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Tunable terahertz emission from difference-frequency in biased superlattices

Ren-Bao Liu·Bang-Fen Zhu
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Abstract

The terahertz emission from difference-frequency in biased superlattices is calculated with the excitonic effect included. Owing to the doubly resonant condition and the excitonic enhancement, the typical susceptibility can be as large as $10^{-5}$ m/V. The doubly resonant condition can always be realized by adjusting the bias voltage and the laser frequencies, thus the in-situ tunable emission is efficient in a range of several terahertz. Continuous wave operation with 1% quantum efficiency and $μ$W output power is feasible as the signal absorption in undoped superlattices is negligible.

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Ren-Bao Liu, Bang-Fen Zhu. 2003-11-20. Tunable terahertz emission from difference-frequency in biased superlattices. https://doi.org/10.1063/1.1703849

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