Quantum derivatives and high-frequency gain in semiconductor superlattices

A. V. Shorokhov; K. N. Alekseev

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arXiv · cond-mat/0602546

Quantum derivatives and high-frequency gain in semiconductor superlattices

A. V. Shorokhov·K. N. Alekseev

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Abstract

We derive simple difference formulas describing a small-signal absorption of THz field in a semiconductor superlattice driven by a microwave pump. We give a transparent geometric interpretation of these formulas that allows a search of optimum conditions for the gain employing only a simple qualitative analysis. Our theoretical approach provides a powerful tool for finding the correspondence between quasistatic and dynamic regimes in ac-driven semiconductor superlattices.

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A. V. Shorokhov, K. N. Alekseev. 2006-02-23. Quantum derivatives and high-frequency gain in semiconductor superlattices. https://arxiv.org/abs/cond-mat/0602546

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