Terahertz Quantum Cascade Devices: From Intersubband Transition to Microcavity Laser

Author

Unterrainer, K. ; Benz, A. ; Darmo, J. ; Deutsch, Ch ; Fasching, G. ; Kröll, J. ; Kelly, D.P. ; Martl, M. ; Muller, Tim ; Parz, W. ; Dhillon, S.S. ; Sirtori, C. ; Andrews, A.M. ; Schrenk, W. ; Strasser, G. ; Marcadet, X. ; Calligaro, M. ; Beere, H.E. ; Ri

Author_Institution

Vienna Univ. of Technol., Vienna

Volume

14

Issue

2

fYear

2008

Firstpage

307

Lastpage

314

Abstract

In this review, we report on the study of terahertz (THz) intersubband (ISB) transitions and on the optical devices based on them. We use time-resolved THz spectroscopy to examine ISB optical transitions in semiconductor quantum wells and quantum cascade lasers (QCLs). From these measurements, we obtain important information on the carrier relaxation, scattering mechanisms, and the gain. The waveguide losses are studied directly on the QCL devices and we show the main loss mechanism in the double-metal waveguides. Finally, we demonstrate THz-QCLs with low-mode volume optical cavity.

Keywords

light scattering; microcavity lasers; optical losses; quantum cascade lasers; submillimetre wave lasers; submillimetre wave spectra; time resolved spectra; waveguide lasers; carrier relaxation; double-metal waveguides; intersubband transition; low-mode volume optical cavity; microcavity laser; optical devices; optical gain; optical transitions; quantum cascade devices; quantum cascade lasers; scattering mechanisms; semiconductor quantum wells; terahertz devices; terahertz spectroscopy; time-resolved spectroscopy; waveguide losses; Laser transitions; Microcavities; Optical devices; Optical losses; Optical scattering; Optical waveguides; Quantum cascade lasers; Quantum well lasers; Semiconductor lasers; Semiconductor waveguides; Carrier dynamics; semiconductor heterostructures; terahertz (THz) quantum cascade lasers (QCLs); time-domain THz spectroscopy;

fLanguage

English

Journal_Title

Selected Topics in Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

1077-260X

Type

jour

DOI

10.1109/JSTQE.2008.915528

Filename

4481134