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22 Oct 1990

Volume 57, Issue 17, pp. 1709-1827

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Amplification by stimulated emission from optically pumped nickel vapor in an ultraviolet region

K. Hirata, S. Yoshino, and H. Ninomiya

Appl. Phys. Lett. 57, 1709 (1990); http://dx.doi.org/10.1063/1.104065 (3 pages) | Cited 1 time

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Amplification by stimulated emission has been observed from an optically pumped nickel vapor on the transitions at 347 and 381 nm. Nickel vapor was produced by direct laser vaporization, and the nickel atoms were optically pumped by a N2 laser at 337 nm. The amplification factor at 347 nm reaches a maximum after the amplification factor at 381 nm reaches a maximum. The maximum amplification factors are 1.62 and 1.69, respectively.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.60.By Design of specific laser systems

Destruction of a MgF2 optical coating by 250 keV α particle irradiation

Marcus H. Mendenhall and Robert A. Weller

Appl. Phys. Lett. 57, 1712 (1990); http://dx.doi.org/10.1063/1.104141 (3 pages) | Cited 1 time

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Magnesium fluoride coatings ∼170 Å thick have been evaporated onto mirror‐quality Be substrates in ultrahigh vacuum and subsequently subjected to 250 keV α particle irradiation at room temperature. Analysis of the irradiated area by medium energy backscattering spectrometry revealed that the irradiation selectively removed fluorine with an initial yield of 2.2 fluorine atoms per incident α particle. A visible degradation in reflectivity, which became progressively more extensive with increasing dose, was observed after an α particle fluence of 1016 cm−2. After a total irradiation of 4×1017 cm−2 less than 20% of the fluorine in the film remained, effectively reducing it to metallic magnesium. The effect of this change on the reflectivity of the surface was catastrophic.
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61.80.Jh Ion radiation effects
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces
81.40.Tv Optical and dielectric properties related to treatment conditions
78.66.-w Optical properties of specific thin films

Observation of multiple wavelength soliton collisions in optical systems with fiber amplifiers

P. A. Andrekson, N. A. Olsson, P. C. Becker, J. R. Simpson, T. Tanbun‐Ek, R. A. Logan, and K. W. Wecht

Appl. Phys. Lett. 57, 1715 (1990); http://dx.doi.org/10.1063/1.104044 (3 pages) | Cited 14 times

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Solitons of different wavelengths are found to exhibit substantial spectral and temporal changes when collisions are centered in erbium‐doped fiber amplifiers. By using two soliton pulse trains, with ∼70‐ps‐wide pulses, spectrally separated by 1.8 Å, and 106 km of non‐dispersion‐shifted fiber, we observe a spectral and temporal shift of as much as 0.35 Å and 55 ps, respectively, for each soliton. Both soliton wavelengths shift the same amount, but in opposite directions and remain undisturbed in terms of shape and amplitude after the collision. This shift may impose limitations on multiple wavelength soliton based communication systems utilizing fiber amplifiers.
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42.50.Md Optical transient phenomena: quantum beats, photon echo, free-induction decay, dephasings and revivals, optical nutation, and self-induced transparency
42.65.Tg Optical solitons; nonlinear guided waves
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
42.79.Sz Optical communication systems, multiplexers, and demultiplexers
42.81.Dp Propagation, scattering, and losses; solitons

Electrically tunable optical filter for infrared wavelength using liquid crystals in a Fabry–Perot étalon

J. S. Patel, M. A. Saifi, D. W. Berreman, Chinlon Lin, N. Andreadakis, and S. D. Lee

Appl. Phys. Lett. 57, 1718 (1990); http://dx.doi.org/10.1063/1.104045 (3 pages) | Cited 49 times

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Using the refractive index modulation in liquid crystals by an externally applied electric field, we show that common nematic liquid crystals can be used in a Fabry–Perot étalon to produce an electrically tunable optical filter for use in the infrared region. Using commercial liquid crystals we demonstrate that the wavelength can be tuned over 175 nm using less than 10 V. In our first device the free‐spectral range of the étalon is about 75 nm with a passband of about 1–2 nm which is determined by the quality of the mirrors that we have used.
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42.79.Ci Filters, zone plates, and polarizers
42.25.Lc Birefringence
78.20.Jq Electro-optical effects
61.30.-v Liquid crystals

Gain mechanism of the vertical‐cavity surface‐emitting semiconductor laser

D. G. Deppe

Appl. Phys. Lett. 57, 1721 (1990); http://dx.doi.org/10.1063/1.104046 (3 pages) | Cited 17 times

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The vertical‐cavity surface‐emitting single quantum well laser is examined in terms of the short Fabry–Perot cavity’s effect on optical gain. It is suggested that for this vertical‐ cavity structure the optical gain mechanism is fundamentally altered as compared to the case of the more standard edge‐emitting device with longer cavity lengths. The short cavity and highly reflecting mirrors of the vertical cavity structure lead to an enhanced gain coefficient at fixed carrier densities, due to enhanced spontaneous emission into the Fabry–Perot modes of the optical cavity, and the resultantly reduced spontaneous linewidth.
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42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.55.Px Semiconductor lasers; laser diodes

Construction of an all‐optical flip‐flop by combination of two optical triodes

Hiroyuki Tsuda and Takashi Kurokawa

Appl. Phys. Lett. 57, 1724 (1990); http://dx.doi.org/10.1063/1.104047 (3 pages) | Cited 8 times

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An optical flip‐flop with two nonlinear étalons as inverter gates was investigated. The results show that the device works well for a large coupling constant, large detuning (which lead to a high contrast and stable operation), and short feedback delay. Based on calculated results, an optical flip‐flop was constructed by coupling two optical triode switches using a nonlinear étalon and gradient‐index lenses, and successful operation was demonstrated.
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42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks
42.65.Pc Optical bistability, multistability, and switching, including local field effects

Blue and green cw upconversion lasing in Er:YLiF4

T. Hebert, R. Wannemacher, W. Lenth, and R. M. Macfarlane

Appl. Phys. Lett. 57, 1727 (1990); http://dx.doi.org/10.1063/1.104048 (3 pages) | Cited 75 times

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Two new laser transitions are reported for the Er3+ ion in YLiF4: in the blue at 469.7 nm and in the green at 560.6 nm. These are pumped with red and near‐infrared laser radiation using nonlinear excitation processes in which more than one upconversion step occurs, yet the threshold pump powers are as low as 10 mW. Single longitudinal mode cw operation was observed at temperatures below 40 K. This is the first report of a blue laser using the Er3+ ion, and the first report of an infrared‐pumped blue laser.
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42.55.Rz Doped-insulator lasers and other solid state lasers
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation

Experimental verification of an ion‐induced focus model for the recirculating electron beam injector

James W. Poukey, Michael G. Mazarakis, and R. C. Platt

Appl. Phys. Lett. 57, 1730 (1990); http://dx.doi.org/10.1063/1.104049 (3 pages)

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We present a model for the operation of a particular type of electron beam diode used in the Sandia Recirculating Linear Accelerator system. The critical element of the model is ion emission from the anode aperture, which neutralizes enough beam space charge to permit focusing. Recent experimental results are shown which support the model in several respects.
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52.59.Mv High-voltage diodes
52.75.Fk Magnetohydrodynamic generators and thermionic convertors; plasma diodes
41.75.Fr Electron and positron beams
07.77.-n Atomic, molecular, and charged-particle sources and detectors

In situ x‐ray photoelectron spectroscopy and reflection high‐energy electron diffraction study of diethylgalliumchloride adsorption on Si (100) and Si (111) surfaces

C. Sasaoka, Y. Kato, A. Usui, H. Hirayama, and T. Tatsumi

Appl. Phys. Lett. 57, 1733 (1990); http://dx.doi.org/10.1063/1.104050 (3 pages)

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Diethylgalliumchloride (DEGaCl) adsorption on Si(100) 2×1 and Si(111) 7×7 surfaces is studied by reflection high‐energy electron diffraction and x‐ray photoelectron spectroscopy. DEGaCl adsorbs molecularly on the (100) surface at room temperature, while the Ga—Cl bond dissociates on Si(111). The Si(111) 7×7 structure is greatly disturbed after DEGaCl exposure, indicating a strong interaction between the surface and the adsorbate. The spatial distribution of dangling bonds is thought to be responsible for the differences in the reactivity between the two surfaces. The Ga—ethyl bond dissociates on both Si(100) and (111) surfaces after annealing at 210 °C, and at the same time Cl desorbs from the surfaces. The Cl desorption process is also discussed.
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82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces

Tantalum as a diffusion barrier between copper and silicon

Karen Holloway and Peter M. Fryer

Appl. Phys. Lett. 57, 1736 (1990); http://dx.doi.org/10.1063/1.104051 (3 pages) | Cited 126 times

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We have investigated the effectiveness and failure mechanism of thin tantalum layers as diffusion barriers to copper. 50 nm tantalum films were sputtered onto unpatterned single‐crystal 〈100〉 Si wafers and overlaid with 100 nm Cu. Material reactions in these films were followed as a function of annealing temperature by in situ resistance measurements, and characterized by Rutherford backscattering spectroscopy and cross‐section transmission electron microscopy. While pure Cu on Si reacts at 200 °C, the Ta film prevents Cu silicon interaction up to 600 °C. At higher temperatures, reaction of the Si substrate with Ta forms a planar layer of hexagonal TaSi2. Cu rapidly penetrates to the Si substrate, forming η″‐Cu3Si precipitates at the Ta‐Si2‐Si interface.
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68.35.Fx Diffusion; interface formation
68.55.Nq Composition and phase identification
66.30.J- Diffusion of impurities

Crystallization of ultrathin W‐Si multilayer structures by high‐energy heavy ion irradiations

J. Marfaing, W. Marine, B. Vidal, M. Toulemonde, M. Hage Ali, and J. P. Stoquert

Appl. Phys. Lett. 57, 1739 (1990); http://dx.doi.org/10.1063/1.104052 (3 pages) | Cited 10 times

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Ultrathin amorphous multilayers structures (1.55 nm bilayer period) were irradiated by high‐energy heavy ion (127I and 238U ions). Transmission electron microscopy study shows that the ion‐material interaction in such a configuration leads to an irreversible transformation of the initial amorphous structures. In this letter, we report the first observation of the crystallization of the multilayers induced by the heavy ion irradiations with a subsequent formation of a new WSi structure. The crucial role of the electronic effects in the crystallization process is discussed relatively to the other phenomena induced under the ion irradiation.
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61.80.Jh Ion radiation effects
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
73.61.At Metal and metallic alloys
68.55.-a Thin film structure and morphology

Epitaxial growth of crystalline, diamond‐like films on Si (100) by laser ablation of graphite

J. A. Martin, L. Vazquez, P. Bernard, F. Comin, and S. Ferrer

Appl. Phys. Lett. 57, 1742 (1990); http://dx.doi.org/10.1063/1.104053 (3 pages) | Cited 35 times

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Pulsed laser evaporation has been used to deposit ultrathin (<1 nm) carbon films on Si (100) in an ultrahigh vacuum environment. Auger spectroscopy studies revealed a layer‐by‐layer growth up to the fourth layer. Within this coverage range, the electronic structure of the carbon atoms evolves from carbidic to diamond‐like. Above two layers the topmost one consists exclusively of carbon atoms as evidenced by low‐energy ion scattering experiments. Scanning tunneling microscopy shows that the films are crystalline and that the surface lattice is hexagonal.
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81.15.Kk Vapor phase epitaxy; growth from vapor phase
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
81.15.Jj Ion and electron beam-assisted deposition; ion plating
68.55.-a Thin film structure and morphology

Processing and properties of nanophase amorphous metallic alloys: Ni‐Ti

R. S. Averback, H. Hahn, H. J. Höfler, and J. C. Logas

Appl. Phys. Lett. 57, 1745 (1990); http://dx.doi.org/10.1063/1.104054 (3 pages) | Cited 10 times

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Amorphous Ni‐Ti alloys were synthesized by producing nanoscale amorphous Ni‐Ti particles and compacting these powders, in situ, in a high vacuum environment. X‐ray diffraction measurements revealed that crystallization occurs in these alloys in the temperature range 450–550 °C, although measurements of electrical resistivity and heat release showed that other relaxation processes occur at lower temperatures. The Vicker’s hardness of these alloys is ≊350 kg/mm2. The results are discussed in terms of interparticle or grain boundaries in the amorphous alloy.
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81.05.Bx Metals, semimetals, and alloys
46.55.+d Tribology and mechanical contacts
61.72.Mm Grain and twin boundaries
61.66.Dk Alloys

Low angle x‐ray reflection study of ultrathin Ge films on (100) Si

J.‐M. Baribeau

Appl. Phys. Lett. 57, 1748 (1990); http://dx.doi.org/10.1063/1.104055 (3 pages) | Cited 14 times

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We report a glancing incidence x‐ray reflection study of ultrathin (1–12 monolayers) Ge films grown on (100) Si by molecular beam epitaxy. Thin buried Ge layers were characterized by analyzing intensity oscillations arising from the interference of the x rays reflected at the Si/Ge interface and at the surface of a Si capping layer. Strong interference fringes were detected even for a 1‐monolayer‐thick Ge film. The intensity of the fringes was found to increase with the Ge thickness up to 6 monolayers. A damping of the fringes was observed for a thicker film, suggesting a breakdown of two‐dimensional growth. This interpretation was corroborated by a transmission electron microscopy investigation which showed evidence of three‐dimensional growth only in the 12 monolayer film.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.55.-a Thin film structure and morphology
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
78.66.-w Optical properties of specific thin films

Step‐flow growth on strained surfaces: (Al,Ga)Sb tilted superlattices

S. A. Chalmers, H. Kroemer, and A. C. Gossard

Appl. Phys. Lett. 57, 1751 (1990); http://dx.doi.org/10.1063/1.104056 (3 pages) | Cited 24 times

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We have demonstrated the molecular beam epitaxial growth of (Al,Ga)Sb tilted superlattices (TSLs) on 2° vicinal (100) GaSb and GaAs substrates. The TSLs grown on GaSb substrates exhibit good AlSb/GaSb separation and a uniform short‐range superlattice period. The TSLs grown on GaAs substrates are similar, except for the presence of threading dislocations and a decreased uniformity. The existence of TSLs proves that step‐flow growth can occur in this material system, and in the presence of strain. Lateral fluctuations in the tilt angle of the superlattice are observed and are found to be caused by a nonuniform adatom distribution which is correlated with the surface step density.
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68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.35.B- Structure of clean surfaces (and surface reconstruction)

High‐mobility CdTe films grown by molecular beam epitaxy with excess Cd

Y. S. Wu, A. Waag, and R. N. Bicknell‐Tassius

Appl. Phys. Lett. 57, 1754 (1990); http://dx.doi.org/10.1063/1.104057 (3 pages) | Cited 12 times

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We report the fact that n‐type conducting CdTe can be grown by molecular beam epitaxy (MBE) with excess Cd flux and show for the first time details of the CdTe/Cd surface phase reconstruction diagram.The surface phase diagram has been mapped over the substrate temperature range 180–375 °C using Cd/CdTe ratios between 0.0 and 1.0. At low Cd/CdTe ratios and high temperatures a (2×1) reconstruction is observed and at high Cd/CdTe flux ratios we observe a c(2×2) reconstruction. We have also observed a strong influence of substrate illumination on the surface reconstruction.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.55.Nq Composition and phase identification
68.35.B- Structure of clean surfaces (and surface reconstruction)
68.35.Dv Composition, segregation; defects and impurities

Magnetotransport in narrow In0.53Ga0.47As/InP wires

A. Menschig, A. Forchel, B. Roos, R. Germann, K. Pressel, W. Heuring, and D. Grützmacher

Appl. Phys. Lett. 57, 1757 (1990); http://dx.doi.org/10.1063/1.104058 (3 pages) | Cited 10 times

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We have fabricated dry etched In0.53Ga0.47As quantum wires with geometrical widths varying from 80 nm to 50 μm from modulation‐doped heterostructures. All wires show finite resistances even at 40 mK without illumination. The magnetotransport measurements show clearly the depopulation of one‐dimensional subbands, universal conductance fluctuations, and an anomalous magnetoresistance peak.
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73.50.Jt Galvanomagnetic and other magnetotransport effects (including thermomagnetic effects)
72.80.Ey III-V and II-VI semiconductors
73.61.Ey III-V semiconductors
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions

Using decomposed disilane as a gas source for Si epitaxial growth on Ge (111): Photoemission studies

S. Van, D. Steinmetz, F. Ringeisen, D. Bolmont, and J. J. Koulmann

Appl. Phys. Lett. 57, 1760 (1990); http://dx.doi.org/10.1063/1.104059 (3 pages) | Cited 11 times

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A good Si epitaxial growth rate on Ge (111) has been achieved at substrate temperatures as low as 350 °C thanks to the use of decomposed disilane in the catalytic chemical vapor deposition (CTL‐CVD) method. For substrate temperatures in the (100–200 °C) range, an exposure of the Ge (111) wafer to decomposed disilane led to the formation of an amorphous silicon film. The growth rate of this Si layer was found to be several times higher when using decomposed disilane rather than undecomposed disilane. At substrate temperatures above 400 °C, an interdiffusion of Si into Ge occurred in both cases of disilane and decomposed disilane exposures.
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81.15.Kk Vapor phase epitaxy; growth from vapor phase
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.65.-b Surface treatments

Boron delta doping in Si and Si0.8Ge0.2 layers

H. Jorke and H. Kibbel

Appl. Phys. Lett. 57, 1763 (1990); http://dx.doi.org/10.1063/1.104060 (3 pages) | Cited 32 times

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By using an elemental boron effusion cell, B delta doping structures (5×1013 B atoms/cm2) were grown on Si (100) by molecular beam epitaxy at different substrate temperatures and cap layer compositions (Si and Si0.8Ge0.2). Close to the delta interface the B profiles are characterized by an exponential decay in growth direction. For the Si cap the results suggest the existence of a transition from equilibrium segregation (exponential decay length ≂20 nm) to kinetically limited segregation (transition temperature ≂600 °C at 0.1 nm/s). The doping profiles also give evidence of a temporal change of the segregation coefficient which is probably caused by clustering of segregating B atoms.
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61.72.uf Ge and Si
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Ion irradiation enhanced crystal nucleation in amorphous Si thin films

J. S. Im and Harry A. Atwater

Appl. Phys. Lett. 57, 1766 (1990); http://dx.doi.org/10.1063/1.104061 (3 pages) | Cited 33 times

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The nucleation kinetics of the amorphous‐to‐crystal transition of Si films under 1.5 MeV Xe+ irradiation have been investigated by means of in situ transmission electron microscopy in the temperature range T=500–580 °C. After an incubation period during which negligible nucleation occurs, a constant nucleation rate was observed in steady state, suggesting that homogeneous nucleation occurred. Compared to thermal crystallization, a significant enhancement in the nucleation rate during high‐energy ion irradiation (five to seven orders of magnitude) was observed with an apparent activation energy of 3.9±0.75 eV.
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61.80.Jh Ion radiation effects
81.40.Ef Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization
64.60.Q- Nucleation

Observation of miniband formation in the CdTe/Cd1−xMnxTe quantum well system

Alex Harwit, C. Hsu, F. Agulló‐Rueda, and L. L. Chang

Appl. Phys. Lett. 57, 1769 (1990); http://dx.doi.org/10.1063/1.104062 (3 pages) | Cited 1 time

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We report the effects of perpendicular electric fields on the eigenenergies of the CdTe/Cd1−xMnxTe quantum well system. The samples are probed at 6 K using photoluminescence. In an electric field, the photoluminescence spectra of wide‐barrier quantum well samples red shifted, consistent with the quantum‐confined Stark effect. The spectra of narrow‐barrier superlattice samples blue shifted, indicative of miniband reduction to localized states. A linear blue shift was observed up to a field of 50 kV/cm after which saturation occurred. Additionally, we have observed luminescence which appeared to arise from transitions between adjacent wells. No striking effects were observed at the paramagnetic‐spin glass transition temperature.
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78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
78.20.Jq Electro-optical effects
73.61.Ga II-VI semiconductors

Impact ionization in the base of a hot‐electron AlSb/InAs bipolar transistor

Arvind S. Vengurlekar, Federico Capasso, and T. Heng Chiu

Appl. Phys. Lett. 57, 1772 (1990); http://dx.doi.org/10.1063/1.104063 (3 pages) | Cited 1 time

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The operation of a new AlSb/InAs heterojunction bipolar transistor is studied. The electrons are injected into a p‐InAs base across the AlSb/InAs heterojunction. The conduction‐band discontinuity at this heterojunction is sufficiently large so that energy of the electrons injected into InAs exceeds the threshold for generating electron‐hole pairs by impact ionization. The observed incremental common base current at zero collector‐base bias decreases and becomes negative as the emitter current is increased, thus providing direct evidence for impact ionization entirely by band‐edge discontinuities.
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73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
85.30.Pq Bipolar transistors
79.20.Kz Other electron-impact emission phenomena

Photoreflectance study of gallium arsenide grown on Si

M. Dutta, H. Shen, S. M. Vernon, and T. M. Dixon

Appl. Phys. Lett. 57, 1775 (1990); http://dx.doi.org/10.1063/1.104121 (3 pages) | Cited 8 times

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Low‐temperature linear polarized photoreflectance is used to study the stress and its release in thick GaAs grown on Si. We find that the GaAs layer is mainly composed of two regions with two kinds of stress, biaxial and uniaxial. Four features, two from each region due to the split valence band, are observed. Their polarization selection rules enable us to distinguish the nature of the strain as well as the nature of the transitions.
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68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors

ac conductance measurements on radiation‐damaged (100) Si/SiO2 interface after defect transformation

Lakshmanna Vishnubhotla, Wenliang Chen, and T. P. Ma

Appl. Phys. Lett. 57, 1778 (1990); http://dx.doi.org/10.1063/1.104064 (3 pages) | Cited 4 times

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We report experimental results of multifrequency ac conductance measurements on radiation‐damaged (100) Si‐SiO2 interface after the interfacial defect transformation process has taken place. Previous quasi‐static capacitance‐voltage measurements on such samples have identified two distinct interface trap peaks, one above midgap and the other below midgap. The presence of such a double‐peak interface trap distribution has been confirmed by our ac conductance measurements, and excellent quantitative agreement with the capacitance measurements has been achieved. In addition, the ac conductance measurements showed a strong energy dependence of the capture cross sections of interface traps for both electrons (in the upper half of the band gap) and holes (in the lower half of the band gap). The capture cross sections vary systematically by more than an order of magnitude in an energy range of about 200 meV in either half of the band gap, suggesting that there may be a broad distribution of different defect configurations and/or their surrounding environments at the interface after radiation damage. The energy dispersion of the interface trap time constants and surface potential fluctuations are also obtained and used for accurate extraction of the interface trap density from these data.
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73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
61.80.Cb X-ray effects

Higher order electron cyclotron resonances in n‐type HgTe‐CdTe superlattices

M. Dobrowolska, T. Wojtowicz, J. K. Furdyna, J. R. Meyer, R. D. Feldman, R. F. Austin, and L. R. Ram‐Mohan

Appl. Phys. Lett. 57, 1781 (1990); http://dx.doi.org/10.1063/1.104040 (3 pages) | Cited 3 times

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Temperature‐dependent magneto‐optical measurements on an n‐type HgTe‐CdTe superlattice have been compared to the results of a comprehensive new theory, which fully incorporates the complexities of the unusual superlattice band structure. The theory predicts that higher order cyclotron resonance processes should yield a separate transmission minimum which is distinct from that of the lowest order cyclotron transition, and the data provide an unambiguous confirmation of this prediction. Since the energy gap is near zero, interband transitions are also observed in the same spectral range as the cyclotron resonance.
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78.20.Ls Magneto-optical effects
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
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