Open AccessCoupled cavity terahertz quantum cascade lasers with integrated emission monitoring
Author(s) -
Michael Krall,
M. Martl,
Dominic Bachmann,
C. Deutsch,
A. M. Andrews,
W. Schrenk,
G. Strasser,
K. Unterrainer
Publication year - 2015
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.003581
Subject(s) - terahertz radiation , laser , optics , optoelectronics , photomixing , cascade , terahertz spectroscopy and technology , semiconductor laser theory , quantum cascade laser , photon , waveguide , physics , far infrared laser , detector , materials science , terahertz metamaterials , chemistry , chromatography
We demonstrate the on-chip generation and detection of terahertz radiation in coupled cavity systems using a single semiconductor heterostructure. Multiple sections of a terahertz quantum cascade laser structure in a double-metal waveguide are optically coupled and operate either as a laser or an integrated emission monitor. A detailed analysis of the photon-assisted carrier transport in the active region below threshold reveals the detection mechanism for photons emitted by the very same structure above threshold. Configurations with a single laser cavity and two coupled laser cavities are studied. It is shown that the integrated detector can be used for spatial sensing of the light intensity within a coupled cavity.