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Showing papers on "Quantum well published in 2011"


Journal ArticleDOI
TL;DR: In this paper, a broad review of fundamental electronic properties of two-dimensional graphene with the emphasis on density and temperature dependent carrier transport in doped or gated graphene structures is provided.
Abstract: We provide a broad review of fundamental electronic properties of two-dimensional graphene with the emphasis on density and temperature dependent carrier transport in doped or gated graphene structures. A salient feature of our review is a critical comparison between carrier transport in graphene and in two-dimensional semiconductor systems (e.g. heterostructures, quantum wells, inversion layers) so that the unique features of graphene electronic properties arising from its gap- less, massless, chiral Dirac spectrum are highlighted. Experiment and theory as well as quantum and semi-classical transport are discussed in a synergistic manner in order to provide a unified and comprehensive perspective. Although the emphasis of the review is on those aspects of graphene transport where reasonable consensus exists in the literature, open questions are discussed as well. Various physical mechanisms controlling transport are described in depth including long- range charged impurity scattering, screening, short-range defect scattering, phonon scattering, many-body effects, Klein tunneling, minimum conductivity at the Dirac point, electron-hole puddle formation, p-n junctions, localization, percolation, quantum-classical crossover, midgap states, quantum Hall effects, and other phenomena.

2,930 citations


Journal ArticleDOI
TL;DR: This analysis shows strong evidence for the existence of helical edge modes proposed by Liu et al, which persist in spite of sizable bulk conduction and show only a weak magnetic field dependence.
Abstract: We present an experimental study of low temperature electronic transport in the hybridization gap of inverted InAs/GaSb composite quantum wells. An electrostatic gate is used to push the Fermi level into the gap regime, where the conductance as a function of sample length and width is measured. Our analysis shows strong evidence for the existence of helical edge modes proposed by Liu et al [Phys. Rev. Lett. 100, 236601 (2008)]. Edge modes persist in spite of sizable bulk conduction and show only a weak magnetic field dependence-a direct consequence of a gap opening away from the zone center.

790 citations


Journal ArticleDOI
TL;DR: In this paper, the authors theoretically study the generic behavior of the penetration depth of the edge states in two-dimensional quantum spin Hall systems and show that the momentum-space width of edge-state dispersion scales with the inverse of penetration depth.
Abstract: We theoretically study the generic behavior of the penetration depth of the edge states in two-dimensional quantum spin Hall systems. We found that the momentum-space width of the edge-state dispersion scales with the inverse of the penetration depth. As an example of well-localized edge states, we take the Bi(111) ultrathin film. Its edge states are found to extend almost over the whole Brillouin zone. Correspondingly, the bismuth (111) 1-bilayer system is proposed to have well-localized edge states in contrast to the HgTe quantum well.

289 citations


Journal ArticleDOI
Ting Wang1, Huiyun Liu1, AC Lee1, F Pozzi1, Alwyn J. Seeds1 
TL;DR: An investigation on the development of InGaAs/GaAs strained-layer superlattices as DFLs for 1.3-μm InAs/ GaAs quantum-dot lasers monolithically grown on a Si substrate is presented.
Abstract: We report the first operation of an electrically pumped 1.3-μm InAs/GaAs quantum-dot laser epitaxially grown on a Si (100) substrate. The laser structure was grown directly on the Si substrate by molecular beam epitaxy. Lasing at 1.302 μm has been demonstrated with threshold current density of 725 A/cm2 and output power of ~26 mW for broad-area lasers with as-cleaved facets at room temperature. These results are directly attributable to the optimized growth temperature of the initial GaAs nucleation layer.

244 citations


Posted Content
TL;DR: In this paper, the authors provide a blueprint for stabilizing a robust topological insulator (TIs) in a more readily available two-dimensional material (graphene) using symmetry arguments, density functional theory, and tight-binding simulations.
Abstract: The 2007 discovery of quantized conductance in HgTe quantum wells delivered the field of topological insulators (TIs) its first experimental confirmation. While many three-dimensional TIs have since been identified, HgTe remains the only known two-dimensional system in this class. Difficulty fabricating HgTe quantum wells has, moreover, hampered their widespread use. With the goal of breaking this logjam we provide a blueprint for stabilizing a robust TI state in a more readily available two-dimensional material---graphene. Using symmetry arguments, density functional theory, and tight-binding simulations, we predict that graphene endowed with certain heavy adatoms realizes a TI with substantial band gap. For indium and thallium, our most promising adatom candidates, a modest 6% coverage produces an estimated gap near 80K and 240K, respectively, which should be detectable in transport or spectroscopic measurements. Engineering such a robust topological phase in graphene could pave the way for a new generation of devices for spintronics, ultra-low-dissipation electronics and quantum information processing.

218 citations


Journal ArticleDOI
TL;DR: These radial nonpolar quantum wells used in room-temperature single-wire electroluminescent devices emitting at 392 nm by exploiting sidewall emission demonstrating the absence of the quantum Stark effect as expected due to the non polar orientation.
Abstract: Nonpolar InGaN/GaN multiple quantum wells (MQWs) grown on the {1100} sidewalls of c-axis GaN wires have been grown by organometallic vapor phase epitaxy on c-sapphire substrates. The structural properties of single wires are studied in detail by scanning transmission electron microscopy and in a more original way by secondary ion mass spectroscopy to quantify defects, thickness (1–8 nm) and In-composition in the wells (∼16%). The core–shell MQW light emission characteristics (390–420 nm at 5 K) were investigated by cathodo- and photoluminescence demonstrating the absence of the quantum Stark effect as expected due to the nonpolar orientation. Finally, these radial nonpolar quantum wells were used in room-temperature single-wire electroluminescent devices emitting at 392 nm by exploiting sidewall emission.

199 citations


Journal ArticleDOI
TL;DR: In this article, a green GaInN/GaN quantum well light-emitting diode (LED) wafers were grown on nanopatterned c-plane sapphire substrate by metal-organic vapor phase epitaxy.
Abstract: Green GaInN/GaN quantum well light-emitting diode (LED) wafers were grown on nanopatterned c-plane sapphire substrate by metal-organic vapor phase epitaxy. Without roughening the chip surface, such LEDs show triple the light output over structures on planar sapphire. By quantitative analysis the enhancement was attributed to both, enhanced generation efficiency and extraction. The spectral interference and emission patterns reveal a 58% enhanced light extraction while photoluminescence reveals a doubling of the internal quantum efficiency. The latter was attributed to a 44% lower threading dislocation density as observed in transmission electron microscopy. The partial light output power measured from the sapphire side of the unencapsulated nanopatterned substrate LED die reaches 5.2 mW at 525 nm at 100 mA compared to 1.8 mW in the reference LED.

194 citations


Journal ArticleDOI
TL;DR: In this paper, the authors calculated the localization lengths of the electrons and holes in InGaN/GaN quantum wells using numerical solutions of the effective mass Schrodinger equation.
Abstract: Localization lengths of the electrons and holes in InGaN/GaN quantum wells have been calculated using numerical solutions of the effective mass Schrodinger equation. We have treated the distribution of indium atoms as random and found that the resultant fluctuations in alloy concentration can localize the carriers. By using a locally varying indium concentration function we have calculated the contribution to the potential energy of the carriers from band gap fluctuations, the deformation potential, and the spontaneous and piezoelectric fields. We have considered the effect of well width fluctuations and found that these contribute to electron localization, but not to hole localization. We also simulate low temperature photoluminescence spectra and find good agreement with experiment.

171 citations


Journal ArticleDOI
TL;DR: The concept of an exciton-polariton expresses the nonperturbative coupling between the electromagnetic field and the optically induced matter polarization as discussed by the authors, which is a measure of a semiconductor's coupling to an optical field.
Abstract: The integrated absorption of an excitonic resonance is a measure of a semiconductor's coupling to an optical field. The concept of an exciton–polariton expresses the non-perturbative coupling between the electromagnetic field and the optically induced matter polarization. Ways to alter this coupling include confining the light in optical cavities and localizing the excitonic wavefunction in quantum wells and dots, which is illustrated by quantum strong coupling between a single dot and an optical nanocavity. Positioning quantum wells in periodic or quasiperiodic lattices with spacing close to a half wavelength results in pronounced modifications to the light transmission. Light–matter coupling can also be used to generate and interrogate an exciton population, for example by the recently developed technique of absorbing terahertz radiation.

169 citations


Journal ArticleDOI
TL;DR: In this paper, the authors discuss recent progress in the field of quantum dot devices, including the development of electrically operated emitters of single polarized or entangled photons on demand: an essential component for quantum communication systems.

163 citations


Journal ArticleDOI
TL;DR: In this paper, the spectral imaging in the UV to visible range with nanometer scale resolution of closely packed GaN/AlN quantum disks in individual nanowires using an improved custom-made cathodoluminescence system is presented.
Abstract: We report the spectral imaging in the UV to visible range with nanometer scale resolution of closely packed GaN/AlN quantum disks in individual nanowires using an improved custom-made cathodoluminescence system. We demonstrate the possibility to measure full spectral features of individual quantum emitters as small as 1 nm and separated from each other by only a few nanometers and the ability to correlate their optical properties to their size, measured with atomic resolution. The direct correlation between the quantum disk size and emission wavelength provides evidence of the quantum confined Stark effect leading to an emission below the bulk GaN band gap for disks thicker than 2.6 nm. With the help of simulations, we show that the internal electric field in the studied quantum disks is smaller than what is expected in the quantum well case. We show evidence of a clear dispersion of the emission wavelengths of different quantum disks of identical size but different positions along the wire. This dispersi...

Patent
01 Sep 2011
TL;DR: In this paper, a method for manufacturing a semiconductor device, by which a multiple quantum well structure having a large number of pairs can be efficiently grown while maintaining good crystalline quality, and the semiconductor devices, are provided.
Abstract: A method for manufacturing a semiconductor device, by which a multiple quantum well structure having a large number of pairs can be efficiently grown while maintaining good crystalline quality, and the semiconductor device, are provided. The semiconductor device manufacturing method of the present invention includes a step of forming a multiple quantum well structure 3 having 50 or more pairs of group III-V compound semiconductor quantum wells. In the step of forming the multiple quantum well structure 3, the multiple quantum well structure is formed by metal-organic vapor phase epitaxy using only metal-organic sources (all metal-organic source MOVPE).

Journal ArticleDOI
TL;DR: In this article, the gain characteristics of high Al-content AlGaN-delta-GaN quantum wells (QWs) are investigated for mid and deep-ultraviolet (UV) lasers.
Abstract: The gain characteristics of high Al-content AlGaN-delta-GaN quantum wells (QWs) are investigated for mid- and deep-ultraviolet (UV) lasers. The insertion of an ultrathin GaN layer in high Al-content AlGaN QWs leads to valence subbands rearrangement, which in turn results in large optical gain for mid- and deep-UV lasers.

Journal ArticleDOI
TL;DR: In this paper, the development of AlGaN-based deep ultraviolet light emitting diodes (UV-LEDs) by molecular beam epitaxy was reported, and the maximum external quantum efficiency was 0.4%.
Abstract: We report the development of AlGaN based deep ultraviolet light emitting diodes (UV-LEDs) by molecular beam epitaxy. By growing the AlGaN well layer under Ga-rich conditions to produce strong potential fluctuations, internal quantum efficiency of a quantum well structure emitting at 300 nm was found to be 32%. By combining such Ga-rich growth condition in the active region with polarization field enhanced carrier injection layers, deep UV-LEDs emitting at 273 nm were obtained with output power of 0.35 mW and 1.3 mW at 20 mA continuous wave and 100 mA pulsed drive current, respectively. The maximum external quantum efficiency was 0.4%.

Journal ArticleDOI
TL;DR: In this article, the linear and third-order nonlinear optical absorption coefficients have been calculated in GaAs/Ga1−xAlxAs inverse parabolic quantum wells (single and double) subjected to an external electric field.
Abstract: In the present theoretical study, the linear and third-order nonlinear optical absorption coefficients have been calculated in GaAs/Ga1−xAlxAs inverse parabolic quantum wells (single and double) subjected to an external electric field. Our calculations are based on the potential morphing method in the effective mass approximation. The systematic theoretical investigation contains results with all possible combinations of the involved parameters, as quantum well width, quantum barrier width, Al concentration at each well center and magnitude of the external electric field. Our results indicate that in most cases investigated, the increase of the electric field blue-shifts the peak positions of the total absorption coefficient. In all cases studied it became apparent that the incident optical intensity considerably affects the total absorption coefficient.

Journal ArticleDOI
15 Jul 2011-Science
TL;DR: The observed quantum well states in SrVO3 ultrathin films exhibit distinctive features—such as orbital-selective quantization originating from the anisotropic orbital character of the V 3d states and unusual band renormalization of the subbands near the Fermi level—that reflect complex interactions in the quantum well.
Abstract: The quantum confinement of strongly correlated electrons in artificial structures provides a platform for studying the behavior of correlated Fermi-liquid states in reduced dimensions. We report the creation and control of two-dimensional electron-liquid states in ultrathin films of SrVO3 grown on Nb:SrTiO3 substrates, which are artificial oxide structures that can be varied in thickness by single monolayers. Angle-resolved photoemission from the SrVO3/Nb:SrTiO3 samples shows metallic quantum well states that are adequately described by the well-known phase-shift quantization rule. The observed quantum well states in SrVO3 ultrathin films exhibit distinctive features—such as orbital-selective quantization originating from the anisotropic orbital character of the V 3d states and unusual band renormalization of the subbands near the Fermi level—that reflect complex interactions in the quantum well.

Journal ArticleDOI
TL;DR: A simple technique is reported that allows obtaining mid-infrared absorption spectra with nanoscale spatial resolution under low-power illumination from tunable quantum cascade lasers.
Abstract: We report a simple technique that allows obtaining mid-infrared absorption spectra with nanoscale spatial resolution under low-power illumination from tunable quantum cascade lasers. Light absorption is detected by measuring associated sample thermal expansion with an atomic force microscope. To detect minute thermal expansion we tune the repetition frequency of laser pulses in resonance with the mechanical frequency of the atomic force microscope cantilever. Spatial resolution of better than 50 nm is experimentally demonstrated.

Journal ArticleDOI
Abstract: Using time-resolved photoluminescence spectroscopy on GaInN/GaN multiple quantum well structures, we analyze the radiative and nonradiative processes contributing to the “green gap” in GaN-based light emitting devices. We observe that it is only partly caused by a reduced oscillator strength due to the Quantum Confined Stark Effect (QCSE) which becomes stronger with increasing indium concentration and well width. As the dominant effect we observe a reduction of nonradiative lifetimes when the indium concentration is increased. For higher indium concentrations, we find an additional nonradiative recombination path that might be attributed to an increased generation of defects like misfit dislocations, nitrogen vacancies and/or indium clusters within the optically active region. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Journal ArticleDOI
TL;DR: In this article, a vertical-cavity surface-emitting laser (VCSEL) with GaAs/AlGaAs quantum wells (QWs) was fabricated and the lasing properties of the VCSEL under optical spin injection were characterized.
Abstract: We fabricated a (110)-oriented vertical-cavity surface-emitting laser (VCSEL) with GaAs/AlGaAs quantum wells (QWs) and characterized the lasing properties of the VCSEL under optical spin injection. We demonstrated circularly polarized lasing at a high degree of circular polarization of 0.96 for our VCSEL at room temperature that originated from a long electron spin relaxation time of 0.7 ns in the (110) GaAs QWs despite a really small initial electron spin polarization of 0.04, which was well reproduced by using a rate equation analysis.

Book
05 Jan 2011
TL;DR: In this article, the authors present an overview of the history of high-power laser systems and their application in industry and defense, focusing on the use of high power laser systems in thin-disk geometry.
Abstract: Part 1: Gas, Chemical, and Free-Electron Lasers 1. Carbon Dioxide Lasers 2. Excimer Lasers 3. Chemical Lasers 4. High-Power Free-Electron Lasers Part 2: Diode Lasers 5. Diode Lasers 6. High-Power Diode Laser Arrays Part 3: Solid-State Lasers 7. Introduction to High-Power Solid-State Lasers 8. Zigzag Slab Lasers 9. Nd:YAG Ceramic ThinZag High-Power Laser 10. Thin-Disc Lasers 11. Heat-Capacity Lasers 12. Ultrafast Solid-State Lasers 13. Ultrafast Lasers in Thin-Disk Geometry 14. The National Ignition Facility Laser Part 4: Fiber Lasers 15. Introduction to Optical Fiber Lasers 16. Pulsed Fiber Lasers 17. High-Power Ultrafast Fiber Laser Systems 18. High-Power Fiber Lasers for Industry and Defense Part 5: Beam Combining 19. Beam Combining Index

Journal ArticleDOI
TL;DR: Experimental observations show the marked differences in the pulse shapes while theoretical considerations reveal the underlying mechanism responsible for the contrast, identifying the increased stability of quantum-dot lasers to perturbations as the root.
Abstract: Excitability is a generic prediction for an optically injected semiconductor laser. However, the details of the phenomenon differ depending on the type of device in question. For quantum-well lasers very complicated multipulse trajectories can be found, while for quantum-dot lasers the situation is much simpler. Experimental observations show the marked differences in the pulse shapes while theoretical considerations reveal the underlying mechanism responsible for the contrast, identifying the increased stability of quantum-dot lasers to perturbations as the root.

Journal ArticleDOI
TL;DR: In this paper, a time-domain travelling-wave model for the simulation of passive mode-locking in quantum dot (QD) lasers is presented, where accurate expressions for the time varying QD optical susceptibility and the QD spontaneous emission noise source are introduced in the 1-D wave equations and numerically described using a set of infinite-impulse response filters.
Abstract: We present a time-domain travelling-wave model for the simulation of passive mode-locking in quantum dot (QD) lasers; accurate expressions for the time varying QD optical susceptibility and the QD spontaneous emission noise source are introduced in the 1-D wave equations and numerically described using a set of infinite-impulse response filters. The inhomogeneous broadening of the density of states of the whole QD ensemble as well as the homogeneous linewidth of each QD interband transition are properly taken into account in the model. Population dynamics in the QD, quantum well, and barrier states under both forward and reverse bias conditions are modeled via proper sets of multi-population rate equations coupled with the field propagation equations. The model is first applied to the study of gain and absorption recovery in a QD semiconductor optical amplifier under both forward and reverse bias conditions. Simulations of passive mode-locking in a two-section QD laser are then performed as a function of the bias parameters. Gain and absorption dynamics leading to the generation of mode-locking pulses is described. The onset of a trailing-edge instability at low currents is observed and fully explained in the framework of the described model.

Journal ArticleDOI
TL;DR: In this paper, the effect of doping and polarization on carrier collection for InGaN quantum well solar cells was investigated and it was shown that spontaneous and piezoelectric polarization sheet charges can inhibit carrier collection unless these charges are screened by sufficient doping.
Abstract: The effect of doping and polarization on carrier collection is investigated for InGaN quantum well solar cells. Energy band diagram simulations of actual devices indicate that spontaneous and piezoelectric polarization sheet charges can inhibit carrier collection unless these charges are screened by sufficient doping. By increasing the doping on both sides of the active region, the polarization-induced barriers to carrier collection were eliminated and the short circuit current density was increased from 0.1 to 1.32 mA/cm2 under 1.5 sun AM1.5G equivalent illumination, leading to devices with an open circuit voltage of 1.9 V and a fill factor of 71%.

Journal ArticleDOI
TL;DR: In this paper, the authors explain the two important reasons for the introduction of strain into the active region of a quantum-well laser, which greatly enhance almost all characteristics of semiconductor lasers and make possible a wide range of applications.
Abstract: This tutorial article explains the two important reasons for the introduction of strain into the active region of a quantum-well laser. First, it reduces the density of states at the top of the valence band, which allows population inversion to be obtained at a lower carrier density. Second, it distorts the 3-D symmetry of the crystal lattice and matches it more closely to the 1-D symmetry of the laser beam. Together these effects greatly enhance almost all characteristics of semiconductor lasers and make possible a wide range of applications. Combinations of compressive and tensile strain can also be used, for example, to produce nonabsorbing mirrors and polarization-insensitive semiconductor optical amplifiers.

Journal ArticleDOI
TL;DR: Electrically driven quantum dot, wire, and well hybrid light-emitting diodes are demonstrated by using nanometer-sized pyramid structures of GaN to show good candidates for broad-band highly efficient visible lighting sources.
Abstract: Electrically driven quantum dot, wire, and well hybrid light-emitting diodes are demonstrated by using nanometer-sized pyramid structures of GaN. InGaN quantum dots, wires, and wells are formed at the tops, edges, and sidewalls of pyramids, respectively. The hybrid light-emitting diodes containing low-dimensional quantum structures are good candidates for broad-band highly efficient visible lighting sources.

Journal ArticleDOI
TL;DR: In this article, the application of non-equilibrium Green's function formalism to the simulation of novel photovoltaic devices utilizing quantum confinement effects in low dimensional absorber structures is discussed.
Abstract: This article reviews the application of the non-equilibrium Green's function formalism to the simulation of novel photovoltaic devices utilizing quantum confinement effects in low dimensional absorber structures. It covers well-known aspects of the fundamental NEGF theory for a system of interacting electrons, photons and phonons with relevance for the simulation of optoelectronic devices and introduces at the same time new approaches to the theoretical description of the elementary processes of photovoltaic device operation, such as photogeneration via coherent excitonic absorption, phonon-mediated indirect optical transitions or non-radiative recombination via defect states. While the description of the theoretical framework is kept as general as possible, two specific prototypical quantum photovoltaic devices, a single quantum well photodiode and a silicon-oxide based superlattice absorber, are used to illustrated the kind of unique insight that numerical simulations based on the theory are able to provide.

Journal ArticleDOI
TL;DR: In this article, N-polar III-nitride quantum-well ultraviolet light-emitting diodes are grown by plasma-assisted molecular beam epitaxy that integrate polarization-induced p-type doping by compositional grading from GaN to AlGaN along N-face.
Abstract: Nitrogen-polar III-nitride heterostructures present unexplored advantages over Ga(metal)-polar crystals for optoelectronic devices. This work reports N-polar III-nitride quantum-well ultraviolet light-emitting diodes grown by plasma-assisted molecular beam epitaxy that integrate polarization-induced p-type doping by compositional grading from GaN to AlGaN along N-face. The graded AlGaN layer simultaneously acts as an electron blocking layer while facilitating smooth injection of holes into the active region, while the built-in electric field in the barriers improves carrier injection into quantum wells. The enhanced doping, carrier injection, and light extraction indicate that N-polar structures have the potential to exceed the performance of metal-polar ultraviolet light-emitting diodes.

Journal ArticleDOI
TL;DR: In this article, the authors used cathodoluminescence hyperspectral imaging with high spatial resolution to investigate peak emission energies and intensities across trenchlike features and V-pits on the surface of the MQWs.
Abstract: InGaN/GaN multiple quantum wells (MQWs) have been studied by using cathodoluminescence hyperspectral imaging with high spatial resolution. Variations in peak emission energies and intensities across trenchlike features and V-pits on the surface of the MQWs are investigated. The MQW emission from the region inside trenchlike features is redshifted by approximately 45 meV and more intense than the surrounding planar regions of the sample, whereas emission from the V-pits is blueshifted by about 20 meV and relatively weaker. By employing this technique to the studied nanostructures it is possible to investigate energy and intensity shifts on a 10 nm length scale.

Journal ArticleDOI
TL;DR: In this article, a single-junction strain-balanced quantum well solar cell (SB-QWSC) has achieved an efficiency of 28.3% in the presence of radiative recombination.
Abstract: The band gap of the quantum well (QW) solar cell can be adapted to the incident spectral conditions by tailoring the QW depth. The single-junction strain-balanced quantum well solar cell (SB-QWSC) has achieved an efficiency of 28.3%. The dominant loss mechanism at the high concentrator cell operating bias is due to radiative recombination, so a major route to further efficiency improvement requires a restriction of the optical losses. It has been found that (100) biaxial compressive strain suppresses a mode of radiative recombination in the plane of the QWs. As biaxial strain can only be engineered into a solar cell on the nanoscale, SB-QWSCs are seen to have a fundamental efficiency advantage over equivalent bulk cells. Strain-balanced quantum wells in multi-junction solar cells can current match the sub-cells without the introduction of dislocations. Calculations are shown which predict efficiency limits as a function of QW absorption and band gap for such cells. A dual-junction InGaP/GaAs solar cell with QWs in the bottom sub-cell has been grown and characterized. Laboratory and calculated efficiencies relative to control cells are presented for the reported cell and a modeled device, respectively. Copyright © 2011 John Wiley & Sons, Ltd.

Journal ArticleDOI
TL;DR: In this article, a photonic crystal slab (PCS) was used to enhance the absorption efficiency by increasing the photon lifetime in the detector active region, and the authors presented a quantum well infrared photodetector (QWIP) with 100x less quantum well doping compared to a standard QWIP.
Abstract: In this letter we present a quantum well infrared photodetector (QWIP), which is fabricated as a photonic crystal slab (PCS). With the PCS it is possible to enhance the absorption efficiency by increasing photon lifetime in the detector active region. To understand the optical properties of the device we simulate the PCS photonic band structure, which differs significantly from a real two-dimensional photonic crystal. By fabricating a PCS-QWIP with 100x less quantum well doping, compared to a standard QWIP, we are able to see strong absorption enhancement and sharp resonance peaks up to temperatures of 170 K.