Center for Quantum Devices - Most Downloaded Journal Articles

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13.	Antimonide-Based Type II Superlattices: A Superior Candidate for the Third Generation of Infrared Imaging Systems M. Razeghi, A. Haddadi, A.M. Hoang, G. Chen, S. Bogdanov, S.R. Darvish, F. Callewaert, P.R. Bijjam, and R. McClintock Journal of ELECTRONIC MATERIALS, Vol. 43, No. 8, 2014-- August 1, 2014 ...[Visit Journal] Type II superlattices (T2SLs), a system of interacting multiquantum wells,were introduced by Nobel Laureate L. Esaki in the 1970s. Since then, this material system has drawn a lot of attention, especially for infrared detection and imaging. In recent years, the T2SL material system has experienced incredible improvements in material growth quality, device structure design, and device fabrication techniques that have elevated the performance of T2SL-based photodetectors and focal-plane arrays (FPAs) to a level comparable to state-of-the-art material systems for infrared detection and imaging, such as mercury cadmium telluride compounds. We present the current status of T2SL-based photodetectors and FPAs for imaging in different infrared regimes, from short wavelength to very long wavelength, and dual-band infrared detection and imaging, as well as the future outlook for this material system. [reprint (PDF)]
13.	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)]
13.	High magnetic field studies of the two‐dimensional electron gas in GaInAs‐InP superlattices J. C. Portal; R. J. Nicholas; M. A. Brummell; M. Razeghi; M. A. Poisson J. C. Portal, R. J. Nicholas, M. A. Brummell, M. Razeghi, M. A. Poisson; High magnetic field studies of the two‐dimensional electron gas in GaInAs‐InP superlattices. Appl. Phys. Lett. 1 August 1983; 43 (3): 293–295.-- August 1, 1983 ...[Visit Journal] We report the observation of Shubnikov–de Haas oscillations in superlattices of GaInAs and InP, showing evidence of two‐dimensional behavior. The electron g‐factor is deduced from both the criteria for resolution of a spin splitting by comparison with the broadening parameter Γ, and from the tilted field method, and is shown to increase with increasing resolution of the Landau levels in a manner consistent with the theory of Ando and Uemura. In the ultraquantum limit, structure at ν=1/2 and ν=1/3 is observed. [reprint (PDF)]
13.	Quantum dot in a well infrared photodetectors for high operating temperature focal plane arrays S. Tsao, T. Yamanaka, S. Abdollahi Pour, I-K Park, B. Movaghar and M. Razeghi SPIE Proceedings, San Jose, CA Volume 7234-0V-- January 25, 2009 ...[Visit Journal] InAs quantum dots embedded in InGaAs quantum wells with InAlAs barriers on InP substrate grown by metalorganic chemical vapor deposition are utilized for high operating temperature detectors and focal plane arrays in the middle wavelength infrared. This dot-well combination is unique because the small band offset between the InAs dots and the InGaAs well leads to weak dot confinement of carriers. As a result, the device behavior differs significantly from that in the more common dot systems that have stronger confinement. Here, we present energy level modeling of our QD-QW system and apply these results to interpret the detector behavior. Detectors showed high performance with D* over 10¹⁰ cm·Hz^1/2W^-1 at 150 K operating temperature and with high quantum efficiency over 50%. Focal plane arrays have been demonstrated operating at high temperature due to the low dark current observed in these devices. [reprint (PDF)]
13.	High-power, room-temperature and continuous-wave operation of distributed-feedback quantum-cascade lasers at λ = 4.8 µm J.S. Yu, S. Slivken, S.R. Darvish, A. Evans, B. Gokden and M. Razeghi Applied Physics Letters, 87 (4)-- July 25, 2005 ...[Visit Journal] The authors present high-power continuous-wave (cw) operation of distributed-feedback quantum-cascade lasers. Continuous-wave output powers of 56 mW at 25 °C and 15 mW at 40 °C are obtained. Single-mode emission near 7.8 µm with a side-mode suppression ratio of >=30 dB and a tuning range of 2.83 cm⁻¹ was obtained between 15 and 40 °C. The device exhibits no beam steering with a full width at half maximum of 27.4° at 25 °C in cw mode. [reprint (PDF)]
13.	EPR investigation of Gd3+ and Eu2+ in the α- and β-phases of lead phosphate M. RAZEGHI, J. P. BUISSON, and B. HOULIE M. RAZEGHI et al.: EPR Investigation of Gd3+ and Eu2+ in Lead Phosphate phys. stat. sol. (b) 96, 283 (1979-- September 1, 1979 ...[Visit Journal] The X-band EPR spectra of Gd3+and Eu2+diluted in Pb3(P04)2crystals are studied. Lead phos-phate exhibits a ferroelastic phase transition a t 180 “C and the EPR spectra obtained in eachphase differ from each other. The spectra are very complex because the zero field splitting hasthe same order of magnitude as the Zeeman term. The spin Hamiltonian parameters and theenergy levels are computed. “Forbidden” or “missing” transitions and line intensities can beexplained. [reprint (PDF)]
13.	Study of Au coated ZnO nanoarrays for surface enhanced Raman scattering chemical sensing Gre´gory Barbillon, Vinod E. Sandana,Christophe Humbert, Benoit Be´lier, David J. Rogers, Ferechteh H. Teherani, Philippe Bove Ryan McClintock and Manijeh Razeghid J. Mater. Chem. C, 2017, 5, 3528-- March 20, 2017 ...[Visit Journal] At present, the simultaneous attainment of good reproducibility and high enhancement factors (EF) are key challenges in the development of surface enhanced Raman scattering (SERS)substrates for improved chemical and biological sensing. SERS substrates are generally based on distributions of metallic nanoparticles/structures with different shapes and architectures which are prepared by either thermal dewetting, precipitation from colloidal suspensions1–4 or advanced (e.g. deep UV or electron beam (EBL)) lithographic techniques.5–9 Although such substrates can exhibit large Raman enhancements, the former two techniques (colloidal and thermal dewetting) give poor SERS reproducibility while deep UV and EBL are too expensive and/or complex for mass production. [reprint (PDF)]
13.	High-speed, low-noise metal-semiconductor-metal ultraviolet photodetectors based on GaN D. Walker, E. Monroy, P. Kung, J. Wu, M. Hamilton, F.J. Sanchez, J. Diaz, and M. Razeghi Applied Physics Letters 74 (5)-- February 1, 1999 ...[Visit Journal] We present the fabrication and characterization of nonintentionally doped GaN and GaN:Mg Schottky metal–semiconductor–metal (MSM) photodetectors, grown on sapphire by metalorganic chemical vapor deposition. Low-leakage, Schottky contacts were made with Pt/Au. The devices are visible blind, with an ultraviolet/green contrast of about five orders of magnitude. The response times of the MSM devices were <10 ns and about 200 ns for GaN and GaN:Mg, respectively. The noise power spectral density remains below the background level of the system (10−24 A²/Hz) up to 5 V, for the undoped GaN MSM detector. [reprint (PDF)]
13.	Comparison of ultraviolet APDs grown on free-standing GaN and sapphire substrates E. Cicek, Z. Vashaei, C. Bayram, R. McClintock, M. Razeghi and M. Ulmer Proceedings, Vol. 7780, p. 77801P, SPIE Optics and Photonics Symposium, Conference on Detectors and Imaging Devices: Infrared, Focal Plane and Single Photon, San Diego, CA -- August 4, 2010 ...[Visit Journal] There is a need for semiconductor-based ultraviolet photodetectors to support avalanche gain in order to realize better performance andmore effective compete with existing technologies. Wide bandgap III-Nitride semiconductors are the promising material system for the development of avalanche photodiodes (APDs) that could be a viable alternative to current bulky UV detectors such as photomultiplier tubes. In this paper, we review the current state-of-the-art in IIINitride visible-blind APDs, and present our latest results on GaN APDs grown on both conventional sapphire and low dislocation density free-standing c- and m-plane GaN substrates. Leakage current, gain, and single photon detection efficiency (SPDE) of these APDs were compared. The spectral response and Geiger-mode photon counting performance of UV APDs are studied under low photon fluxes, with single photon detection capabilities as much as 30% being demonstrated in smaller devices. Geiger-mode operation conditions are optimized for enhanced SPDE. [reprint (PDF)]
13.	Self-assembled semiconductor quantum dot infrared photodetector operating at room temperature and focal plane array Ho-Chul Lim; Stanley Tsao; Wei Zhang; Manijen Razeghi Proc. SPIE 6542, Infrared Technology and Applications XXXIII, 65420R (May 14, 2007)-- May 14, 2007 ...[Visit Journal] Self-assembled semiconductor quantum dots have attracted much attention because of their novel properties and thus possible practical applications including the lasers, detectors and modulators. Especially the photodetectors which have quantum dots in their active region have been developed and show promising performances such as high operation temperature due to three dimensional confinement of the carriers and normal incidence in contrast to the case of quantum well detectors which require special optical coupling schemes. Here we report our recent results for mid-wavelength infrared quantum dot infrared photodetector grown by low-pressure metalorganic chemical vapor deposition. The material system we have investigated consists of 25 period self-assembled InAs quantum dot layers on InAlAs barriers, which are lattice-matched to InP substrates, covered with InGaAs quantum well layers and InAlAs barriers. This active region was sandwiched by highly doped InP contact layers. The device operates at 4.1 μm with a peak detectivity of 2.8×10¹¹ cm·Hz^1/2/W at 120 K and a quantum efficiency of 35 %. The photoresponse can be observed even at room temperature resulting in a peak detectivity of 6×10⁷ cm·Hz^1/2/W. A 320×256 focal plane array has been fabricated in this kind of device. Its performance will also be discussed here. [reprint (PDF)]
13.	Capacitance-voltage investigation of high purity InAs/GaSb superlattice photodiodes A. Hood, D. Hoffman, Y. Wei, F. Fuchs, and M. Razeghi Applied Physics Letters 88 (6)-- February 6, 2006 ...[Visit Journal] The residual carrier backgrounds of binary type-II InAs/GaSb superlattice photodiodes with cutoff wavelengths around 5 μm have been studied in the temperature range between 20 and 200 K. By applying a capacitance-voltage measurement technique, a residual background concentration below 10¹⁵ cm^–3 has been found. [reprint (PDF)]
13.	Low-threshold distributed feedback lasers fabricated on material grown completely by LP-MOCVD M. Razeghi; R. Blondeau; M. Krakowski; J.-C. Bouley; M. Papuchon; B. Cremoux; J. Duchemin IEEE Journal of Quantum Electronics ( Volume: 21, Issue: 6, June 1985)-- June 30, 1985 ...[Visit Journal] GaInAsP-InP distributed feedback (DFB) lasers emitting at 1.57 μm have been fabricated on material grown completely by low-pressure metalorganic chemical vapor deposition (LP-MOCVD). The CW threshold current of 60 mA and an output power of 6 mW per facet at room temperature have been obtained. The lasing wavelength λLunder CW operation showed a temperature coefficient (d_{\lambdaL}/dT) of 0.9 Å/°C for this DFB laser over the range of10-90\degC. A stable single longitudinal mode was maintained under high speed pulse modulation up to 500 ps, and sinusoidal modulation at 1 Ghz. [reprint (PDF)]
13.	MOCVD Growth of ZnO Nanostructures Using Au Droplets as Catalysts V.E. Sandana, D.J. Rogers, F.H. Teherani, R. McClintock, M. Razeghi, H.J. Drouhin, M.C. Clochard, V. Sallett, G. Garry and F. Fayoud SPIE Conference, January 20-25, 2008, San Jose, CA Proceedings – Zinc Oxide Materials and Devices III, Vol. 6895, p. 68950Z-1-6.-- February 1, 2008 ...[Visit Journal] ZnO nanostructures were synthesised by Metal Organic Chemical Vapor Deposition growth on Si (100) and c-Al₂O₃ substrates coated with a 5nm thick layer of Au. The Au coated substrates were annealed in air prior to deposition of ZnO so as to promote formation of Au nanodroplets. The development of the nanodroplets was studied as a function of annealing duration and temperature. Under optimised conditions, a relatively homogeneous distribution of regular Au nanodroplets was obtained. Using the Au nanodroplets as a catalyst, MOCVD growth of ZnO nanostructures was studied. Scanning electron microscopy revealed nanostructures with various forms including commonly observed structures such as nanorods, nanoneedles and nanotubes. Some novel nanostructures were also observed, however, which resembled twist pastries and bevelled-multifaceted table legs. [reprint (PDF)]
13.	Growth and Optimization of GaInAsP/InP Material System for Quantum Well Infrared Photodetector Applications M. Erdtmann, J. Jiang, A. Matlis, A. Tahraoui, C. Jelen, M. Razeghi, and G. Brown SPIE Conference, San Jose, CA, -- January 26, 2000 ...[Visit Journal] Multi-quantum well structures of Ga_xIn_1-xAs_yP_1-y were grown by metalorganic chemical vapor deposition for the fabrication of quantum well IR photodetectors. The thickness and composition of the wells was determined by high-resolution x-ray diffraction and photoluminescence experiments. The intersubband absorption spectrum of the Ga_0.47In_0.53As/InP, Ga_0.38In_0.62As_0.80P_0.20 (1.55 μm)/InP, and Ga_0.27In_0.73As_0.57P_0.43 (1.3 μm))/InP quantum wells are found to have cutoff wavelengths of 9.3 μm, 10.7 micrometers , and 14.2 μm respectively. These wavelengths are consistent with a conduction band offset to bandgap ratio of approximately 0.32. Facet coupled illumination responsivity and detectivity are reported for each composition. [reprint (PDF)]
13.	A review of the growth, doping, and applications of β-Ga₂O₃ thin films Manijeh Razeghi, Ji-Hyeon Park , Ryan McClintock, Dimitris Pavlidis, Ferechteh H. Teherani, David J. Rogers, Brenden A. Magill, Giti A. Khodaparast, Yaobin Xu, Jinsong Wu, Vinayak P. Dravid Proc. SPIE 10533, Oxide-based Materials and Devices IX, 105330R -- March 14, 2018 ...[Visit Journal] β-Ga₂O₃ is emerging as an interesting wide band gap semiconductor for solar blind photo detectors (SBPD) and high power field effect transistors (FET) because of its outstanding material properties including an extremely wide bandgap (Eg ~4.9eV) and a high breakdown field (8 MV/cm). This review summarizes recent trends and progress in the growth/doping of β-Ga₂O₃ thin films and then offers an overview of the state-of-the-art in SBPD and FET devices. The present challenges for β-Ga₂O₃ devices to penetrate the market in real-world applications are also considered, along with paths for future work. [reprint (PDF)]
13.	Growth of InAsSb Alloys on GaAs and Si Substrates for Uncooled Infrared Photodetector Applications J.D. Kim, H. Mohseni, J.S. Wojkowski, J.J. Lee and M. Razeghi SPIE Conference, San Jose, CA, -- January 27, 1999 ...[Visit Journal] In this paper, we report on the growth and characterization of InAsSb alloys on GaAs and Si substrates for uncooled infrared photodetector applications. The fabrication and characterization of photodetectors from the grown layers are also reported. The photovoltaic and photoconductive devices were grown on (100) GaAs and Si substrates, respectively, using molecular beam epitaxy (MBE). The composition of InAs>sub>1-xSb_x layers was 0.95 in both cases and cut-off wavelength of 7-8 μm has been obtained. At 300 K, the photovoltaic detectors on GaAs substrates resulted in a sharp cut-off wavelength of 7.5 μm with a peak responsivity as high as 0.32 V/W at 6.5 micrometer. For the photoconductive detectors on Si substrates, cut-off wavelength of 8 μm has been observed with a responsivity of 6.3x10^-2 V/W at 7 μm under an electric field of 420 V/m. [reprint (PDF)]
13.	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)]
13.	Tunability of intersubband absorption from 4.5 to 5.3 µm in a GaN/Al_0.2Ga_0.8N superlattices grown by metalorganic chemical vapor deposition N. Péré-Laperne, C. Bayram, L. Nguyen-Thê, R. McClintock, and M. Razeghi Applied Physics Letters, Vol. 95, No. 13, p. 131109-- September 28, 2009 ...[Visit Journal] Intersubband (ISB) absorption at wavelengths as long as 5.3 µm is realized in GaN/Al_0.2Ga_0.8N superlattices grown by metalorganic chemical vapor deposition. By employing low aluminum content Al_0.2Ga_0.8N barriers and varying the well width from 2.6 to 5.1 nm, ISB absorption has been tuned from 4.5 to 5.3 µm. Theoretical ISB absorption and interband emission models are developed and compared to the experimental results. The effects of band offsets and the piezoelectric fields on these superlattices are investigated. [reprint (PDF)]
13.	Responsivity and Noise Performance of InGaAs/InP Quantum Well Infrared Photodetectors C. Jelen, S. Slivken, T. David, G. Brown, and M. Razeghi SPIE Conference, San Jose, CA, -- January 28, 1998 ...[Visit Journal] Dark current nose measurements were carried out between 10 and 104 Hz at T = 80K on two InGaAs/InP quantum well IR photo detectors (QWIPs) designed for 8 μm IR detection. Using the measured noise data, we have calculated the thermal generation rate, bias-dependent gain, electron trapping probability, and electron diffusion length. The calculated thermal generation rate is similar to AlGaAs/GaAs QWIPs with similar peak wavelengths, but the gain is 50X larger, indicating improved transport and carrier lifetime are obtained in the binary InP barriers. As a result, a large responsivity of 7.5 A/W at 5V bias and detectivity of 5 X 10¹¹ cm·Hz^½/W at 1.2 V bias were measured for the InGaAs/InP QWIPs at T = 80K. [reprint (PDF)]
13.	Finite-Size Scaling in the Dissipative Transport Regime Between Quantum Hall Plateaus Razeghi M., S. Koch, R.J. Hang, K.V. Klitzing, K. Ploog Koch, S., Haug, R.J., v. Klitzing, K., Ploog, K., Razeghi, M. (1992). Finite-Size Scaling in the Dissipative Transport Regime Between Quantum Hall Plateaus. In: Bauer, G., Kuchar, F., Heinrich, H. (eds) Low-Dimensional Electronic Systems. Springer Series in Solid-State Sciences, vol 111. Springer, Berlin, Heidelberg.-- January 1, 1993 ...[Visit Journal] The magnetoresistance of a two-dimensional electron gas shows a novel scaling behaviour in the dissipative transport regime between adjacent integer quantum Hall plateaus when studied in samples of different size. At low temperatures (≥ 25mK) the phase coherence length L in may exceed the size W of small samples (W ≥ 8µm). Under these conditions the width ΔB of the magnetic field region where dissipative transport is observed becomes independent of temperature. Then ΔB only depends on the size of the sample and increases with decreasing size. Thus the critical exponent v of the localization length ξ ∝ (ΔB)−v can be determined directly. The resulting exponent v = 2.3±0.1 does not depend on the specific sample and, furthermore, is independent of the (spin-resolved) Landau level. This experimental result agrees with the predictions of several theoretical approaches to the metal-insulator transition in the quantum Hall regime. The effect described occurs both in Hall bars and in Corbino geometries, with essentially identical results. On the other hand, in a Landau level where spin-splitting is not resolved, a considerably larger value of v = 6.5 ± 0.6 is observed for the localization length exponent. [reprint (PDF)]
13.	Uncooled InAs-GaSb type-II infrared detectors grown on GaAs substrates for the 8-12-μm atmospheric window H. Mohseni, J. Wojkowski, M. Razeghi, G. Brown, and W. Mitchel IEEE J Quantum Elect 35, 1041–1044 (1999)-- July 1, 1999 ...[Visit Journal] We report on the growth and characterization of type-II infrared detectors with an InAs-GaSb superlattice active layer for the 8-12-mu m atmospheric window at 300 K, The material was grown by molecular beam epitaxy on semi-insulating GaAs substrates. Photoconductive detectors fabricated from the superlattices showed 80% cutoff at about 12 mu m at room temperature. The responsivity of the device is about 2 mA/W with a 1-V bias (E = 5 V/cm) and the maximum measured detectivity of the device is 1.3 x 10(8) cm.Hz(1/2)/W at 11 mu m at room temperature. The detector shows very weak temperature sensitivity. Also, the extracted effective carrier lifetime, tau = 26 ns, is an order of magnitude longer than the carrier lifetime in HgCdTe with similar bandgap and carrier concentration. [reprint (PDF)]
13.	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 Applied Physics Letters 81 (5)-- July 29, 2002 ...[Visit Journal] We demonstrate light emission at 280 nm from UV light-emitting diodes consisting of AlInGaN/AlInGaN multiple quantum wells. Turn-on voltage of the devices is ~5 V with a differential resistance of ~40 Ω. The peak emission wavelength redshifts ~1 nm at high injection currents. [reprint (PDF)]
13.	Photoluminescence study of InAsSb/InAsSbP heterostructures grown by low-pressure metalorganic chemical vapor deposition S. Kim, M. Erdtmann, D. Wu, E. Kaas, H. Yi, J. Diaz, and M. Razeghi Applied Physics Letters 69 (11)-- September 9, 1996 ...[Visit Journal] Photoluminescence has been measured for double‐ and separate‐confinement InAsSb/InAsSbP heterostructures grown by low‐pressure metalorganic vapor deposition. A measurement of the integrated luminescence intensity at the temperature range of 77–300 K shows that over a wide range of excitation level (1–5×10² W/cm²) the radiative transitions are the dominant. mechanism below T∼170 K. Auger recombination coefficient C=C₀ exp(−E_a/kT) with C₀≊5×10⁻²⁷ cm⁶/s and E_a≊40 meV has been estimated. [reprint (PDF)]
13.	Current status and potential of high power mid-infrared intersubband lasers S. Slivken, Y. Bai, B. Gokden, S.R. Darvish and M. Razeghi SPIE Proceedings, San Francisco, CA (January 22-28, 2010), Vol. 7608, p. 76080B-1-- January 22, 2010 ...[Visit Journal] Some of the recent advances in high power quantum cascade laser development will be reviewed in this paper. Research areas explored include short wavelength (λ <4 µm) lasers, high performance strain-balanced heterostructures, and high power long wavelength (7< λ< 16 µm) lasers. Near λ=4.5 µm, highlights include demonstration of 18% continuous wave wallplug efficiency at room temperature, 53% pulsed wallplug efficiency at 40 K, and 120 W of peak power output from a single device at room temperature. Near λ ~10 µm, up to 0.6 W of continuous output power at room temperature has also been demonstrated, with pulsed efficiencies up to 9%. [reprint (PDF)]
13.	Effects of well width and growth temperature on optical and structural characteristics of AlN/GaN superlattices grown by metal-organic chemical vapor deposition C. Bayram, N. Pere-Laperne, and M. Razeghi Applied Physics Letters, Vol. 95, No. 20, p. 201906-1-- November 16, 2009 ...[Visit Journal] AlN/GaN superlattices (SLs) employing various well widths (from 1.5 to 7.0 nm) are grown by metal-organic chemical vapor deposition technique at various growth temperatures (Ts) (from 900 to 1035 °C). The photoluminescence (PL), x-ray diffraction, and intersubband (ISB) absorption characteristics of these SLs and their dependency on well width and growth temperature are investigated. Superlattices with thinner wells (grown at the same Ts) or grown at lower Ts (employing the same well width) are shown to demonstrate higher strain effects leading to a higher PL energy and ISB absorption energy. Simulations are employed to explain the experimental observations. ISB absorptions from 1.04 to 2.15 µm are demonstrated via controlling well width and growth temperature. [reprint (PDF)]

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