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DOE OSTI · 22350839

Single mode terahertz quantum cascade amplifier

Wallis, R.·Shah, Y. D.·Jessop, D. S.·Degl'Innocenti, R.·Klimont, A.·Kamboj, V.·Beere, H. E.·Ritchie, D. A.
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Abstract

A terahertz (THz) optical amplifier based on a 2.9 THz quantum cascade laser (QCL) structure has been demonstrated. By depositing an antireflective coating on the QCL facet, the laser mirror losses are enhanced to fully suppress the lasing action, creating a THz quantum cascade (QC) amplifier. Terahertz radiation amplification has been obtained, by coupling a separate multi-mode THz QCL of the same active region design to the QC amplifier. A bare cavity gain is achieved and shows excellent agreement with the lasing spectrum from the original QCL without the antireflective coating. Furthermore, a maximum optical gain of ∼30 dB with single-mode radiation output is demonstrated.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYAMPLIFIERSANTIREFLECTION COATINGSCOUPLINGCRYSTAL DEFECTSGAINLASER MIRRORSLASERSLOSSESSPECTRATHZ RANGE

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Wallis, R., Shah, Y. D., Jessop, D. S., Degl'Innocenti, R., Klimont, A., Kamboj, V., Beere, H. E., Ritchie, D. A.. 2014-10-06. Single mode terahertz quantum cascade amplifier. https://doi.org/10.1063/1.4897438

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