quantum cascade laser structure
Dynamics of a vertical cavity quantum cascade phonon laser structure
... band structure of the SL, shown in Fig. 1a, consists of quantum wells for electrons in GaAs, separated by narrow AlAs ...can quantum mechanically tunnel through the barriers and occupy an electronic ...
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Efficient prediction of terahertz quantum cascade laser dynamics from steady state simulations
... region structure as described in ...V)-dependent laser parameters were determined using our full RE model in a grid of 13 tem- peratures and 38 electric field values, giving a total of 494 grid point values ...
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Tapered Quantum Cascade Laser Arrays Integrated with Talbot Cavities
... accumulation. Taper structure is one of the best methods to increase the filling factor at the same time ensuring a fundamental mode operation of the single ridge itself. In this letter, taper structures are ...
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3.5 THz quantum-cascade laser emission from dual diagonal feedhorns
... antenna structure offers the possibility of enhancing the QCL output signal by constraining it to a propagation mode that results in improved beam quality, and simultaneously allows coupling to a mixer diode ...
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Line defect photonic crystal terahertz quantum cascade laser
... Introducing a series of defects in the photonic lattice allows waveguiding, due to the conservation of crystal momentum. The modes supported by the defect are normally classi fi ed depending on the E-field nodes in the ...
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Continuous wave room temperature external ring cavity quantum cascade laser
... coating was achieved by using two layered structure of mixed metal fluoride and ZnSe materials. These AR coatings are expected to provide strong suppression of the Fabry Perot (FP) modes of the laser ridge. ...
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Photonic quasi-crystal terahertz lasers
... Fourier structure 11 of quasi-crystalline materials, with or without a photonic bandgap, can be exploited in a laser cavity to engineer the mode frequency and spacing separately, or to control the emission ...
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3.5-THz quantum-cascade laser emission from dual diagonal feedhorns
... into the same block at each end of the waveguide. After machining, the block was gold plated to prevent corrosion and to improve thermal heat sinking to a cryogenic cooler. Bias connection to the QCL was achieved through ...
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Broadband terahertz gas spectroscopy through multimode self-mixing in a quantum cascade laser
... metal (DM) ridge-waveguide structure. Ti/Au of thickness 10/500 nm was deposited on top of the QCL wafer, and also on a second n+-GaAs acceptor wafer. The two wafers were then thermal compression bonded at the ...
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Three-dimensional terahertz imaging using swept-frequency feedback interferometry with a quantum cascade laser
... Coherent 3D imaging was demonstrated using exemplar GaAs structures [9] that were fabricated by wet chemical etching. The sample comprised three stepped regions (in the X-direction) with a nominal step height 10 µm and a ...
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Optical Breadboard Integration of a 3.5-THz Quantum-Cascade Laser Local-Oscillator for the LOCUS Atmospheric Sounder
... A separate QCL was subsequently solder-mounted within a precision micro-machined 130-µm- wide × 75-µm-deep channel within an oxygen-free copper enclosure (Fig. 4:left), and ribbon-bonded to an integrated SMA connector. A ...
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Electron-phonon relaxation rates and optical gain in a quantum cascade laser in a magnetic field
... AlGaAs quantum cascade laser in a magnetic field, based on solving the set of rate equations that describe the carrier density in each level, accounting for the optical- and acoustic-phonon ...
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Coherent three-dimensional terahertz imaging through self-mixing in a quantum cascade laser
... Coherent 3D imaging was performed on exemplar GaAs structures that were fabricated by wet chemical etching. Sample A comprised of three stepped regions (in the X-direc- tion) with a nominal step height 10 lm and a width ...
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Theoretical Investigation of Electronic and Optical Properties of Si/SiGe Quantum Cascade Structures
... QC laser indicates that electrons are solely responsible for releasing energy in the form of ...one quantum energy state to another within a layer, or group of layers, of semiconductor material releasing ...
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Density matrix superoperator for periodic quantum systems and its application to quantum cascade laser structures
... Boundary conditions represent the crucial part of the system formulation. In this work we focused on periodic systems described by the banded partitioned Hamiltonian, but the effects of device boundaries will generally ...
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Self-consistent solutions to the intersubband rate equations in quantum cascade lasers: Analysis of a GaAs/AlxGa1-xAs device
... between subbands 3 and 2. This has been used to give an indication of the potential for a device to reach a population inversion and works well in, for example, mid-infrared de- vices where the energy gaps are relatively ...
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Injection locking of a terahertz quantum cascade laser to a telecommunications wavelength frequency comb
... In the spectral region from 1.5 to 5 THz, however, the power available from frequency multiplier chains becomes impracticably small, and, as such, the most promising source is the THz quan- tum cascade ...
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Purity monitoring in medical gas supply lines with quantum cascade laser technology
... narrow laser-line width of the QCL and the capability to scan across the respective target spectrum with the highest spectral resolution, which makes it preferable under lower pressure conditions of a few hundred ...
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Silicon germanium materials for terahertz emission
... the structure. Cross-sectional TEM was then performed on the structure and the thickness of each layer found by taking the absolute differential of relative intensity and the results used to plot growth ...
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Quantum cascade laser-based mid-infrared spectrochemical imaging of tissue and biofluids
... tunable laser based microscope has conversely allowed the focused acquisition of 14 pertinent mid-infrared spectral features required for classification, representing a step change in spectral image collection ...
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