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Cerenkov generation of high-frequency confined acoustic phonons in quantum wells

S. M. Komirenko·K. W. Kim·A. A. Demidenko·V. A. Kochelap·M. A. Stroscio
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Abstract

We analyze the Cerenkov emission of high-frequency confined acoustic phonons by drifting electrons in a quantum well. We find that the electron drift can cause strong phonon amplification (generation). A general formula for the gain coefficient, alpha, is obtained as a function of the phonon frequency and the structure parameters. The gain coefficient increases sharply in the short-wave region. For the example of a Si/SiGe/Si device it is shown that the amplification coefficients of the order of hundreds of 1/cm can be achieved in the sub-THz frequency range.

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S. M. Komirenko, K. W. Kim, A. A. Demidenko, V. A. Kochelap, M. A. Stroscio. 1999-11-23. Cerenkov generation of high-frequency confined acoustic phonons in quantum wells. https://doi.org/10.1063/1.126195

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