Tuning of the Spectral Characteristics of Terahertz Quantum-Cascade Lasers

R. A. Khabibullina,*, S. S. Pushkareva,**, R. R. Galieva, N. V. Shchavruka, I. N. Dyuzhikovb, V. V. Pavlovskiyb, and O. Yu. Volkovb

a Mokerov Institute of Ultra High Frequency Semiconductor Electronics, Russian Academy of Sciences, Moscow, 117105 Russia

b Kotel’nikov Institute of Radio Engineering and Electronics, Russian Academy of Sciences, Moscow, 125009 Russia

Correspondence to: *e-mail: khabibullin@isvch.ru
Correspondence to: **e-mail: s_s_e_r_p@mail.ru

Received 23 December, 2021

Abstract—Terahertz quantum-cascade lasers (THz QCLs) are promising radiation sources for high-resolution gas spectroscopy. A wide operating-frequency band (from 1.2 to 5.4 THz), a narrow generation line (up to 10 kHz), the ability to operate on several radiative transitions (two-color lasers, generation of frequency combs) and other unique characteristics of THz QCLs make it possible to create gas spectrometers of a new generation for biomedical and environmental applications. In this paper, we consider the possibility of controlling the spectral characteristics of THz QCLs by changing the operating temperature and injection-current pulse parameters: amplitude, duration, and repetition rate. The energy transfer between longitudinal Fabry–Perot modes in THz QCLs is studied for the first time with a change in the duty cycle of the injection-current pulse cycle.

Keywords: quantum-cascade laser, terahertz range, Fabry–Perot resonator, quantum well, molecular-beam epitaxy

DOI: 10.1134/S2635167622070102