Share Email Print

Proceedings Paper

High-performance broadly-tunable THz quantum cascade laser sources based on intracavity difference-frequency mixing on silicon substrates (Conference Presentation)
Author(s): Mikhail A. Belkin

Paper Abstract

We demonstrate that an application of a III-V-on-silicon hybrid concept to terahertz (THz) Cherenkov difference frequency generation (DFG) quantum cascade laser (QCL) sources (THz DFG-QCLs) can dramatically improve THz output power and mid-infrared-to-THz conversion efficiency. Completely processed THz DFG-QCLs grown on a InP substrate are transfer-printed onto a 1-mm-thick high-resistive Si substrate using a 100-nm-thick SU-8 as an adhesive layer. Room temperature device performance of the reference InP and hybrid Si THz DFG-QCLs of the same ridge width (22 µm) and cavity length (4.2 mm) have been experimentally compared. The target THz frequency of 3.5 THz is selected for both devices using the dual-period first order surface gratings to select the mid-infrared pump wavelength of 994 cm-1 and 1110 cm-1. At the maximum bias current, the reference InP and hybrid Si devices produced THz power of 50 µW and 270 µW, respectively. The mid-infrared-to-THz conversion efficiency corresponds to 60 µW/W2 and 480 µW/W2, respectively, resulting in 5 times higher THz power and 8 times higher conversion efficiency from the best-performing hybrid devices. A hybrid Si device integrated in a Littrow external-cavity setup showed wavelength tuning in the 1-6 THz range without THz beam steering.

Paper Details

Date Published: 19 September 2017
Proc. SPIE 10383, Terahertz Emitters, Receivers, and Applications VIII, 1038307 (19 September 2017); doi: 10.1117/12.2275014
Show Author Affiliations
Mikhail A. Belkin, The Univ. of Texas at Austin (United States)

Published in SPIE Proceedings Vol. 10383:
Terahertz Emitters, Receivers, and Applications VIII
Manijeh Razeghi; Alexei N. Baranov; Dimitris Pavlidis; John M. Zavada, Editor(s)

© SPIE. Terms of Use
Back to Top