[PDF] Top 20 Design Optimization for 4.1-THZ Quantum Cascade Lasers

... Abstract: We present an optimized design for GaAs/AlGaAs quantum cascade lasers operating at 4.1THz. This was based on a three-well active module with diagonal radiative transition. This was ... See full document

... CC THz QCL with an active cavity length of ...CC THz QCL was driven by a series of current pulses with three different amplitudes of 0 A, ...2.794 THz, 2.766 THz, and 2.738 THz, ... See full document

... a 1 µm/hour growth rate for GaAs is plotted in ...of THz QCL growths, are also ...to THz QCL growths during the campaign – other device structures require different aluminum mole fractions, and were ... See full document

... Terahertz-frequency quantum cascade lasers (THz QCLs) are compact solid-state sources of coherent radiation in the 1–5 THz region of the electromagnetic spectrum [1], with ... See full document

... figure 1(a) for a simplified 3-level system and an II scheme with diagonal THz emission in figure 1(b) for a simplified 4- level system, which is used in this ...frequency THz QCLs ... See full document

... open for electrons to elastically scatter to energetically close levels. The relevant scattering rates are multiplied by the carrier densities and Fermi-Dirac terms, according to equation 11, to determine the modal gain, ... See full document

... Formed from a bandgap engineered semiconductor structure, the QCL used in this experimental work is based on a GaAs/AlGaAs phonon-assisted “hybrid” design [3]. The active region of the device has been grown using ... See full document

... bound-to-continuum design for a (111) Si/SiGe QCL and investigated several options for ...5 THz is possible up to a lattice temperature of 90 K, with a low-temperature current density of 2 kAcm −1 ... See full document

... emission was included self-consistently for the calculation of the I - V curve. A voltage drop of 2.5 V due to the Schottky barrier and a series contact resistance of 0.3 Ω were used to calibrate the measured I-V curve. ... See full document

... Sb-based quantum cascade structures as well as further improvements in the QCL design are re- quired to approach the goal of achieving above-room temper- ature near-infrared (λ ∼ 3µm) laser ... See full document

... Recently InGaAs/AlAsSb QCLs lattice matched to InP sub- strates have been reported [7]. The InGaAs/AlAsSb het- erostructure has a very large conduction band offset of ∼1.6 eV which is almost double that of the strained ... See full document

... 2.6 THz and ∼ 4.9 THz, respectively, have been ...of quantum engineering of the heterostructure and by exploiting the Stark effect; by using a shorter lasing cavity (∼2 mm) to increase the effective ... See full document

... Quantum Cascade Lasers (QCLs) are powerful intersub- band laser sources operating throughout the mid-infrared (MIR) 1 and terahertz (THz) 2 spectral ...a THz QCL were used to ... See full document

... cavity lasers, ...Fig. 4(a) for a 4 mm-long, 160 lm-wide ...2.50–2.55 THz, and a maximum lasing bandwidth of 150 GHz is observed close to the maximum emitted ... See full document

... the design and optimization of GaAs/ AlGaAs quantum cascade laser ...of design parameters that satisfy predefined conditions, leading to an enhancement of the device output ...important ... See full document

... improvements could be expected at even higher frequencies by using Ag-based waveguides. Lower waveguide loss is expected to result in better device performance. To quantify this improvement, the calculated optical peak ... See full document

... crucial design parameters, as well as an understanding of the relevant physical limitations of particular designs, it is highly desirable to investigate the influences of the relevant physi- cal and technological ... See full document

... delay and rise time are seen to increase non-linearly with increasing temperature, while the steady-state optical output power decreases and ceases altogether at ∼53 K. Because thermal effects take place on a microsecond ... See full document

... At a frequency of 3.5 THz, however, the dimensions of both waveguide and feedhorn challenge mechanical fabrication techni- ques. Thus, and in support of our radiometer concept, the viabil- ity of a diagonal ... See full document

... subbands 1, 2, 3, 5, and 7 in the col lec tor, and 8, 10, 11, 13, and 15 in the in jec ...Level 4 rep - re sents the ac tive re gion ground state which is lo cated one LO phonon en ergy be low the lower la ... See full document