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High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
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Multiple Quantum Wells for PT-Symmetric Phononic Crystals.
A V Poshakinskiy1, A N Poddubny1, A Fainstein2
1Ioffe Institute, St. Petersburg 194021, Russia.
Physical Review Letters
|December 8, 2016
Summary
We achieved parity-time symmetry for sound in laser-pumped quantum wells. Breaking this symmetry creates a selective acoustic amplifier, enabling phonon lasing.
Area of Science:
- Acoustics
- Quantum Optics
- Condensed Matter Physics
Background:
- Parity-time (PT) symmetry is a theoretical concept in quantum mechanics.
- PT symmetry has been experimentally realized in various optical and mechanical systems.
- Quantum-well structures offer a platform for exploring novel wave phenomena.
Purpose of the Study:
- To demonstrate the realization of parity-time symmetry for sound waves.
- To investigate the breaking of PT symmetry in acoustic systems.
- To explore the potential for acoustic amplification and lasing.
Main Methods:
- Utilizing laser-pumped multiple-quantum-well structures.
- Analyzing phonon behavior under Bragg conditions.
- Theoretical prediction of phonon lasing.
Main Results:
- Successful demonstration of parity-time symmetry for sound.
- Observation of PT symmetry breaking leading to selective acoustic amplification.
- Prediction of single-mode distributed feedback phonon lasing.
Conclusions:
- Laser-pumped quantum wells can host PT-symmetric acoustic systems.
- PT symmetry breaking is a viable mechanism for acoustic amplification.
- Phonon lasing is achievable in realistic PT-symmetric structures.
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