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Strong Coupling Optomechanics Mediated by a Qubit in the Dispersive Regime
Ahmad Shafiei Aporvari1,2, David Vitali1,3,4
1School of Science and Technology, Physics Division, University of Camerino, I-62032 Camerino, Italy.
Entropy (Basel, Switzerland)
|August 27, 2021
Summary
Cavity optomechanics uses Josephson circuits to significantly enhance single-photon coupling for quantum technologies. This research details how an off-resonant qubit mediates this interaction, enabling strong coupling regimes for advanced quantum applications.
Area of Science:
- Quantum physics
- Quantum optics
- Condensed matter physics
Background:
- Cavity optomechanics is a key platform for quantum technologies like quantum interfaces and sensors.
- The inherent single-photon optomechanical coupling is typically weak, limiting nonlinear dynamics and quantum control.
- Josephson circuits can mediate interactions to greatly enhance this coupling.
Purpose of the Study:
- To analyze the phenomenon of enhanced single-photon optomechanical coupling mediated by a Josephson circuit.
- To investigate this enhancement in a general case involving an off-resonant qubit.
- To determine the conditions for achieving a strong coupling regime in this tripartite system.
Main Methods:
- Theoretical analysis of a tripartite hybrid system (cavity mode, mechanical mode, qubit).
- Application of the Schrieffer-Wolff approximation.
- Determination of the effective cavity optomechanical system parameters.
Main Results:
- Demonstration of a significant enhancement in single-photon optomechanical coupling.
- Identification of the regime where the tripartite system effectively functions as a strongly coupled optomechanical system.
- The off-resonant qubit acts as a crucial mediator for this enhanced interaction.
Conclusions:
- The use of an off-resonant qubit provides a powerful method to achieve strong coupling in cavity optomechanics.
- This approach opens new avenues for developing advanced quantum technologies.
- The findings are crucial for realizing enhanced quantum interfaces, sensors, and information processing.
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