of QED-RPA and a QED ring-CCD model.
Main Methods:
- Generalization of analytic results from standard quantum chemistry to cavity QED.
- Numerical demonstration of equivalence between QED-RPA and a QED ring-CCD model.
Main Results:
- The study establishes the formal equivalence between QED-RPA and a QED ring-CCD model.
- The QED ring-CCD model accounts for double electron excitations, coupled single-electron/single-photon excitations, and double-photon creation.
Conclusions:
- The findings extend the known RPA-CCD equivalence to the domain of cavity QED.
- This provides a valuable connection between different theoretical models for describing quantum electrodynamic systems.
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