Near-Full Current Dynamic Range THz Quantum Cascade Laser Frequency Comb

Yu Ma; Weijiang Li; Yuanyuan Li; Junqi Liu; Ning Zhuo; Ke Yang; Jinchuan Zhang; Shenqiang Zhai; Shuman Liu; Lijun Wang; Fengqi Liu

doi:10.3390/mi14020473

Near-Full Current Dynamic Range THz Quantum Cascade Laser Frequency Comb

Micromachines (Basel). 2023 Feb 18;14(2):473. doi: 10.3390/mi14020473.

Authors

Yu Ma^{1

2}, Weijiang Li^{1

2}, Yuanyuan Li^{1

2}, Junqi Liu^{1

2}, Ning Zhuo^{1

2}, Ke Yang^{1

2}, Jinchuan Zhang^{1

2}, Shenqiang Zhai^{1

2}, Shuman Liu^{1

2}, Lijun Wang^{1

2}, Fengqi Liu^{1

2}

Affiliations

¹ Key Laboratory of Semiconductor Materials Science, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083, China.
² Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.

Abstract

The present study proposes a terahertz quantum cascade laser frequency comb (THz QCL FC) with a semi-insulated surface plasma waveguide characterized by a low threshold current density, high power and a wide current dynamic range. The gain dispersion value and the nonlinear susceptibility were optimized based on the combination of a hybrid bound-to-continuum active region with a semi-insulated surface plasmon waveguide. Without any extra dispersion compensator, stable frequency comb operation within a current dynamic range of more than 97% of the total was revealed by the intermode beat note map. Additionally, a total comb spectral emission of about 300 GHz centered around 4.6 THz was achieved for a 3 mm long and 150 µm wide device. At 10 K, a maximum output power of 22 mW was obtained with an ultra-low threshold current density of 64.4 A·cm^-2.

Keywords: frequency comb; high power; low threshold current density; near-full current dynamic range; quantum cascade lasers; terahertz.

Abstract

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