Terahertz quantum-cascade lasers: Time domain spectroscopy and micro cavity effects

Author

Darmo, J. ; Fasching, G. ; Benz, A. ; Kroll, Josiane ; Martl, M. ; Dietze, D. ; Barbieri, S. ; Sirtori, C. ; Andrews, A.M. ; Schrenk, W. ; Strasser, G. ; Unterrainer, K.

Author_Institution

Inst. of Photonics, Vienna Univ. of Technol., Vienna

fYear

2008

fDate

15-19 Sept. 2008

Firstpage

1

Lastpage

2

Abstract

We have combined few-cycle THz spectroscopy with quantum cascade technology. This combination allows to perform unique THz time-domain measurements of THz-QCLs. By coupling the few-cycle THz pulse into the waveguide of the QCL, the processes within the active zone can be probed. This gives direct information regarding the energy, dynamics and coherence of transitions in the QCL structure. In addition, we will present micro-cavity quantum-cascade lasers emitting in the THz region. Strong mode confinement in the growth and in-plane directions are provided by a double-plasmon waveguide. We observe whispering-gallery modes and the threshold currents are smaller than from Fabry-Perot cavities; In the detailed study of the emission we were able to observe dynamical frequency pulling effects.

Keywords

microcavity lasers; plasmons; quantum cascade lasers; stimulated emission; submillimetre wave lasers; submillimetre wave spectroscopy; waveguide lasers; whispering gallery modes; Fabry-Perot cavities; double-plasmon waveguide; dynamical frequency pulling effects; few-cycle terahertz spectroscopy; microcavity effects; microcavity lasers; mode confinement; quantum-cascade lasers; stimulated emission; terahertz lasers; time domain spectroscopy; whispering-gallery modes; Coherence; Laser modes; Laser transitions; Performance evaluation; Quantum cascade lasers; Spectroscopy; Submillimeter wave technology; Time domain analysis; Waveguide lasers; Whispering gallery modes;

fLanguage

English

Publisher

ieee

Conference_Titel

Infrared, Millimeter and Terahertz Waves, 2008. IRMMW-THz 2008. 33rd International Conference on

Conference_Location

Pasadena, CA

Print_ISBN

978-1-4244-2119-0

Electronic_ISBN

978-1-4244-2120-6

Type

conf

DOI

10.1109/ICIMW.2008.4665581

Filename

4665581