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16 Jan 1995

Volume 66, Issue 3, pp. 253-395

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Temperature dependence of threshold current density Jth and differential efficiency ηd of high‐power InGaAsP/GaAs (λ=0.8 μm) lasers

H. J. Yi, J. Diaz, I. Eliashevich, M. Stanton, M. Erdtmann, X. He, L. J. Wang, and M. Razeghi

Appl. Phys. Lett. 66, 253 (1995); http://dx.doi.org/10.1063/1.114193 (3 pages) | Cited 11 times

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An experimental and theoretical study on temperature dependence of the threshold current density Jth and differential efficiency ηd for the InGaAsP/GaAs laser diodes emitting at λ=0.8 μm was performed. Threshold current density Jth increases and differential efficiency ηd decreases as temperature is increased mainly because of thermal broadening of the gain spectrum. However, the measured temperature dependence of Jth and ηd could not be explained when only this effect was considered. In this letter, the temperature dependence of momentum relaxation rate ℏ/τ of carriers was investigated by performing the photoluminescence study. At high temperature, increase of the momentum relaxation rate ℏ/τ leads to reduction of the gain and mobility and increase of the optical loss, causing higher Jth and lower ηd as experimentally observed. The resulting theoretical model provides a good explanation for the mechanism of the increase of Jth and decrease of ηd. © 1995 American Institute of Physics.
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42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings

Bifunctional chromophore for photorefractive applications

Yue Zhang, Saswati Ghosal, Martin K. Casstevens, and Ryszard Burzynski

Appl. Phys. Lett. 66, 256 (1995); http://dx.doi.org/10.1063/1.114194 (3 pages) | Cited 12 times

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A bifunctional chromophore has been developed which serves as a charge transporting agent as well as a second‐order nonlinear optical compound. The chromophore has been incorporated into an inert polymer to form a photorefractive material when doped with a photocharge generation sensitizer. The dependence of the four‐wave mixing diffraction efficiency, holographic grating writing rate, and two‐beam coupling gain on the chromophore concentration has been studied. The results confirm the photorefractive character of the composite. © 1995 American Institute of Physics.
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42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
42.70.Jk Polymers and organics
78.66.Qn Polymers; organic compounds

Possibility of off‐resonance lasing in vertical cavity surface emitting lasers

Leonard F. Register, Rich Baca, Gregory A. Kosinovsky, Matt Grupen, and Karl Hess

Appl. Phys. Lett. 66, 259 (1995); http://dx.doi.org/10.1063/1.114195 (3 pages) | Cited 1 time

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Light emission from vertical cavity surface emitting lasers (VCSELs) is modeled as directed radiation away from a localized source within the VCSEL optical cavity into an open system as a continuous function of frequency, analogous to antenna radiation, but with field sources provided by spontaneous emission and gain. To allow near‐analytical solution, a quasi‐one‐dimensional system is analyzed. This approach reproduces the familiar threshold condition, mode gain times lifetime equals unity, at the cavity quasimode frequency; however, it also predicts that lasing is not restricted to the quasimode frequency. © 1995 American Institute of Physics.
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42.55.Px Semiconductor lasers; laser diodes
42.60.-v Laser optical systems: design and operation

Two‐channel surface‐normal wavelength division demultiplexer using substrate guided waves in conjunction with multiplexed waveguide holograms

Maggie M. Li and Ray T. Chen

Appl. Phys. Lett. 66, 262 (1995); http://dx.doi.org/10.1063/1.114196 (3 pages) | Cited 3 times

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We report a wavelength division demultiplexer (WDDM) using collinear surface‐normal input and output coupling. The reported device employs polymer‐based multiplexed waveguide holograms in conjunction with substrate guided waves. A two‐channel WDDM device operating at 700 and 738 nm with diffraction angles of 45° and 50° are demonstrated. The peak diffraction efficiencies of 80% and 77% are measured for these two channels. A crosstalk of −31 dB between the two channels is measured. Variations of the diffraction efficiencies and of the bandwidths as a function of film thickness and index modulation are further considered. A good agreement between theoretical analysis and experimental results is obtained. © 1995 American Institute of Physics.
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42.79.Sz Optical communication systems, multiplexers, and demultiplexers

Tunable mid‐infrared generation by difference frequency mixing of diode laser wavelengths in intersubband InGaAs/AlAs quantum wells

H. C. Chui, G. L. Woods, M. M. Fejer, E. L. Martinet, and J. S. Harris

Appl. Phys. Lett. 66, 265 (1995); http://dx.doi.org/10.1063/1.113512 (3 pages) | Cited 14 times

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We demonstrate difference frequency generation (DFG) of 8.66–11.34 μm wavelength light in intersubband InGaAs/AlAs quantum wells by mixing of 1.92 μm±25 nm and 2.39 μm±39 nm. The peak DFG second order nonlinear susceptibility χ(2) is measured to be 12±1 nm/V, more than 65 times that of GaAs, at a difference frequency output wavelength of 9.50 μm. The intersubband absorption for the 1–2 and 1–3 transitions is measured to be 9.3 and 2.1 μm, respectively. Second harmonic generation (SHG) of 4.76, 5.12, and 5.36 μm light with a CO2 laser is observed with a peak SHG χ(2) of 52±3 nm/V. Good agreement of experiment with theory is found for both the linear and nonlinear optical properties. This demonstration of mid‐infrared DFG opens the possibility for monolithic diode laser pumps and compact waveguide frequency converters as tunable midinfrared sources. © 1995 American Institute of Physics.
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42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
78.66.Fd III-V semiconductors

Blue‐violet light emitting gallium nitride p‐n junctions grown by electron cyclotron resonance‐assisted molecular beam epitaxy

R. J. Molnar, R. Singh, and T. D. Moustakas

Appl. Phys. Lett. 66, 268 (1995); http://dx.doi.org/10.1063/1.113513 (3 pages) | Cited 93 times

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Blue‐violet gallium nitride (GaN) light emitting p‐n junctions were grown by the method of electron cyclotron resonance‐assisted molecular beam epitaxy. This method has been modified to minimize plasma induced defects. Contrary to similar devices grown by metalorganic chemical vapor deposition, these devices do not require any postgrowth annealing to activate the Mg acceptors in the p layer. These devices turn‐on at approximately 3 V and have a spectral emission peaking at 430 nm. © 1995 American Institute of Physics.  
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85.60.Jb Light-emitting devices
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
78.60.Fi Electroluminescence

Three‐wave mixing susceptibility of carrier injected AlGaAs asymmetric quantum wells for mid‐infrared difference‐frequency generation

V. W. Lee and T. K. Gustafson

Appl. Phys. Lett. 66, 271 (1995); http://dx.doi.org/10.1063/1.113514 (3 pages) | Cited 6 times

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We calculate the three‐wave mixing susceptibility of an asymmetric AlGaAs quantum well for difference‐frequency generation of mid‐infrared radiation. The effects of carrier injection and input field strength on the interband mixing process are considered. A peak susceptibility more than two orders of magnitude larger than that of bulk GaAs is obtained. Based on these results, the possibility of difference‐frequency mixing within a semiconductor quantum well laser is discussed.
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42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
78.66.Fd III-V semiconductors

Low‐loss strain induced optical waveguides in strontium barium niobate (Sr0.6Ba0.4Nb2O6) at 1.3 μm wavelength

J. M. Marx, Z. Tang, O. Eknoyan, H. F. Taylor, and R. R. Neurgaonkar

Appl. Phys. Lett. 66, 274 (1995); http://dx.doi.org/10.1063/1.113515 (3 pages) | Cited 16 times

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Low‐loss optical waveguides have been produced in z‐cut Sr0.6Ba0.4Nb2O6 (SBN:60) and electro‐optic modulation has been demonstrated at a wavelength of 1.3 μm. The refractive index increase responsible for waveguiding results from a strain produced by a SiO2 film which has been deposited on the surface of the substrate at 320 °C. The waveguides are formed in the crystal by dry etching of channels in the strain film. The resulting optical waveguides support both polarizations. Propagation loss values of 0.7 dB/cm for TM polarization and 1.6 dB/cm for TE polarization were measured. Electro‐optic modulation up to 22 MHz was performed on repoled samples using coplanar electrodes. © 1995 American Institute of Physics.
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42.79.Gn Optical waveguides and couplers

Linewidth and α‐factor in AlGaAs/GaAs vertical cavity surface emitting lasers

D. Kuksenkov, S. Feld, C. Wilmsen, H. Temkin, S. Swirhun, and R. Leibenguth

Appl. Phys. Lett. 66, 277 (1995); http://dx.doi.org/10.1063/1.113516 (3 pages) | Cited 17 times

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Measurements of the α‐factor, the linewidth‐power product, and the differential gain in AlGaAs/GaAs vertical cavity surface emitting lasers are presented. The linewidth power product of 95 MHz mW which results in the α‐factor of 3.7 is obtained. The α‐factor as a ratio of the refractive index and gain derivatives with respect to the carrier density is also estimated. From the small signal modulation measurements of the resonance frequency, a differential gain of 3.7×1016 cm2 is obtained. The estimate of differential effective index is made difficult by an anomalously strong dependence of the emission wavelength on injection current. © 1995 American Institute of Physics.
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42.55.Px Semiconductor lasers; laser diodes
42.60.-v Laser optical systems: design and operation

New doped lithium niobate crystal with high resistance to photorefraction—LiNbO3:In

Yongfa Kong, Jinke Wen, and Huafu Wang

Appl. Phys. Lett. 66, 280 (1995); http://dx.doi.org/10.1063/1.113517 (2 pages) | Cited 54 times

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Highly indium‐doped lithium niobate crystals have been grown. It was found that a LiNbO3:In (5 mol %) crystal had a similar high resistance to photorefraction as a LiNbO3:Zn (7.5 mol %) crystal. The result of x‐ray fluorescence showed that the doped concentration of In in LiNbO3:In (5 mol % in the melt) exceeds the concentration threshold of trivalant elements (3.0 mol % in the crystal). The LiNbO3:In (5 mol %) crystal is another doped LiNbO3 crystal with high resistance to light‐induced refractive index damage. © 1995 American Institute of Physics.
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42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials
42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation

Submicron, soft x‐ray fluorescence imaging

Bruno La Fontaine, Alastair A. MacDowell, Zhengquan Tan, Don L. White, Gary N. Taylor, Obert R. Wood, John E. Bjorkholm, Don M. Tennant, and Steven L. Hulbert

Appl. Phys. Lett. 66, 282 (1995); http://dx.doi.org/10.1063/1.113518 (3 pages)

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Submicron fluorescence imaging of soft x‐ray aerial images, using a high resolution fluorescent crystal is reported. Features as small as 0.1 μm were observed using a commercially available single‐crystal phosphor, STI‐F10G (Star Tech Instruments Inc. P. O. Box 2536, Danbury, CT 06813‐2536), excited with 139 Å light. Its quantum efficiency was estimated to be 5–10 times that of sodium salicylate and to be constant over a broad spectral range from 30 to 400 Å. A comparison with a terbium‐activated yttrium orthosilicate fluorescent crystal is also presented. Several applications, such as the characterization of the aerial images produced by deep ultraviolet or extreme ultraviolet lithographic exposure tools, are envisaged. © 1995 American Institute of Physics.
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07.60.Pb Conventional optical microscopes
07.85.-m X- and γ-ray instruments
42.70.Gi Light-sensitive materials

Photomixing up to 3.8 THz in low‐temperature‐grown GaAs

E. R. Brown, K. A. McIntosh, K. B. Nichols, and C. L. Dennis

Appl. Phys. Lett. 66, 285 (1995); http://dx.doi.org/10.1063/1.113519 (3 pages) | Cited 129 times

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Low‐temperature‐grown (LTG) GaAs is used as an optical‐heterodyne converter or photomixer, to generate coherent continuous‐wave output radiation from microwave frequencies up to 3.8 THz. The photomixer consists of an epitaxial layer of LTG GaAs with interdigitated electrodes fabricated on the top surface. Terahertz photocurrents are generated in the gaps between the electrodes, and power is radiated into free space through a three‐turn self‐complementary spiral antenna. In a photomixer having a 0.27‐ps electron‐hole lifetime and small electrode capacitance, the output power is practically flat up to about 300 GHz and then rolls off at a rate of approximately 12 dB/oct. © 1995 American Institute of Physics.
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42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
84.30.Ng Oscillators, pulse generators, and function generators
85.60.-q Optoelectronic devices
72.20.Ht High-field and nonlinear effects

Laser cavity mirror imperfections and reflectivity: A time‐dependent numerical approach

Igor Vurgaftman and Jasprit Singh

Appl. Phys. Lett. 66, 288 (1995); http://dx.doi.org/10.1063/1.113520 (3 pages) | Cited 1 time

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While the cleaving process used for semiconductor Fabry–Pérot lasers produces atomically abrupt mirrors, there is considerable interest in mirrors defined by etching. Depending on the etching process employed, disorder of varying nature and degree results at the semiconductor–air interface. A theoretical approach capable of quantifying the impact of such disorder on the mirror reflectivity, to which laser performance is intimately connected, is presented. The theoretical technique is time‐dependent to facilitate visualization of the scattering process and is based on a locally one‐dimensional implicit‐finite‐difference approximation to the two‐dimensional scalar wave equation with variable coefficients. Mirror disorder is described in terms of a feature depth parameter and an in‐plane correlation length. The reflectivity falls off exponentially with disorder yet is found to remain close to its unperturbed value for the disorder scale attainable with the state‐of‐the‐art etching technology. © 1995 American Institute of Physics.  
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42.55.Px Semiconductor lasers; laser diodes
81.65.-b Surface treatments

Growth and transducer properties of an acoustic superlattice with its periods varying gradually

Shi‐de Cheng, Yong‐yuan Zhu, Ya‐lin Lu, and Nai‐ben Ming

Appl. Phys. Lett. 66, 291 (1995); http://dx.doi.org/10.1063/1.113521 (2 pages) | Cited 14 times

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Acoustic superlattices with periods varying gradually are grown by the Czochralski method. The transducer made of the acoustic superlattice is fabricated. The insertion loss measurement shows the transducer has a wide frequency response range. © 1995 American Institute of Physics.
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68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
43.38.Fx Piezoelectric and ferroelectric transducers

Epitaxial regrowth of ruby on sapphire for an integrated thin film stress sensor

Q. Wen, D. R. Clarke, Ning Yu, and M. Nastasi

Appl. Phys. Lett. 66, 293 (1995); http://dx.doi.org/10.1063/1.113522 (3 pages) | Cited 15 times

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The formation of thin film ruby by the epitaxial growth of Cr‐doped amorphous alumina on sapphire is described. The incorporation of Cr onto the Al cation sites has been found by ion channeling measurements. It is also confirmed by the observation of the R1 and R2 luminescence lines characteristic of ruby. The frequency of the R lines shift linearly with applied stress and the piezo‐spectroscopic coefficient is the same as for bulk ruby. © 1995 American Institute of Physics.
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81.15.Np Solid phase epitaxy; growth from solid phases
78.55.Hx Other solid inorganic materials
68.60.Bs Mechanical and acoustical properties

The role of the substrate in photoenhanced metalorganic chemical vapor deposition

E. Maayan, O. Kreinin, D. Veinger, A. Thon, G. Bahir, and J. Salzman

Appl. Phys. Lett. 66, 296 (1995); http://dx.doi.org/10.1063/1.113523 (3 pages) | Cited 1 time

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A GaAs laser diode has been used as the light source for the selective epitaxial growth of GaAs by photoenhanced metalorganic chemical vapor deposition (PE‐MOCVD). The use of GaAs/InGaP layered structures as substrates for these experiments permitted to accurately control the availability of photoexcited carriers reaching the GaAs growth surface. The experimental results obtained rule out pure pyrolysis and photolysis as possible mechanisms responsible for the PE growth rate, and indicate that photoexcited carriers are directly involved in the PE process. The experimental data are consistent with a kinetic model that invokes surface recombination as the main physical mechanism for the PE growth rate effect. © 1995 American Institute of Physics.
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68.55.-a Thin film structure and morphology
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Ferroelectric/(La,Sr)2CuO4 epitaxial heterostructure with high thermal stability

Yukio Watanabe, M. Tanamura, Y. Matsumoto, H. Asami, and A. Kato

Appl. Phys. Lett. 66, 299 (1995); http://dx.doi.org/10.1063/1.113524 (3 pages) | Cited 13 times

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Three‐dimensionally aligned epitaxial (Pb,La)(Zr,Ti)O3/(La,Sr)2CuO4 multilayers were grown on SrTiO3 (100) single crystals by pulse laser deposition. A cube‐on‐cube epitaxial relationship of these multilayers was confirmed by the θ‐2θ diffraction profile and the pole figure. The stability of their interfaces was confirmed by depth profiles and x‐ray diffractometry of the as‐deposited and the annealed multilayers having 100–300‐Å‐thick (La,Sr)2CuO4 layers. The results suggest that the multilayers can be applied to the ferroelectric field‐effect transistor. © 1995 American Institute of Physics.
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68.55.-a Thin film structure and morphology
81.15.Fg Pulsed laser ablation deposition
77.55.-g Dielectric thin films

Room temperature electron cyclotron resonance chemical vapor deposition of high quality TiN

Mohamed Boumerzoug, Zhengda Pang, Marcel Boudreau, Peter Mascher, and John G. Simmons

Appl. Phys. Lett. 66, 302 (1995); http://dx.doi.org/10.1063/1.113525 (3 pages) | Cited 8 times

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High quality, gold‐colored TiN was deposited at room temperature by decomposing TiCl4 in the downstream of an N2/H2 electron cyclotron resonance (ECR) plasma. The morphology of the as‐deposited films was investigated by scanning electron microscopy, and the resistivity was measured using the four point probe technique. The films were uniform over 2 in. wafers, with resistivities of 100–150 μΩ cm. Auger electron spectroscopy was used for the determination of the Ti/N ratio and for the detection of contaminants, and shows that the as‐deposited films were stoichiometric and chlorine free. The present results represent a major improvement in lowering the deposition temperature of TiN using ECR plasma‐enhanced chemical vapor deposition with TiCl4 as reactant. © 1995 American Institute of Physics.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.55.-a Thin film structure and morphology
73.61.-r Electrical properties of specific thin films

Fabrication of multilayer single‐electron tunneling devices

E. H. Visscher, S. M. Verbrugh, J. Lindeman, P. Hadley, and J. E. Mooij

Appl. Phys. Lett. 66, 305 (1995); http://dx.doi.org/10.1063/1.113526 (3 pages) | Cited 36 times

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A reliable process has been developed for the fabrication of multilevel single‐electron tunneling (SET) devices. Using this process, we have fabricated SET devices with Au‐SiO‐Al and Al‐AlOx‐SiO‐Al overlap capacitors. The SET transistors exhibit voltage gain and, despite the complex device structure, have a low charge noise (7×10−5e/√Hz). Moreover, the use of overlap capacitors in SET devices results in a reduction of cross capacitances down to 8%. © 1995 American Institute of Physics.
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85.40.Hp Lithography, masks and pattern transfer
85.30.Tv Field effect devices

Phase transformation of cobalt induced by ball milling

J. Y. Huang, Y. K. Wu, and H. Q. Ye

Appl. Phys. Lett. 66, 308 (1995); http://dx.doi.org/10.1063/1.113527 (3 pages) | Cited 38 times

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We have found that phase transformation can occur in cobalt when subjected to ball milling. The two modifications of cobalt, i.e., face‐center‐cubic (fcc) and hexagonal close‐packed (hcp) phases, which usually coexist at room temperature and are often difficult to be separated from each other, can now be easily separated by using the simple ball milling technique. The phase formation of cobalt was found to depend on the mill intensity. Under different mill intensity or different milling time, the phase transformations follow the routes of hcp+fcc→hcp, hcp+fcc→hcp→fcc+hcp, and hcp+fcc→hcp→fcc+hcp→fcc, respectively. Our results indicate that the phase formation of cobalt induced by ball milling was determined by the accumulation of structure defects. Different mill intensity may adjust the rate and level of the accumulation of defects. © 1995 American Institute of Physics.
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61.66.Bi Elemental solids
64.70.K- Solid-solid transitions
81.30.Kf Martensitic transformations

Ultrahigh nucleation density for growth of smooth diamond films

G. S. Yang and M. Aslam

Appl. Phys. Lett. 66, 311 (1995); http://dx.doi.org/10.1063/1.113528 (3 pages) | Cited 19 times

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An ultrahigh density seeding process of diamond thin‐film deposition is demonstrated. Diamond powders with average grain sizes of 0.038 and 0.101 μm were used to study the surface roughness as a function of deposition time, film thickness, and nucleation density. The diamond films, prepared by hot filament chemical vapor deposition, were characterized by atomic force microscopy, scanning electron microscopy, and Raman spectroscopy. An extremely high nucleation density on the order of 1011 cm−2 was achieved by coating 0.038 μm diamond powder on the surface of the Si substrate. One micron thick films were obtained with the mean surface roughness of 30 nm. © 1995 American Institute of Physics.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Metallization of poly(4‐methyl‐1‐pentene) microcellular foam

W. Lee Perry, Robert C. Dye, Paul G. Apen, Larry Foreman, and Eric Peterson

Appl. Phys. Lett. 66, 314 (1995); http://dx.doi.org/10.1063/1.113529 (3 pages) | Cited 4 times

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Low density microcellular foam from poly(4‐methyl‐1‐pentene) (PMP) has been metallized by laser‐induced chemical vapor deposition (LICVD). KrF excimer laser radiation (248 nm) was used to photolytically decompose molybdenum hexacarbonyl with and without a buffer gas. Metal oxycarbide deposits 100 μm in diameter were formed. The microstructure of the PMP foam was unaltered. The deposition was confirmed to be 100 μm using scanning electron microscopy and energy dispersive x‐ray spectroscopy. X‐ray fluorescence was used to determine that approximately 80 ng of material was deposited. © 1995 American Institute of Physics.  
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
82.70.Rr Aerosols and foams

High temperature surface peaks and surface reconstruction of the (001) SrTiO3−δ substrate surfaces studied by channeling

C. C. Chin and T. Morishita

Appl. Phys. Lett. 66, 317 (1995); http://dx.doi.org/10.1063/1.113530 (3 pages)

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The temperature dependence of the surface peaks of the (001) SrTiO3 substrate surfaces was studied for the sample temperature up to 750 °C by channeling. The temperature dependence of the Sr surface peaks was found to be due to the thermal vibration of the Sr atoms. However, an anomalous temperature dependence of the Ti surface peak was observed which may be due to the displacement of Ti surface atoms. The Ti surface peaks are maximum at 400 °C. For the reduced SrTiO3−δ, surface reconstruction was observed on the Sr surface sublattice but the anomalous temperature dependence of the Ti surface peak disappeared. © 1995 American Institute of Physics.
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68.35.-p Solid surfaces and solid-solid interfaces: structure and energetics

Size evolution of low energy electron generated Ca colloids in CaF2

R. Bennewitz, C. Günther, M. Reichling, E. Matthias, S. Vijayalakshmi, A. V. Barnes, and N. H. Tolk

Appl. Phys. Lett. 66, 320 (1995); http://dx.doi.org/10.1063/1.113531 (3 pages) | Cited 14 times

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Metal colloids in CaF2 created by low energy electron irradiation are identified by their optical absorption bands. A mean colloid radius of 18 nm is deduced from a narrow colloid band found in crystals irradiated at room temperature. Absorption data reveal a strong influence of crystal temperature during irradiation on metallization efficiency, mean colloid size, and colloid size distribution. A reversible absorption band shift is observed when turning the electron beam on and off, which may indicate a decrease of colloid size during electron irradiation. © 1995 American Institute of Physics.
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61.80.Fe Electron and positron radiation effects
61.72.J- Point defects and defect clusters
78.30.Hv Other nonmetallic inorganics
78.40.Ha Other nonmetallic inorganics

High field transport in an edge overgrown lateral superlattice

Ç. Kurdak, A. Zaslavsky, D. C. Tsui, M. B. Santos, and M. Shayegan

Appl. Phys. Lett. 66, 323 (1995); http://dx.doi.org/10.1063/1.113532 (3 pages) | Cited 7 times

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We have realized by cleaved edge overgrowth a two‐dimensional electron gas system in a one‐dimensional lateral superlattice consisting of 100 periods of 120 Å GaAs/20 Å AlGaAs. These devices exhibit nonlinear I–V, including negative differential resistance, at high electric fields. We demonstrate, by monitoring the changes in the two‐dimensional electron density, that the nonlinear I–V is due to high field induced electron trapping. © 1995 American Institute of Physics.
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73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
73.50.Fq High-field and nonlinear effects
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