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arXiv · 1606.09125

Multiple quantum wells for PT-symmetric phononic crystals

A. V. Poshakinskiy·A. N. Poddubny·A. Fainstein
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Abstract

We demonstrate that the parity-time symmetry for sound is realized in the laser-pumped multiple-quantum-well structure. Breaking of the parity-time symmetry for the phonons with wave vectors corresponding to the Bragg condition makes the structure a highly-selective acoustic wave amplifier. Single-mode distributed feedback phonon lasing is predicted for structures with realistic parameters.

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A. V. Poshakinskiy, A. N. Poddubny, A. Fainstein. 2016-06-29. Multiple quantum wells for PT-symmetric phononic crystals. https://doi.org/10.1103/physrevlett.117.224302

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