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5 Nov 1990

Volume 57, Issue 19, pp. 1949-2034

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Mirrorless all‐optical bistability in polymer dispersed liquid crystals

F. Simoni, G. Cipparrone, and C. Umeton

Appl. Phys. Lett. 57, 1949 (1990); http://dx.doi.org/10.1063/1.104017 (3 pages) | Cited 8 times

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We report the observation of a bistable behavior from dye‐doped polymer dispersed liquid crystals. The interpretation of the phenomenon is given in the theoretical framework of an absorption which increases with the excitation of the material.
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42.65.Pc Optical bistability, multistability, and switching, including local field effects
78.20.Bh Theory, models, and numerical simulation
78.20.-e Optical properties of bulk materials and thin films

Temperature dependence of optical phase conjugation in semiconductor‐doped glasses

T. Dutton, A. Dvornikov, B. Van Wonterghem, and P. M. Rentzepis

Appl. Phys. Lett. 57, 1952 (1990); http://dx.doi.org/10.1063/1.104119 (3 pages) | Cited 4 times

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We measured optical phase conjugation via low‐power degenerate four‐wave mixing at 532 nm as a function of temperature in semiconductor‐microcrystallite‐doped glasses. We find that the overall efficiency of the phase conjugation process increases with decreasing temperature and is temperature independent between 77 and 100 K. The results are interpreted as the combined effect of the increased transmission due to the increased band gap and an effective χ(3) which increased due to a decrease of the trapped carrier recombination rate.
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42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
42.70.Ce Glasses, quartz
78.20.-e Optical properties of bulk materials and thin films

Polarization characteristics of AlGaAs/GaAs double‐heterostructure lasers grown on Si substrates

Xiaoming Liu, Henry P. Lee, and Shyh Wang

Appl. Phys. Lett. 57, 1955 (1990); http://dx.doi.org/10.1063/1.104018 (3 pages) | Cited 1 time

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The polarization of laser radiations from AlGaAs/GaAs double‐heterostructure lasers grown on planar, trenched, and SiN‐patterned Si substrates are examined. It was found that TM modes lase first in most of these lasers. Competition between TE and TM modes also occurs in some devices. A qualitative explanation is given on the basis of stress‐induced changes in the optical gains between TE and TM modes. The difference in the polarization behavior among these lasers indicates that the residual tensile stress is influenced by substrate patterning.
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42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation
42.60.Fc Modulation, tuning, and mode locking
42.55.Px Semiconductor lasers; laser diodes

Microwave diffraction and interference in reflection using transient radiation from optoelectronically pulsed antennas

W. M. Robertson, G. Arjavalingam, and G. V. Kopcsay

Appl. Phys. Lett. 57, 1958 (1990); http://dx.doi.org/10.1063/1.103995 (3 pages)

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Broadband (15–130 GHz) microwave interference and diffraction are demonstrated in a reflection configuration using transient radiation from optoelectronically pulsed antennas. The measured complex reflection function of Fabry–Perot interferometers and diffraction from amplitude gratings are presented. The effectiveness of the technique for quantifying the scattering from general three‐dimensional objects is discussed.
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41.20.Jb Electromagnetic wave propagation; radiowave propagation
07.90.+c Other topics in instruments, apparatus, and components common to several branches of physics and astronomy (restricted to new topics in section 07)

High‐power, widely tunable, picosecond coherent source from optical parametric amplification in barium borate

J. Y. Huang, J. Y. Zhang, Y. R. Shen, C. Chen, and B. Wu

Appl. Phys. Lett. 57, 1961 (1990); http://dx.doi.org/10.1063/1.103980 (3 pages) | Cited 17 times

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We report the performance of a type‐I barium borate optical parametric amplifier pumped by 15 ps, 355 nm laser pulses. We show that it is possible to obtain narrowband (≂3 Å), high‐energy (≥200 μJ), widely tunable (0.4–2 μm) picosecond pulses with a maximum pump‐to‐signal energy conversion better than 30%.
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42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
42.70.-a Optical materials
42.60.Fc Modulation, tuning, and mode locking
42.60.Da Resonators, cavities, amplifiers, arrays, and rings

Insulated‐gate multiple quantum well optical modulator on InP

C. W. Chen, R. Iyer, H. Y. Lee, M. Hafich, G. Y. Robinson, and D. L. Lile

Appl. Phys. Lett. 57, 1964 (1990); http://dx.doi.org/10.1063/1.103981 (3 pages)

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Insulated‐gate metal‐insulator‐semiconductor (MIS) diodes have been fabricated on multiple quantum well stacks of InP/InGaAs grown by gas‐source molecular beam epitaxy. These devices have shown excitonic resonances and optical modulation spectra in pass‐through operation similar in shape, but smaller in magnitude, to what has been previously reported with p‐i‐n and Schottky diode structures. Compared to these other devices the MIS modulator has the advantage of being totally planar with excellent interdevice electrical isolation suggesting its suitability for high complexity array applications.
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42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
85.60.-q Optoelectronic devices

Cut‐off characteristics of leaky Sezawa and pseudo‐Sezawa wave modes for thin‐film characterization

J. Kushibiki, T. Ishikawa, and N. Chubachi

Appl. Phys. Lett. 57, 1967 (1990); http://dx.doi.org/10.1063/1.103982 (3 pages) | Cited 17 times

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A new method of determining the elastic constants, density, and thickness of thin‐film materials with the line‐focus‐beam acoustic microscope is developed using propagation characteristics of leaky Sezawa and pseudo‐Sezawa waves in the neighborhood of the cut‐off region. It is demonstrated for a sample of gold film on fused quartz that the values of the stiffness constant, C44, and density are, respectively, about 11% and 5.5% less than those for polycrystalline bulk gold, and the thickness is determined as 6370 Å.
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43.35.Cg Ultrasonic velocity, dispersion, scattering, diffraction, and attenuation in solids; elastic constants
43.35.Ns Acoustical properties of thin films
43.35.Pt Surface waves in solids and liquids
43.35.Yb Ultrasonic instrumentation and measurement techniques

Crystallization of amorphous Si on a glass substrate through nucleation by Si+ ion implantation

Tomonori Yamaoka, Keiji Oyoshi, Takashi Tagami, Yasunori Arima, Ken Yamashita, and Shuhei Tanaka

Appl. Phys. Lett. 57, 1970 (1990); http://dx.doi.org/10.1063/1.103983 (3 pages) | Cited 8 times

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Crystallization of amorphous Si films on a glass substrate by Si+ implantation (acceleration energy: 180 keV, beam current density: 10 μA/cm, ion dose: 1×1017 ions/cm2) was performed without external heating of the substrate. Transmission electron microscopy images of the crystallized specimens lead to the following conclusions: (1) crystallization was achieved through bulk nucleation by Si+ implantation, which is a low temperature and rapid process compared with the ordinary thermal process, (2) the crystallization is strongly related to the ion‐solid interaction, not due to ‘‘pure’’ thermal annealing by ion beam heating.
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61.80.Jh Ion radiation effects
81.15.Np Solid phase epitaxy; growth from solid phases
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
85.40.Hp Lithography, masks and pattern transfer

Antiparallel crystal orientation in CoSi2 epitaxial bilayers formed by ion implantation

M. F. Wu, A. Vantomme, G. Langouche, K. Maex, H. Vanderstraeten, and Y. Bruynseraede

Appl. Phys. Lett. 57, 1973 (1990); http://dx.doi.org/10.1063/1.104148 (3 pages) | Cited 14 times

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Orientation and strain in buried CoSi2 layers have been studied in a Si/CoSi2/Si/CoSi2/Si(111) structure. Using a well defined implantation and annealing procedure, a unique combination of CoSi2 epitaxial layers was obtained having the same strain but an opposite orientation. These novel structures are interesting for epitaxial growth studies and may have important device applications.
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68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
68.35.B- Structure of clean surfaces (and surface reconstruction)

Chemically enhanced self‐sputtering of carbon

J. W. Davis and A. A. Haasz

Appl. Phys. Lett. 57, 1976 (1990); http://dx.doi.org/10.1063/1.103984 (2 pages) | Cited 7 times

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New results obtained for graphite self‐sputtering, in the presence of thermal atomic hydrogen, show that chemically enhanced self‐sputtering (CES) can exceed unity erosion yield even at normal angles of incidence. CES yields were found to depend on the ϕC+/ϕH0 flux ratio and graphite temperature, with peak erosion occurring at about 800 K. No dependence on angles of incidence was observed.
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81.15.Cd Deposition by sputtering
81.65.-b Surface treatments
52.25.Vy Impurities in plasmas

Convergent beam electron diffraction study of lattice distortion in InGaAs/GaAs strained‐layer superlattices grown by metalorganic chemical vapor deposition

Q. H. Xie, K. K. Fung, P. K. York, G. E. Fernandez, J. A. Eades, and J. J. Coleman

Appl. Phys. Lett. 57, 1978 (1990); http://dx.doi.org/10.1063/1.103985 (3 pages) | Cited 8 times

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The intensities of sidebands in convergent beam electron diffraction reflections from plan‐view specimens of strain modulated InGaAs/GaAs superlattices are dependent on the natural lattice mismatch, the ratio of the thicknesses of the superlattice layers, the period (sum of layer thicknesses) of the superlattice, and the g vectors of the reflections. The intensities of kinematic higher‐order Laue zone (HOLZ) reflections have been calculated from a simple model based on alternate contraction and expansion of lattice spacings of the superlattice layers. An accurate estimate of the In content of InGaAs can be deduced from the elastic strains in the superlattice layers so obtained.
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61.05.jh Low-energy electron diffraction (LEED) and reflection high-energy electron diffraction (RHEED)
07.79.Cz Scanning tunneling microscopes
61.05.-a Techniques for structure determination
81.30.-t Phase diagrams and microstructures developed by solidification and solid-solid phase transformations
68.55.-a Thin film structure and morphology

Chemical reaction at the ZnSe/GaAs interface detected by Raman spectroscopy

A. Krost, W. Richter, D. R. T. Zahn, K. Hingerl, and H. Sitter

Appl. Phys. Lett. 57, 1981 (1990); http://dx.doi.org/10.1063/1.104149 (2 pages) | Cited 29 times

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When ZnSe is deposited at temperatures commonly used for epitaxy onto GaAs, the possibility arises that selenium or zinc reacts with the substrate and thin interfacial layers consisting of a gallium selenide or a zinc arsenide are formed. In particular, Ga2Se3, which is thermodynamically the most stable, has been suggested as a likely candidate. In this study we present evidence for the formation of Ga2Se3 using Raman spectroscopy as a fingerprint technique. Ga2Se3 layers were grown on GaAs and the Raman spectra thereof were compared with those of ZnSe/GaAs heterostructures.
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82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces
78.30.Fs III-V and II-VI semiconductors
68.35.Fx Diffusion; interface formation
68.35.Md Surface thermodynamics, surface energies

High‐resolution transmission electron microscopy of GaAs/AlAs heterointerfaces grown on the misoriented substrate in the 〈110〉 projection

Nobuyuki Ikarashi, Akira Sakai, Toshio Baba, Koichi Ishida, Junich Motohisa, and Hiroyuki Sakaki

Appl. Phys. Lett. 57, 1983 (1990); http://dx.doi.org/10.1063/1.103986 (3 pages) | Cited 7 times

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Edge‐on observations of the structures of vicinal interfaces of GaAs/AlAs heterostructures were carried out by high‐resolution electron microscopy. In order to observe the interfacial steps running along the 〈110〉 direction edge‐on, we demonstrate the imaging conditions for high‐resolution observations in the 〈110〉 projection. Under these conditions, the structures of GaAs/AlAs interfaces, which were grown on the vicinal (001) substrate tilted toward [110], are examined in the [110] projection. The interfacial structures are imaged edge‐on, so that the monolayer height steps were observed. The results reveal fluctuations of terrace width and the roughness of step edges on an atomic scale.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.55.-a Thin film structure and morphology
68.35.Fx Diffusion; interface formation

Thermal quenching of the photoluminescence of InGaAs/GaAs and InGaAs/AlGaAs strained‐layer quantum wells

J. D. Lambkin, D. J. Dunstan, K. P. Homewood, L. K. Howard, and M. T. Emeny

Appl. Phys. Lett. 57, 1986 (1990); http://dx.doi.org/10.1063/1.103987 (3 pages) | Cited 78 times

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Photoluminescence in InGaAs/GaAs strained‐layer quantum wells is strongly quenched by temperatures above 10–100 K, depending on the well width. Analysis of this dependence shows that the quenching mechanism is thermal activation of electron‐hole pairs from the wells into the GaAs barriers, followed by nonradiative recombination through a loss mechanism in bulk GaAs. The addition of Al to the barriers to improve confinement eliminates loss through this route but introduces another loss mechanism, characterized by an activation energy independent of well width and with a smaller pre‐exponential factor.
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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

Optical properties of SnOx thin films: Theory and experiment

B. Stjerna and C. G. Granqvist

Appl. Phys. Lett. 57, 1989 (1990); http://dx.doi.org/10.1063/1.104150 (3 pages) | Cited 11 times

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Transparent and conducting SnOx thin films were made by reactive rf magnetron sputtering of Sn in Ar+O2 onto unheated glass. Optical and electrical properties were reconciled with a quantitative model for wide band‐gap semiconductors. The theory is based on heavy n doping by doubly ionized oxygen vacancies and ionized impurity scattering of the free electrons.
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78.66.-w Optical properties of specific thin films
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
81.40.Tv Optical and dielectric properties related to treatment conditions
81.15.Cd Deposition by sputtering

Peak electron mobilities between 2.75 and 3.32×105 cm2 V−1 s−1 in GaAs grown by molecular beam epitaxy with As2

C. R. Stanley, M. C. Holland, and A. H. Kean

Appl. Phys. Lett. 57, 1992 (1990); http://dx.doi.org/10.1063/1.103988 (3 pages) | Cited 2 times

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Exceptionally pure n‐GaAs has been grown without intentional doping by solid‐source molecular beam epitaxy (MBE) using arsenic dimers (As2). Peak electron mobilities in the range 2.75–3.32×105 cm2 V−1 s−1 at temperatures of ≊40–50 K with free‐electron densities n=1×1014 cm−3 have been measured for a series of layers grown under a variety of conditions. These mobilities are among the highest recorded for MBE‐grown GaAs.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
72.20.Fr Low-field transport and mobility; piezoresistance
73.61.Ey III-V semiconductors
78.55.Cr III-V semiconductors

Photobleaching of light‐induced paramagnetic defects in amorphous silicon nitride films

M. S. Crowder, E. D. Tober, and J. Kanicki

Appl. Phys. Lett. 57, 1995 (1990); http://dx.doi.org/10.1063/1.104151 (3 pages) | Cited 21 times

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We report for the first time the photobleaching of light‐induced paramagnetic defects in nitrogen‐rich hydrogenated amorphous‐silicon nitride thin films. We have determined the photon energy dependence and the stretched exponential time dependence for photoproduction and the subsequent photobleaching of the light‐induced electron spin resonance signal. Photobleaching is a reversible process that occurs at low temperature (100 K) and at room temperature. These findings are in support of an optically induced rearrangement of charges in existing defects as an important light‐induced effect in a‐SiN1.6@B:H.
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76.30.Lh Other ions and impurities
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
71.55.Ht Other nonmetals
73.61.Ng Insulators

InAs/InP strained single quantum wells grown by atmospheric pressure organometallic vapor phase epitaxy

R. P. Schneider and B. W. Wessels

Appl. Phys. Lett. 57, 1998 (1990); http://dx.doi.org/10.1063/1.103989 (3 pages) | Cited 40 times

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Strained InAs/InP single quantum wells of nominal thickness 1–11 monolayers have been prepared using organometallic vapor phase epitaxy in an atmospheric pressure reactor. For wells of thickness 1–3 ML grown using optimal flow modulation parameters, the surface morphology was specular and narrow single‐line photoluminescent emission was observed. For thicker wells, the evolution of additional PL features and the appearance of island‐like features on the sample surface was attributed to the onset of three‐dimensional (island) growth.
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81.15.Kk Vapor phase epitaxy; growth from vapor phase
78.55.Cr III-V semiconductors

Effect of AlGaAs window and buffer layers on the response characteristics of GaAs photoconductive detectors

H. J. Youn, R. B. Darling, and K. J. Kuhn

Appl. Phys. Lett. 57, 2001 (1990); http://dx.doi.org/10.1063/1.103990 (3 pages) | Cited 1 time

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Five comparative GaAs‐based photoconductive detectors were fabricated to investigate the effects of AlGaAs window and buffer layers on device performance. Steady‐state and transient photoconductive responses were measured on structures with and without an AlGaAs window layer over the photoconductive layer, and with and without an AlGaAs buffer layer between the photoconductive layer and substrate. The structure with both an AlGaAs window and AlGaAs buffer layer shows the lowest dark current (<1 nA) and the highest responsivity (∼ 0.2 A/W). However, the structure on a bare semi‐insulating GaAs substrate shows the fastest pulse response of ∼ 800 ps full width at half maximum, indicating that interfacial rather than bulk properties dominate the photoconductive characteristics.
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85.60.Gz Photodetectors (including infrared and CCD detectors)
72.40.+w Photoconduction and photovoltaic effects
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping

Microsecond carrier lifetimes in strained silicon‐germanium alloys grown by rapid thermal chemical vapor deposition

P. V. Schwartz and J. C. Sturm

Appl. Phys. Lett. 57, 2004 (1990); http://dx.doi.org/10.1063/1.103991 (3 pages) | Cited 6 times

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We report generation lifetimes of over 1 μs in Si0.82Ge0.18 epitaxial strained layers grown by rapid thermal chemical vapor deposition on silicon substrates. By using a pulsed metal‐oxide‐semiconductor capacitor technique, we were able to probe the minority‐carrier properties of a layer of Si0.82Ge0.18 sandwiched between two epitaxial layers of silicon. We also show that the band gap and the intrinsic carrier concentration are important when relating experimental results to the generation lifetime τg.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
73.61.Ey III-V semiconductors

Realization of low defect density, ultrathick, strained InGaAs/GaAs multiple quantum well structures via growth on patterned GaAs (100) substrates

A. Madhukar, K. C. Rajkumar, Li Chen, S. Guha, K. Kaviani, and R. Kapre

Appl. Phys. Lett. 57, 2007 (1990); http://dx.doi.org/10.1063/1.103992 (3 pages) | Cited 12 times

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Growth of low defect density highly strained InxGa1−xAs/GaAs multiple quantum well (MQW) structures of thicknesses suited for application in spatial light modulator (SLM) devices operating in infrared has been thwarted by the occurrence of strain‐induced defects. Exploiting the notion of strain relief at mesa edges, we report here the first realization of very low defect density MQW structures of thickness as high as 2.38 μm at x=0.20. This has opened up the possibility of realizing a variety of reflective and transmissive SLM structures which also fruitfully exploit the transparent nature of the substrate.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
42.79.Hp Optical processors, correlators, and modulators
61.72.sd Impurity concentration
61.72.sh Impurity distribution
61.72.sm Impurity gradients

In situ doping in silicon selective epitaxial growth at 800 °C by ultralow‐pressure chemical vapor deposition

Tri‐Rung Yew and Rafael Reif

Appl. Phys. Lett. 57, 2010 (1990); http://dx.doi.org/10.1063/1.103993 (3 pages) | Cited 4 times

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In situ doping capabilities, n and p type, in silicon selective epitaxial growth by ultralow‐pressure chemical vapor deposition are presented in this letter. Selective epitaxial layers were grown at 800 °C after an in situ Ar/H2 plasma sputter clean. The n‐ and p‐type dopant sources were 1000 ppm arsine and 1000 ppm diborane, respectively, in silane mixed with pure silane for dilution. It was found that high structural quality in situ doped selective epitaxial layers with n‐ or p‐type dopant concentration of 1018 cm−3 can be obtained.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
73.61.Ng Insulators
81.15.Kk Vapor phase epitaxy; growth from vapor phase
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

All‐organic thin‐film transistors made of alpha‐sexithienyl semiconducting and various polymeric insulating layers

Xuezhou Peng, Gilles Horowitz, Denis Fichou, and Francis Garnier

Appl. Phys. Lett. 57, 2013 (1990); http://dx.doi.org/10.1063/1.103994 (3 pages) | Cited 79 times

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Thin‐film transistors (TFTs) were fabricated with a variety of organic polymer insulators topped with a vacuum evaporated organic semiconductor, α‐sexithienyl (α6T). No field‐enhanced source‐drain current was obtained with polystyrene (PSt) and polymethylmethacrylate (PMMA). The field‐enhanced current is weak with polyvinyl chloride (PVC), but much stronger with polyvinyl alcohol (PVA) and cyanoethylpullulan (CYEPL), a cyanoethylated polysaccharide which possesses a high dielectric constant (ϵr=18.5 at 10 kHz). In these last two instances, the field‐effect mobility surpasses the one measured on TFTs made on a SiO2 insulating layer. A strong correlation is found between the dielectric constant of the insulator and the field‐effect mobility.
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85.30.Tv Field effect devices
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
73.61.Cw Elemental semiconductors
73.61.Jc Amorphous semiconductors; glasses
73.61.Le Other inorganic semiconductors
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy

Effect of small changes in composition on the electrical and structural properties of YBa2Cu3O7 thin films

N. G. Chew, S. W. Goodyear, J. A. Edwards, J. S. Satchell, S. E. Blenkinsop, and R. G. Humphreys

Appl. Phys. Lett. 57, 2016 (1990); http://dx.doi.org/10.1063/1.104152 (3 pages) | Cited 58 times

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Epitaxial thin films of YBa2Cu3O7 have been grown in situ by evaporation onto (001) MgO substrates. The composition was varied systematically to investigate the effects of changes in Cu content and Ba/Y ratio on the film properties. The results demonstrate that deviations from stoichiometry at the limit of resolution of most analytic techniques can have a large effect on structural and transport properties, as well as causing marked changes in surface morphology. The best properties (Jc≳3×106 A/cm2 at 77 K) are only found for a narrow range of compositions, which can be readily identified from the surface morphology.
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74.25.Sv Critical currents
74.62.Bf Effects of material synthesis, crystal structure, and chemical composition
74.70.-b Superconducting materials other than cuprates
74.78.-w Superconducting films and low-dimensional structures

Epitaxially grown sputtered LaAlO3 films

A. E. Lee, C. E. Platt, J. F. Burch, R. W. Simon, J. P. Goral, and M. M. Al‐Jassim

Appl. Phys. Lett. 57, 2019 (1990); http://dx.doi.org/10.1063/1.104153 (3 pages) | Cited 36 times

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We have grown crystalline thin films of LaAlO3 using off‐axis rf sputtering from a single stoichiometric target. The films grow epitaxially on SrTiO3 and LaAlO3  (100) substrates as well as on YBa2Cu3O7 thin films. We report on the growth conditions used to make these films, the properties of the films, and the properties of bilayer and trilayer structures containing both LaAlO3 and YBa2Cu3O7 films. Transmission electron microscopy cross‐sectional and x‐ray diffraction analyses indicate that all the constituent films in the multilayers grow epitaxially and that the interfaces between the films are sharply defined. Preliminary transport measurements on these multilayers show that LaAlO3 can be used for dielectric layers in a variety of high‐temperature superconductor electronic circuits.
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74.78.-w Superconducting films and low-dimensional structures
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
77.55.-g Dielectric thin films
81.15.Cd Deposition by sputtering
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