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Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Strong coupling theory for the Jaynes-Cummings-Hubbard model
Physical Review Letters
|October 2, 2009
Summary
We developed a strong-coupling approach to study polariton superfluid-insulator transitions. Our method reveals four excitation modes in the Mott phase and calculates the phase boundary, including quantum fluctuations.
Area of Science:
- Quantum optics
- Condensed matter physics
- Cavity quantum electrodynamics
Background:
- The Jaynes-Cummings-Hubbard model describes interacting polaritons in coupled cavities.
- Understanding the superfluid-insulator transition is crucial for quantum technologies.
Purpose of the Study:
- To present an analytic strong-coupling approach for the Jaynes-Cummings-Hubbard model.
- To investigate the phase diagram and elementary excitations of polariton systems.
Main Methods:
- Analytic strong-coupling approach.
- Random-phase approximation (RPA) for dispersion and spectral weights.
- Inclusion of quantum fluctuations for phase boundary calculation.
Main Results:
- Identified four distinct excitation modes (lower and upper polaritons, particle/hole) in the Mott phase.
- Derived simple formulas for excitation dispersion and spectral weights.
- Calculated the phase boundary beyond RPA, incorporating quantum fluctuations.
Conclusions:
- The strong-coupling approach provides an effective framework for analyzing polariton systems.
- Quantum fluctuations play a significant role in determining the phase boundary.
- The findings offer insights into controlling quantum phases in coupled cavity arrays.
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