Extraction-Dominated Temperature Degradation of Population Inversion in Terahertz Quantum Cascade Lasers.
Sign Up to like & getrecommendations! Published in 2022 at "Small"
DOI: 10.1002/smll.202106943
Abstract: Degraded population inversion (PI) at elevated temperature, regarded as an important temperature degradation factor in terahertz quantum cascade lasers (THz QCL), has hindered the widespread use of these devices. Herein, the mechanism of the temperature… read more here.
Keywords: population inversion; temperature degradation; extraction; terahertz quantum ... See more keywords
Effects of propagation on the population dynamics of terahertz quantum cascade lasers
Sign Up to like & getrecommendations! Published in 2019 at "Superlattices and Microstructures"
DOI: 10.1016/j.spmi.2019.106315
Abstract: Abstract The spatial and temporal dependence of population dynamics caused by ultrafast π laser pulses are studied by Maxwell-Bloch equations in terahertz quantum cascade lasers with and without propagation effects. It is shown that the… read more here.
Keywords: effects propagation; population dynamics; terahertz quantum; cascade lasers ... See more keywords
Enhanced operating temperature in terahertz quantum cascade lasers based on direct phonon depopulation
Sign Up to like & getrecommendations! Published in 2023 at "Applied Physics Letters"
DOI: 10.1063/5.0144705
Abstract: Room temperature operation of terahertz quantum cascade lasers (THz QCLs) has been a long-pursued goal to realize compact semiconductor THz sources. In this paper, we report on improving the maximum operating temperature of THz QCLs… read more here.
Keywords: cascade lasers; quantum cascade; terahertz quantum; temperature ... See more keywords
Terahertz Quantum Well Photodetectors With Metal-Grating Couplers
Sign Up to like & getrecommendations! Published in 2017 at "IEEE Journal of Selected Topics in Quantum Electronics"
DOI: 10.1109/jstqe.2016.2608618
Abstract: In this paper, terahertz (THz) quantum well photodetectors (QWPs) with metal-grating couplers are presented for normal-incident operation. Both one-dimensional and two-dimensional grating samples were fabricated. The photocurrent spectra and the peak responsivity were characterized. The… read more here.
Keywords: metal grating; photodetectors metal; grating couplers; terahertz quantum ... See more keywords
Distributed feedback 2.5-terahertz quantum cascade laser with high-power and single-mode emission
Sign Up to like & getrecommendations! Published in 2020 at "Optical Engineering"
DOI: 10.1117/1.oe.59.2.026109
Abstract: Abstract. The 2.5-terahertz quantum cascade lasers (THz QCLs) based on first-order distributed feedback (DFB) Bragg grating are reported. The loss and threshold gain within different grating duty cycles are calculated according to the mode-coupling theory.… read more here.
Keywords: terahertz quantum; distributed feedback; single mode; quantum cascade ... See more keywords
Terahertz quantum sensing
Sign Up to like & getrecommendations! Published in 2020 at "Science Advances"
DOI: 10.1126/sciadv.aaz8065
Abstract: Quantum sensing enables the measurement of sample properties in the terahertz frequency range by detecting visible photons. Quantum sensing is highly attractive for accessing spectral regions in which the detection of photons is technically challenging:… read more here.
Keywords: quantum; detection; range; quantum sensing ... See more keywords
Energy spectrum and thermal properties of a terahertz quantum-cascade laser based on the resonant-phonon depopulation scheme
Sign Up to like & getrecommendations! Published in 2017 at "Semiconductors"
DOI: 10.1134/s106378261704008x
Abstract: The dependences of the electronic-level positions and transition oscillator strengths on an applied electric field are studied for a terahertz quantum-cascade laser (THz QCL) with the resonant-phonon depopulation scheme, based on a cascade consisting of… read more here.
Keywords: quantum; resonant phonon; phonon depopulation; terahertz quantum ... See more keywords
Frequency stabilization of a terahertz quantum-cascade laser to the Lamb dip of a molecular absorption line.
Sign Up to like & getrecommendations! Published in 2023 at "Optics express"
DOI: 10.1364/oe.483883
Abstract: We demonstrate the frequency stabilization of a terahertz quantum-cascade laser (QCL) to the Lamb dip of the absorption line of a D2O rotational transition at 3.3809309 THz. To assess the quality of the frequency stabilization,… read more here.
Keywords: quantum cascade; stabilization; frequency; terahertz quantum ... See more keywords
Gas spectroscopy with integrated frequency monitoring through self-mixing in a terahertz quantum-cascade laser.
Sign Up to like & getrecommendations! Published in 2018 at "Optics letters"
DOI: 10.1364/ol.43.002225
Abstract: We demonstrate a gas spectroscopy technique, using self-mixing in a 3.4 terahertz quantum-cascade laser (QCL). All previous QCL spectroscopy techniques have required additional terahertz instrumentation (detectors, mixers, or spectrometers) for system pre-calibration or spectral analysis.… read more here.
Keywords: self mixing; gas; gas spectroscopy; spectroscopy ... See more keywords
Heterogeneous terahertz quantum cascade lasers exceeding 1.9 THz spectral bandwidth and featuring dual comb operation
Sign Up to like & getrecommendations! Published in 2017 at "Nanophotonics"
DOI: 10.1515/nanoph-2017-0024
Abstract: Abstract We report on a heterogeneous active region design for terahertz quantum cascade laser based frequency combs. Dynamic range, spectral bandwidth and output power have been significantly improved with respect to previous designs. When individually… read more here.
Keywords: comb operation; spectral bandwidth; terahertz quantum; comb ... See more keywords
Terahertz quantum cascade laser considering compositional interdiffusion effect
Sign Up to like & getrecommendations! Published in 2023 at "Applied Physics Express"
DOI: 10.35848/1882-0786/acc568
Abstract: This study presents an experimental demonstration of the crucial role of compositional interdiffusion at interfaces in GaAs/AlGaAs alternating superlattices for developing the terahertz quantum cascade lasers operating at high temperatures. By growing GaAs/Al0.3Ga0.7As superlattices using… read more here.
Keywords: compositional interdiffusion; interdiffusion; quantum cascade; quantum ... See more keywords