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Lasing without inversion in circuit quantum electrodynamics
M Marthaler1, Y Utsumi, D S Golubev
1Institut für Theoretische Festkörperphysik, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany.
Physical Review Letters
|September 21, 2011
Summary
We demonstrate "lasing without inversion" in a qubit-oscillator system. Dissipation enhances photon emission, enabling lasing even without population inversion, a potentially observable effect in quantum circuits.
Area of Science:
- Quantum Optics
- Circuit Quantum Electrodynamics
Background:
- Population inversion in a qubit-coupled oscillator can induce lasing.
- Previous studies focused on population inversion for lasing phenomena.
Purpose of the Study:
- Investigate photon generation in a qubit-oscillator system with dissipation.
- Explore the possibility of achieving lasing without population inversion.
Main Methods:
- Theoretical analysis of a transmission line oscillator coupled to a driven qubit.
- Modeling the influence of a dissipative electromagnetic environment.
Main Results:
- Demonstrated a novel
- lasing without inversion
- regime.
Conclusions:
- The dissipative environment enhances photon emission over absorption, enabling lasing without population inversion.
- This effect is analogous to the atomic recoil effect but is expected to be more observable in realistic quantum circuits.
- Analysis provides requirements for system parameters and environment for experimental realization.
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