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Matter coupling to strong electromagnetic fields in two-level quantum systems with broken inversion symmetry
O V Kibis1, G Ya Slepyan, S A Maksimenko
1Department of Applied and Theoretical Physics, Novosibirsk State Technical University, Karl Marx Avenue 20, 630092 Novosibirsk, Russia. Oleg.Kibis@nstu.ru
Physical Review Letters
|March 5, 2009
Summary
We show that quantum systems lacking inversion symmetry can act as parametric oscillators when exposed to strong electromagnetic fields. This enables frequency-tuned amplification and generation of electromagnetic waves, observable in III-nitride quantum dots.
Area of Science:
- Quantum optics
- Condensed matter physics
- Semiconductor nanostructures
Background:
- Two-level quantum systems are fundamental for quantum technologies.
- Broken inversion symmetry in quantum systems can lead to unique optical responses.
- Parametric oscillation is a key process for light amplification and generation.
Purpose of the Study:
- To theoretically investigate the parametric oscillator behavior of two-level quantum systems with broken inversion symmetry.
- To explore the potential for frequency-tuned parametric amplification and generation of electromagnetic waves.
- To discuss the experimental observability in III-nitride quantum dots.
Main Methods:
- Theoretical modeling of a two-level quantum system under a strong electromagnetic field.
- Analysis of scattered light spectrum and resonance frequencies.
- Investigation of Rabi frequency modifications and dipole radiation.
Main Results:
- Prediction of parametric oscillator behavior in asymmetric quantum systems.
- Identification of multiple resonance frequencies and harmonics in the scattered light.
- Demonstration of altered Rabi frequency and potential for dipole radiation at this frequency.
- Observation of terahertz emission from III-nitride quantum dot arrays.
Conclusions:
- Broken inversion symmetry enables parametric oscillation in quantum systems.
- This effect allows for tunable amplification and generation of electromagnetic waves.
- III-nitride quantum dots exhibit this phenomenon, leading to observable terahertz emission.
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