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Theory of parametric amplification in in superlattices

Timo Hyart·Alexey V. Shorokhov·Kirill N. Alekseev
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Abstract

We consider a high-frequency response of electrons in a single miniband of superlattice subject to dc and ac electric fields. We show that Bragg reflections in miniband result in a parametric resonance which is detectable using ac probe field. We establish theoretical feasibility of phase-sensitive THz amplification at the resonance. The parametric amplification does not require operation in conditions of negative differential conductance. This prevents a formation of destructive high-field domains inside the superlattice.

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Timo Hyart, Alexey V. Shorokhov, Kirill N. Alekseev. 2007-06-08. Theory of parametric amplification in in superlattices. https://doi.org/10.1103/physrevlett.98.220404

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