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16.  MOCVD grown β-Ga2O3 metal-oxide-semiconductor field effect transistors on sapphire
Ji-Hyeon Park , Ryan McClintock, Alexandre Jaud, Arash Dehzangi , Manijeh Razeghi
Applied Physics Express 12, 095503-- August 28, 2019 ...[Visit Journal]
We fabricated β-Ga2O3:Si metal-oxide field-effect transistors (MOSFETs) on c-plane sapphire substrates which typically showed maximum drain current of 100 mA·mm−1. β-Ga2O3:Si thin films were realized on c-plane sapphire substrates through a combination of metalorganic chemical vapor deposition and post-annealing. The MOSFET device presented excellent on/off drain current ratio of ∼1011 with very low gate leakage current, sharp pinch off behavior, and a breakdown voltage of 400 V at VG = −40 V. The growth and fabrication of β-Ga2O3:Si MOSFETs on c-plane sapphire is valuable to its demonstration of the great potential for future high-power electronic devices. [reprint (PDF)]
 
16.  Quantum-Cascade Lasers Operating in Continuous-Wave Mode Above 90°C at λ ~5.25 µm
A. Evans, J. Nguyen, S. Slivken, J.S. Yu, S.R. Darvish, and M. Razeghi
Applied Physics Letters 88 (5)-- January 30, 2006 ...[Visit Journal]
We report on the design and fabrication of λ~5.25 μm quantum-cascade lasers (QCLs) for very high temperature continuous-wave (CW) operation. CW operation is reported up to a maximum temperature of 90 °C (363 K). CW output power is reported in excess of 500 mW near room temperature with a low threshold current density. A finite element thermal model is used to investigate the Gth and maximum CW operating temperature of the QCLs. [reprint (PDF)]
 
16.  Overview of Antimonide Based III-V Semiconductor Epitaxial Layers and their Applications at the Center for Quantum Devices
M. Razeghi
The European Physical Journal-Applied Physics, Vol. 23-- September 15, 2003 ...[Visit Journal]
The properties of Sb-based III-V semiconductor compounds for optoelectronic applications in the mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) range were reviewed. The growths of the Sb-based binary, ternary and quaternary were studied by molecular beam epitaxy (MBE) and metalorganic chemical vapor deposition (MOCVD). The structural, optical and electrical characterizations were carried out. Focal plane array, photoconductors and photodiodes were fabricated for the MWIR and LWIR range. Doublehetero structure (DH), multi-quantum well (MQW) and strained superlattice (SSL) lasers in the 3-5 μm range were fabricated. InAs-GaSb type-II superlattices were designed, grown and fabricated into photodetectors for the MWIR and LWIR range. [reprint (PDF)]
 
16.  Demonstration of a 256x256 Middle-Wavelength Infrared Focal Plane Array based on InGaAs/InGaP Quantum Dot Infrared Photodetectors (QDIPs)
J. Jiang, K. Mi, S. Tsao, W. Zhang, H. Lim, T.O'Sullivan, T. Sills, M. Razeghi, G.J. Brown, and M.Z. Tidrow
Applied Physics Letters, 84 (13)-- April 29, 2004 ...[Visit Journal]
We report a demonstration of an infrared focal plane array based on InGaAs/InGaP quantum dot infrared photodetectors. The middle-wavelength infrared quantum-dot infrared photodetector (QDIP) structure was grown via low-pressure metal organic chemical vapor deposition. A detectivity of 3.6×1010 cm·Hz½/W was achieved at T = 95 K and a bias of –1.4 V. The background limited temperature of our QDIP was 140 K with a 45° field of view. A 256×256 detector array was fabricated with dry etching, and hybridized to a Litton readout chip by indium bumps. Thermal imaging was achieved at temperatures up to 120 K. At T = 77 K, the noise equivalent temperature difference was measured as 0.509 K with a 300 K background and f/2.3 optics. [reprint (PDF)]
 
16.  Top-emission ultraviolet light-emitting diodes with peak emission at 280 nm
A. Yasan, R. McClintock, K. Mayes, S.R. Darvish, P. Kung, and M. Razeghi
Virtual Journal of Nanoscale Science & Technology, 5-- August 5, 2002 ...[Visit Journal][reprint (PDF)]
 
16.  Improved performance of quantum cascade lasers via manufacturable quality epitaxial side down mounting process utilizing aluminum nitride heatsinks
A. Tsekoun, R. Go, M. Pushkarsky, M. Razeghi, C.K.N. Patel
SPIE Conference, San Jose, CA, Vol. 6127, pp. 612702-- January 23, 2006 ...[Visit Journal]
We report substantially improved performance of high power quantum cascade lasers by utilizing epi-side down mounting that provides superior heat dissipation properties. We have obtained CW power output of 450 mW at 20°C from mid-IR QCLs. The improved thermal management achieved with epi-side down mounting has also permitted us to carry out initial lifetime tests on the mid-IR QCLs. No degradation of power output is seen even after over 300 hours of CW operation at 25°C with power output in excess of 300 mW. We believe these improvements should permit incorporation of mid-IR QCLs in reliable instrumentation. [reprint (PDF)]
 
16.  Infrared detection from GaInAs/InP nanopillar arrays
A. Gin, B. Movaghar, M. Razeghi and G.J. Brown
Nanotechnology 16-- July 1, 2005 ...[Visit Journal]
We report on the photoresponse from large arrays of 40 nm radius nanopillars with sensitivity in the long-wavelength infrared regime. Using photoluminescence techniques, a peak wavelength blue shift of approximately 5 meV was observed at 30 K from GaInAs/InP nanopillar structures, indicating carrier confinement effects. Responsivity measurements at 30 K indicated peak wavelength response at about 8 µm with responsivity of 420 mA/W at −2 V bias. We have also measured the noise and estimated the peak detectivity to be 3×108 cm·Hz½·W−1 at 1 V reverse bias and 30 K. A maximum internal quantum efficiency of 4.5% was derived from experiment. Both the photo and the dark transport have been successfully modeled as processes that involve direct and indirect field-assisted tunneling as well as thermionic emission. The best agreement with experiment was obtained when allowances were made for the non-uniformity of barrier widths and electric field heating of carriers above the lattice temperature. [reprint (PDF)]
 
16.  Sharp/Tuneable UVC Selectivity and Extreme Solar Blindness in Nominally Undoped Ga2O3 MSM Photodetectors Grown by Pulsed Laser Deposition
D. J. Rogers, A. Courtois, F. H. Teherani, V. E. Sandana, P. Bove, X. Arrateig, L. Damé, P. Maso, M. Meftah, W. El Huni, Y. Sama, H. Bouhnane, S. Gautier, A. Ougazzaden, M. Razeghi
Proc. SPIE 11687, Oxide-based Materials and Devices XII, 116872D (24 March 2021); doi: 10.1117/12.2596194 ...[Visit Journal]
Ga2O3 layers were grown on c-sapphire substrates by pulsed laser deposition. Optical transmission spectra were coherent with a bandgap engineering from 4.9 to 6.2 eV controlled via the growth conditions. X-ray diffraction revealed that the films were mainly β-Ga2O3 (monoclinic) with strong (-201) orientation. Metal-Semiconductor-Metal photodetectors based on gold/nickel Inter- Digitated-Transducer structures were fabricated by single-step negative photolithography. 240 nm peak response sensors gave over 2 orders-of-magnitude of separation between dark and light signal with state-of-the-art solar and visible rejection ratios ((I240 : I290) of > 3 x 105 and (I240 : I400) of > 2 x 106) and dark signals of <50 pA (at a bias of -5V). Spectral responsivities showed an exceptionally narrow linewidth (16.5 nm) and peak values exhibited a slightly superlinear increase with applied bias up to a value of 6.5 A/W (i.e. a quantum efficiency of > 3000%) at 20V bias. [reprint (PDF)]
 
16.  Pulsed metalorganic chemical vapor deposition of high quality AlN/GaN superlattices for intersubband transitions
C. Bayram, B. Fain, N. Pere-Laperne, R. McClintock and M. Razeghi
SPIE Proceedings, San Jose, CA Volume 7222-12-- January 26, 2009 ...[Visit Journal]
A pulsed metalorganic chemical vapor deposition (MOCVD) technique, specifically designed for high quality AlN/GaN superlattices (SLs) is introduced. Optical quality and precise controllability over layer thicknesses are investigated. Indium is shown to improve interface and surface quality. An AlN/GaN SL designed for intersubband transition at a telecommunication wavelength of ~1.5 µm, is grown, and processed for intersubband (ISB) absorption measurements. Room temperature measurements show intersubband absorption centered at 1.49 µm. Minimal (n-type) silicon doping of the well is shown to be crucial for good ISB absorption characteristics. The potential to extend this technology into the far infrared and even the terahertz (THz) region is also discussed. [reprint (PDF)]
 
16.  Electrically pumped photonic crystal distributed feedback quantum cascade lasers
Y. Bai, S.R. Darvish, S. Slivken, P. Sung, J. Nguyen, A. Evans, W. Zhang, and M. Razeghi
Applied Physics Letters, Vol. 91, No. 14, p. 141123-1-- October 1, 2007 ...[Visit Journal]
We demonstrate electrically pumped, room temperature, single mode operation of photonic crystal distributed feedback (PCDFB) quantum cascade lasers emitting at ~4.75 µm. Ridge waveguides of 100 µm width were fabricated with both PCDFB and Fabry-Pérot feedback mechanisms. The Fabry-Pérot device has a broad emitting spectrum and a double lobed far-field character. The PCDFB device, as expected, has primarily a single spectral mode and a diffraction limited far field characteristic with a full angular width at half maximum of 2.4°. This accomplishment represents the first step in power scaling of single mode, midinfrared laser diodes operating at room temperature. [reprint (PDF)]
 
16.  Mid-infrared quantum cascade lasers with high wall plug efficiency
Y. Bai, B. Gokden, S. Slivken, S.R. Darvish, S.A. Pour, and M. Razeghi
SPIE Proceedings, San Jose, CA Volume 7222-0O-- January 26, 2009 ...[Visit Journal]
We demonstrate optimization of continuous wave (cw) operation of 4.6 µm quantum cascade lasers (QCLs). A 19.7 µm by 5 mm, double channel processed device exhibits 33% cw WPE at 80 K. Room temperature cw WPE as high as 12.5% is obtained from a 10.6 µm by 4.8 mm device, epilayer-down bonded on a diamond submount. With the semi-insulating regrowth in a buried ridge geometry, 15% WPE is obtained with 2.8 W total output power in cw mode at room temperature. This accomplishment is achieved by systematically decreasing the parasitic voltage drop, reducing the waveguide loss and improving the thermal management. [reprint (PDF)]
 
16.  High-Power CW Mid-IR Quantum Cascade Lasers
J.R. Meyer, W.W. Bewley, J.R. Lindle, I. Vurgaftman, A.J. Evans, J.S. Yu, S. Slivken, and M. Razeghi
SPIE Conference, Jose, CA, -- January 22, 2005 ...[Visit Journal]
We report the cw operation of quantum cascade lasers that do not require cryogenic cooling and emit at λ = 4.7-6.2 µm. At 200 K, more than 1 W of output power is obtained from 12-µm-wide stripes, with a wall-plug efficiency (ηwall) near 10%. Room-temperature cw operation has also been demonstrated, with a maximum output power of 640 mW (ηwall = 4.5%) at 6 µm and 260 mW (ηwall = 2.3%) at 4.8 µm. Far-field characterization indicates that whereas the beam quality remains close to the diffraction limit in all of the tested lasers, in the devices emitting at 6.2 µm the beam tends to steer by as much as 5-10° degrees in either direction with varying temperature and pump current. [reprint (PDF)]
 
16.  Minority electron unipolar photodetectors based on Type-II InAs/GaSb/AlSb superlattices for very long wavelength infrared detection
B.M. Nguyen, S. Bogdanov, S. Abdollahi Pour, and M. Razeghi
Applied Physics Letters, Vol. 95, No. 18, p. 183502-- November 2, 2009 ...[Visit Journal]
We present a hybrid photodetector design that inherits the advantages of traditional photoconductive and photovoltaic devices. The structure consists of a barrier layer blocking the transport of majority holes in a p-type semiconductor, resulting in an electrical transport due to minority carriers with low current density. By using the M-structure superlattice as a barrier region, the band alignments can be experimentally controlled, allowing for the efficient extraction of the photosignal with less than 50 mV bias. At 77 K, a 14 µm cutoff detector exhibits a dark current 3.3 mA·cm−2, a photoresponsivity of 1.4 A/W, and the associated shot noise detectivity of 4×1010 Jones. [reprint (PDF)]
 
16.  Electroluminescence of InAs/GaSb heterodiodes
D. Hoffman, A. Hood, E. Michel, F. Fuchs, and M. Razeghi
IEEE Journal of Quantum Electronics, 42 (2)-- February 1, 2006 ...[Visit Journal]
The electroluminescence of a Type-II InAs-GaSb superlattice heterodiode has been studied as a function of injection current and temperature in the spectral range between 3 and 13 μm. The heterodiode comprises a Be-doped midwavelength infrared (MWIR) superlattice with an effective bandgap around 270 meV and an undoped long wavelength infrared (LWIR) superlattice with an effective bandgap of 115 meV. [reprint (PDF)]
 
16.  A detailed analysis of carrier transport in InAs0.3Sb0.7 layers grown on GaAs substrates by metalorganic chemical vapor deposition
C. Besikci, Y.H. Choi, G. Labeyrie, E. Bigan and M. Razeghi with J.B. Cohen, J. Carsello, and V.P. Dravid
Journal of Applied Physics 76 (10)-- November 15, 1994 ...[Visit Journal]
InAs0.3Sb0.7 layers with mirrorlike morphology have been grown on GaAs substrates by low‐pressure metalorganic chemical vapor deposition. A room‐temperature electron Hall mobility of 2×104 cm²/V· s has been obtained for a 2 μm thick layer. Low‐temperature resistivity of the layers depended on TMIn flow rate and layer thickness. Hall mobility decreased monotonically with decreasing temperature below 300 K. A 77 K conductivity profile has shown an anomalous increase in the sample conductivity with decreasing thickness except in the near vicinity of the heterointerface. In order to interpret the experimental data, the effects of different scattering mechanisms on carrier mobility have been calculated, and the influences of the lattice mismatch and surface conduction on the Hall measurements have been investigated by applying a three‐layer Hall‐effect model. Experimental and theoretical results suggest that the combined effects of the dislocations generated by the large lattice mismatch and strong surface inversion may lead to deceptive Hall measurements by reflecting typical n‐type behavior for a p‐type sample, and the measured carrier concentration may considerably be affected by the surface conduction up to near room temperature. A quantitative analysis of dislocation scattering has shown significant degradation in electron mobility for dislocation densities above 107 cm−2. The effects of dislocation scattering on hole mobility have been found to be less severe. It has also been observed that there is a critical epilayer thickness (∼1 μm) below which the surface electron mobility is limited by dislocation scattering. [reprint (PDF)]
 
16.  Bias–selectable nBn dual–band long–/very long–wavelength infrared photodetectors based on InAs/InAsSb/AlAsSb type–II superlattices
Abbas Haddadi, Arash Dehzangi, Romain Chevallier, Sourav Adhikary, & Manijeh Razeghi
Nature Scientific Reports 7, Article number: 3379-- June 13, 2017 ...[Visit Journal]
Type–II superlattices (T2SLs) are a class of artificial semiconductors that have demonstrated themselves as a viable candidate to compete with the state–of–the–art mercury–cadmium–telluride material system in the field of infrared detection and imaging. Within type–II superlattices, InAs/InAs1−xSbx T2SLs have been shown to have a significantly longer minority carrier lifetime. However, demonstration of high–performance dual–band photodetectors based on InAs/InAs1−xSbx T2SLs in the long and very long wavelength infrared (LWIR & VLWIR) regimes remains challenging. We report the demonstration of high–performance bias–selectable dual–band long–wavelength infrared photodetectors based on new InAs/InAsSb/AlAsSb type–II superlattice design. Our design uses two different bandgap absorption regions separated by an electron barrier that blocks the transport of majority carriers to reduce the dark current density of the device. As the applied bias is varied, the device exhibits well–defined cut–off wavelengths of either ∼8.7 or ∼12.5 μm at 77 K. This bias–selectable dual–band photodetector is compact, with no moving parts, and will open new opportunities for multi–spectral LWIR and VLWIR imaging and detection. [reprint (PDF)]
 
16.  Growth of “moth-eye” ZnO nanostructures on Si(111), c-Al2O3, ZnO and steel substrates by pulsed laser deposition
Vinod E. Sandana, David J. Rogers, Ferechteh Hosseini Teherani, Philippe Bove, Michael Molinari, Michel Troyon, Alain Largeteau, Gérard Demazeau, Colin Scott, Gaelle Orsal, Henri-Jean Drouhin, Abdallah Ougazzaden, Manijeh Razeghi
Phys. Status Solidi C., 1-5 (2013)-- August 6, 2013 ...[Visit Journal]
Self-forming, vertically-aligned, arrays of black-body-like ZnO moth-eye nanostructures were grown on Si(111), c-Al2O3, ZnO and high manganese austenitic steel substrates using Pulsed Laser Deposition. X-ray diffraction (XRD) revealed the nanostructures to be well-crystallised wurtzite ZnO with strong preferential c-axis crystallographic orientation along the growth direction for all the substrates. Cathodoluminescence (CL) studies revealed emission characteristic of the ZnO near band edge for all substrates. Such moth-eye nanostructures have a graded effective refractive index and exhibit black-body characteristics. Coatings with these features may offer improvements in photovoltaic and LED performance. Moreover, since ZnO nanostructures can be grown readily on a wide range of substrates it is suggested that such an approach could facilitate growth of GaN-based devices on mismatched and/or technologically important substrates, which may have been inaccessible till present. [reprint (PDF)]
 
16.  Demonstration of Planar Type-II Superlattice-Based Photodetectors Using Silicon Ion-Implantation
Arash Dehzangi, Donghai Wu, Ryan McClintock, Jiakai Li, Alexander Jaud and Manijeh Razeghi
Photonics 2020, 7(3), 68; https://doi.org/10.3390/photonics7030068-- September 3, 2020 ...[Visit Journal]
In this letter, we report the demonstration of a pBn planar mid-wavelength infrared photodetectors based on type-II InAs/InAs1−xSbx superlattices, using silicon ion-implantation to isolate the devices. At 77 K the photodetectors exhibited peak responsivity of 0.76 A/W at 3.8 µm, corresponding to a quantum efficiency, without anti-reflection coating, of 21.5% under an applied bias of +40 mV with a 100% cut-off wavelength of 4.6 µm. With a dark current density of 5.21 × 10−6 A/cm2, under +40 mV applied bias and at 77 K, the photodetector exhibited a specific detectivity of 4.95 × 1011 cm·Hz1/2/W. [reprint (PDF)]
 
16.  High power photonic crystal distributed feedback quantum cascade lasers emitting at 4.5 micron
B. Gokden, S. Slivken and M. Razeghi
SPIE Proceedings, San Francisco, CA (January 22-28, 2010), Vol. 7608, p. 760806-1-- January 22, 2010 ...[Visit Journal]
Quantum cascade lasers possess very small linewidth enhancement factor, which makes them very prominent candidates for realization of high power, nearly diffraction limited and single mode photonic crystal distributed feedback broad area lasers in the mid-infrared frequencies. In this paper, we present room temperature operation of a two dimensional photonic crystal distributed feedback quantum cascade laser emitting at 4.5 µm. peak power up to ~0.9 W per facet is obtained from a 2 mm long laser with 100 µm cavity width at room temperature. The observed spectrum is single mode with a very narrow linewidth. Far-field profile has nearly diffraction limited single lobe with full width at half maximum of 3.5 degree normal to the facet. The mode selection and power output relationships are experimentally established with respect to different cavity lengths for photonic crystal distributed feedback quantum cascade lasers. [reprint (PDF)]
 
16.  On the Description of the Collision Terms in Three-Valley Hydrodynamic Models for GaAs Device Modeling
C. Besikci and M. Razeghi
IEEE Transactions on Electron Devices 41 (8)-- August 1, 1994 ...[Visit Journal]
A reduced set of transport parameters is proposed for the collision terms of the three-valley hydrodynamic model which is a faster alternative to ensemble Monte Carlo simulations. The predictions of the proposed model have been found to be in excellent agreement with transient ensemble Monte Carlo data. The reduction in the number of the transport parameters makes the model relatively easy to implement with substantial accuracy. The transport parameters which are of interest in semiclassical device modeling are presented as a function of electron energy. [reprint (PDF)]
 
16.  Persistent photoconductivity and the quantized Hall effect in In0.53Ga0.47As/InP heterostructures
H. P. Wei; D. C. Tsui; M. Razeghi
H. P. Wei, D. C. Tsui, M. Razeghi; Persistent photoconductivity and the quantized Hall effect in In0.53Ga0.47As/InP heterostructures. Appl. Phys. Lett. 15 September 1984; 45 (6): 666–668.-- September 15, 1984 ...[Visit Journal]
A persistent photoconductivity is observed in the transport of the high mobility two‐dimensional electron gas in In0.53Ga0.47 As/InP heterostructures. Low field Hall measurements from 300 to 4.2 K and the quantized Hall effect in the high field limit are studied with radiation from visible and infrared light‐emitting diodes. Our results demonstrate conclusively that the effect is due to photogeneration of electron‐hole pairs in the heterostructure and trapping of holes in the In0.53Ga0.47 As. [reprint (PDF)]
 
16.  Intersubband hole absorption in GaAs-GaInP Quantum Wells grown by Gas Source Molecular Beam Epitaxy
J. Hoff, C. Jelen, S. Slivken, E. Michel, O. Duchemin, E. Bigan, and M. Razeghi with G. Brown and S.M. Hegde (Wright Laboratory)
Applied Physics Letters 65 (9)-- August 29, 1994 ...[Visit Journal]
P-doped GaAs‐GaInP quantum wells have been grown on GaAs substrate by gas source molecular beam epitaxy. Structural quality has been evidenced by x-ray diffraction. A narrow low-temperature photoluminescence full width at half‐maximum has been measured. Strong hole intersubband absorption has been observed at 9 μm, and its dependence on light polarization has been investigated. [reprint (PDF)]
 
16.  Type-II Superlattices and Quantum Cascade Lasers for MWIR and LWIR Free-Space Communications
A. Hood, A. Evans and M. Razeghi
SPIE Conference, January 20-25, 2008, San Jose, CA Proceedings – Quantum Sensing and Nanophotonic Devices V, Vol. 6900, p. 690005-1-9.-- February 1, 2008 ...[Visit Journal]
Free-space optical communications has recently been touted as a solution to the "last mile" bottleneck of high-speed data networks providing highly secure, short to long range, and high-bandwidth connections. However, commercial near infrared systems experience atmospheric scattering losses and scintillation effects which can adversely affect a link's operating budget. By moving the operating wavelength into the mid- or long-wavelength infrared enhanced link uptimes and increased operating range can be achieved due to less susceptibility to atmospheric affects. The combination of room-temperature, continuous-wave, high-power quantum cascade lasers and high operating temperature type-II superlattice photodetectors offers the benefits of mid- and long-wavelength infrared systems as well as practical operating conditions for next generation free-space communications systems. [reprint (PDF)]
 
16.  Recent progress of widely tunable, CW THz sources based QCLs at room temperature
Manijeh Razeghi
Terahertz Science and Technology, Vol.10, No.4, pp. 87-151-- December 7, 2017 ...[Visit Journal]
The THz spectral region is of significant interest to the scientific community, but is one of the hardest regions to access with conventional technology. A wide range of compelling new applications are initiating a new revolution in THz technology, especially with regard to the development of compact and versatile devices for THz emission and detection. In this article, recent advances with regard to III-V semiconductor optoelectronics are explored with emphasis on how these advances will lead to the next generation of THz component technology [reprint (PDF)]
 
16.  Ga/sub 0.51/In/sub 0.49/P/GaAs HEMT's exhibiting good electrical performance at cryogenic temperatures
Y.-J. Chan; D. Pavlidis; M. Razeghi; F. Omnes
IEEE TRANS. ELEC.DEVICES. 77. IO. 1990-- October 1, 1990 ...[Visit Journal]
The DC and microwave characteristics of Ga/sub 0.51/In/sub 0.49/P/GaAs HEMTs grown by metalorganic chemical vapor deposition (MOCVD) are presented. Devices with 1- mu m-long gates show transconductances of 163 and 213 mS/mm at 300 and 77 K, respectively. Their maximum cutoff frequency is 17.8 GHz. Deep traps in the doped layer are evaluated at low temperature by the threshold voltage shift and current collapse phenomena. GaInP/GaAs HEMTs show no current collapse and have almost zero threshold voltage shift compared to AlGaAs/GaAs and InAlAs/InGaAs where the corresponding values are 0.5 and 0.25 V, respectively. [reprint (PDF)]
 

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