Ren, Y. and Wallis, R. and Shah, Y. D. and Jessop, D. S. and Degl'Innocenti, Riccardo and Klimont, A. and Kamboj, V. and Beere, H. E. and Ritchie, D. A. (2014) Single mode terahertz quantum cascade amplifier. Applied Physics Letters, 105 (14). ISSN 0003-6951
Full text not available from this repository.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.