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30 May 1988

Volume 52, Issue 22, pp. 1845-1923

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Broadly tunable yellow‐green laser using color centers in a LiF crystal at room temperature

Hongen Gu, Lan Qi, and Liangfeng Wan

Appl. Phys. Lett. 52, 1845 (1988); http://dx.doi.org/10.1063/1.99634 (2 pages) | Cited 9 times

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A broadly tunable yellow‐green laser using F+3 centers and some unknown centers in a LiF crystal at room temperature is reported. The laser output extended from 500 to 640 nm and peaked at 535 and 610 nm.
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42.60.Fc Modulation, tuning, and mode locking
42.55.Rz Doped-insulator lasers and other solid state lasers
42.60.By Design of specific laser systems
78.45.+h Stimulated emission

Intrinsic efficiency comparison in various low‐pressure XeF laser mixtures pumped at high excitation rates and with short‐pulse electron beam pumping

Naoto Nishida, Frank K. Tittel, Hiroshi Kumagai, Young‐Woo Lee, and Minoru Obara

Appl. Phys. Lett. 52, 1847 (1988); http://dx.doi.org/10.1063/1.99618 (3 pages) | Cited 2 times

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A comparison of XeF(B→X) laser efficiency is reported using four different gas mixtures at room temperature, i.e., Ar/Xe/F2 , Ar/Xe/NF3 , Ne/Xe/F2 , and Ne/Xe/NF3 . All mixtures were pumped at the same high excitation rate of 1.1 MW/cm3 with a 65 ns electron beam current pulse. The respective pressure for the Ne‐based mixtures was 1170 Torr and for the Ar‐based mixtures was 711 Torr. The measured intrinsic efficiency of all four mixtures was ∼2%, which is comparable to those reported in high‐pressure mixtures pumped at low excitation rates with long electron beam pumping.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.55.-f Lasers

Linear 1×2 directional coupler for electromagnetic field detection

Marta McWright Howerton, Catherine H. Bulmer, and William K. Burns

Appl. Phys. Lett. 52, 1850 (1988); http://dx.doi.org/10.1063/1.99731 (3 pages) | Cited 3 times

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A 1×2 directional coupler which can be used as an integrated optical electromagnetic field detector is described. Modulators have been formed from titanium‐indiffused lithium niobate waveguides operating at the 1.3 μm wavelength. Linear dynamic ranges of 74.3 dB with 190 μW light and 76.3 dB with 760 μW light were observed for separate devices. Voltage sensitivity measurements are in good agreement with theoretical predictions. A 3.1 μV rms sensitivity was obtained for a device with a 10 mm electrode length.
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42.79.Gn Optical waveguides and couplers
42.82.-m Integrated optics
78.20.Jq Electro-optical effects
84.40.Az Waveguides, transmission lines, striplines

Stimulated emission in ultrathin (20 Å) AlxGa1−xAs‐GaAs single quantum well heterostructures

Y. C. Lo, K. Y. Hsieh, and R. M. Kolbas

Appl. Phys. Lett. 52, 1853 (1988); http://dx.doi.org/10.1063/1.99619 (3 pages) | Cited 10 times

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Spontaneous and stimulated emission spectra from a series of AlxGa1−xAs‐GaAs single quantum well heterostructures are demonstrated for well widths as thin as 20 Å. These undoped samples, grown by molecular beam epitaxy, are the thinnest single quantum wells ever reported to support stimulated emission. Laser thresholds are generally quite low (1.2 kW/cm2) despite the fact that the single well is undoped and of dimensions which were previously thought to be too small to effectively collect excess carriers (Lz≪scattering path length). A simple model based on the spatial extent of the wave function, rather than the well width, is proposed to explain the experimental results.
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42.55.Px Semiconductor lasers; laser diodes
78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
78.45.+h Stimulated emission

Direct dissociation of F2 in electron beam pumped excimer lasers: The effect on electron density

Mark J. Kushner and Thomas J. Moratz

Appl. Phys. Lett. 52, 1856 (1988); http://dx.doi.org/10.1063/1.99606 (3 pages) | Cited 5 times

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The electron impact dissociation of molecular fluorine in XeF and KrF excimer lasers is examined. Two methods of dissociation are discussed: dissociative attachment and direct neutral dissociation by excitation to the dissociative electronic states a3Πu and A1Πu. Computer models for the kinetics of the lasers are parameterized, and predictions of electron density are compared to experimental results for electron beam pumped Ne/Xe/F2 gas mixtures [W. D. Kimura, D. R. Guyer, S. E. Moody, J. F. Seamans, and D. H. Ford, Appl. Phys. Lett. 50, 60 (1987)]. To obtain agreement with experiment, the ratio of direct dissociation to dissociative attachment must be ≥2. The implications of these results with respect to electron quenching and the validation of computer models are discussed.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.55.-f Lasers
34.80.Gs Molecular excitation and ionization

Large‐numerical‐aperture InP lenslets by mass transport

Z. L. Liau, V. Diadiuk, J. N. Walpole, and D. E. Mull

Appl. Phys. Lett. 52, 1859 (1988); http://dx.doi.org/10.1063/1.99607 (3 pages) | Cited 14 times

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Lenslets with diameters up to 130 μm and numerical apertures of 0.39–0.75 have been formed in InP substrates by using mass transport to smooth out chemically etched multilevel mesa structures. The lenslets show a smooth surface with an accurately controlled profile (i.e., curvatures) and are capable of forming clear images. Some lenslets (with a diameter of approximately 67 μm) have been used to collimate the output of a buried‐heterostructure diode laser (of 1.3 μm wavelength) and resulted in a nearly diffraction‐limited beam divergence of 1.4°.
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42.15.Eq Optical system design
42.79.Bh Lenses, prisms and mirrors
66.30.H- Self-diffusion and ionic conduction in nonmetals
42.55.Mv Dye lasers

Electron densities in xenon chloride laser mixtures

T. H. Johnson and H. E. Cartland

Appl. Phys. Lett. 52, 1862 (1988); http://dx.doi.org/10.1063/1.99608 (3 pages) | Cited 3 times

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A new, comprehensive kinetic model has been used to calculate the time‐dependent behavior of electron number density in electron‐beam‐pumped XeCl excimer laser gas mixtures. Predictions of the model are compared to recently published experimental results and are shown to be in good agreement for moderate and high HCl concentrations (≥0.12%). At low HCl concentration a clear discrepancy is apparent, one which cannot be explained by assuming any reasonable electron energy distribution.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers

Laser direct writing of aluminum conductors

T. Cacouris, G. Scelsi, P. Shaw, R. Scarmozzino, R. M. Osgood, and R. R. Krchnavek

Appl. Phys. Lett. 52, 1865 (1988); http://dx.doi.org/10.1063/1.99609 (3 pages) | Cited 25 times

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We report, for the first time, the laser direct writing of high‐conductivity aluminum interconnects from dimethylaluminum hydride (DMAlH). These lines were deposited from this metalorganic gas using a focused deep‐ultraviolet laser beam, and the deposition process was studied as a function of several process parameters. Electrical measurements and Auger electron spectroscopy were used to characterize the quality of the laser‐deposited films.
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85.40.Ls Metallization, contacts, interconnects; device isolation
85.40.Hp Lithography, masks and pattern transfer
73.61.At Metal and metallic alloys
81.05.Bx Metals, semimetals, and alloys

Photon‐controlled fabrication of amorphous superlattice structures using ArF (193 nm) excimer laser photolysis

D. H. Lowndes, D. B. Geohegan, D. Eres, S. J. Pennycook, D. N. Mashburn, and G. E. Jellison

Appl. Phys. Lett. 52, 1868 (1988); http://dx.doi.org/10.1063/1.99732 (3 pages) | Cited 5 times

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Pulsed ArF (193 nm) excimer laser photolysis of disilane, germane, and disilane‐ammonia mixtures has been used to deposit amorphous superlattices containing silicon, germanium, and silicon nitride layers. Transmission electron microscope cross‐section views demonstrate that structures having thin (5–25 nm) layers and sharp interlayer boundaries can be deposited at substrate temperatures below the pyrolytic threshold, entirely under laser photolytic control.
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68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
81.15.Jj Ion and electron beam-assisted deposition; ion plating
82.50.Bc Processes caused by infrared radiation
82.50.Hp Processes caused by visible and UV light
78.66.-w Optical properties of specific thin films
78.67.-n Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures

Mass‐dispersive recoil spectrometry studies of oxygen and nitrogen redistribution in ion‐beam‐synthesized buried oxynitride layers in silicon

Harry J. Whitlow, C. Sture Petersson, Karen J. Reeson, and Peter L. F. Hemment

Appl. Phys. Lett. 52, 1871 (1988); http://dx.doi.org/10.1063/1.99733 (3 pages) | Cited 4 times

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Mass‐dispersive recoil spectrometry has been employed to study the influence of annealing conditions in ion‐beam‐synthesized silicon oxynitride structures prepared by implantation of 1.8×1018 and 1×1017 200 keV 16O+ and 14N+ ions cm−2, respectively, at approximately 600 °C. Subsequent annealing at 1200 and 1300 °C leads to redistribution of the implanted oxygen to form a buried oxide layer with nitrogen segregation to the buried SiO2/Si interfaces. Implantation with N+ subsequent to O+ followed by annealing at 1200 °C for 2 h was found to lead to both a lower oxygen content and lower channeling detectable defect concentration in the overlying silicon film than if the order of implantation was reversed. No significant dependence on order of implantation was observed after annealing at 1300 °C for 5 h.
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68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.80.Jh Ion radiation effects
81.40.Ef Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization
66.30.J- Diffusion of impurities

Strain relaxation in low lattice mismatch epitaxy of CdTe/Cd0.97Zn0.03Te (001) by channeling

A. C. Chami, E. Ligeon, R. Danielou, J. Fontenille, G. Lentz, N. Magnea, and H. Mariette

Appl. Phys. Lett. 52, 1874 (1988); http://dx.doi.org/10.1063/1.99610 (3 pages) | Cited 5 times

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A measurement of the misfit dislocation density at the CdTe(001)/Cd0.97Zn0.03Te (001) interface has been obtained by channeling. This method allows an accurate determination of the critical thickness (390 nm) and appears sensitive for misfit dislocation density determination in systems with lattice mismatch as low as Δa/a≂3×10−4. The formation energy of misfit dislocations is estimated to be about 10−8 J/m.
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68.35.Gy Mechanical properties; surface strains
61.85.+p Channeling phenomena (blocking, energy loss, etc.)

Fine structure of the alloy‐broadened thermal emission spectra from DX centers in GaAlAs

E. Calleja, A. Gomez, E. Muñoz, and P. Cámara

Appl. Phys. Lett. 52, 1877 (1988); http://dx.doi.org/10.1063/1.99611 (3 pages) | Cited 34 times

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Deep level transient spectroscopy in Si‐ and Sn‐doped GaAlAs reveals a fine structure of the DX center thermal emission spectra under adequate filling pulse and sampling window times. This structure is reproducible in samples with Al mode fractions near 30% but it is not detectable in samples with 85% Al content. All resolved peaks of this fine structure have the same thermal emission energy but quite different capture cross section (σ∞n). This fact indicates that the origin of the fine structure and of the nonexponential behavior of the thermal emission processes is the discrete broadening of σ∞n due to the alloy effect.
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71.55.Eq III-V semiconductors

Novel method for measuring excimer laser ablation thresholds of polymers

P. E. Dyer, S. D. Jenkins, and J. Sidhu

Appl. Phys. Lett. 52, 1880 (1988); http://dx.doi.org/10.1063/1.99612 (3 pages) | Cited 22 times

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Conical features produced on excimer laser ablated polymers are shown to provide a sensitive technique for determining ablation thresholds. This has been applied to polyimide, polyethylene terephthalate, polyethylene, and nylon 66 ablated using the 157 nm vacuum ultraviolet F2 laser.
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79.20.Ds Laser-beam impact phenomena
81.05.Lg Polymers and plastics; rubber; synthetic and natural fibers; organometallic and organic materials
81.65.-b Surface treatments
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)

AlGaAs doping superlattices grown by molecular beam epitaxy

D. E. Ackley, H. Lee, N. Nouri, and C. Colvard

Appl. Phys. Lett. 52, 1883 (1988); http://dx.doi.org/10.1063/1.99613 (3 pages)

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AlGaAs doping superlattices (‘‘nipi structures’’) have been successfully grown in 30% AlGaAs by molecular beam epitaxy. Tunable photoluminescence (PL) as a function of incident laser intensity has been observed in samples with a wide range of intrinsic layer thicknesses over a temperature range from 2 to 120 K. Luminescence shifts as large as 230 meV were observed for a range of incident intensities of about 500. Low‐temperature PL spectra showed a weaker dependence of the peak energy on incident intensity for thicker spacer layers. This decrease in tuning rate can be associated with the reduced probability for tunneling transitions with increasing spacer thickness.
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78.66.Fd III-V semiconductors
78.66.Hf II-VI semiconductors
78.55.Cr III-V semiconductors
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

Capture of electrons and holes in quantum wells

Benoit Deveaud, Jagdeep Shah, T. C. Damen, and W. T. Tsang

Appl. Phys. Lett. 52, 1886 (1988); http://dx.doi.org/10.1063/1.99614 (3 pages) | Cited 19 times

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The capture of electrons and holes by quantum wells in multiple quantum well samples of InGaAs/InP is investigated using subpicosecond luminescence spectroscopy. For samples with thin barriers, quantum capture or carrier thermalization dominates. For thicker barriers (>500 Å), transport of carriers to the well dominates. We show that quantum capture time is <0.3 ps for holes and <1 ps for electrons. No significant dependence on well thickness is observed. Finally, Coulomb interaction between electrons and holes is shown to ‘‘trap’’ the electrons in unbound states in InGaAs before they are captured by the well.
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73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
73.61.Ey III-V semiconductors

High‐efficiency, one‐sun (22.3% at air mass 0; 23.9% at air mass 1.5) monolithic two‐junction cascade solar cell grown by metalorganic vapor phase epitaxy

B‐C. Chung, G. F. Virshup, and J. G. Werthen

Appl. Phys. Lett. 52, 1889 (1988); http://dx.doi.org/10.1063/1.99615 (3 pages) | Cited 8 times

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A high‐efficiency monolithic two‐junction solar cell consisting of an Al0.37Ga0.63As (Eg =1.93 eV) upper cell and a GaAs lower cell has been grown by metalorganic vapor phase epitaxy. Since both component cells have the n‐on‐p configuration, the unwanted p‐n junction has been eliminated with the use of metal‐interconnect contact during post‐growth processing. As a two‐terminal device, an efficiency of 22.3% has been achieved under 1 sun, air mass 0 illumination conditions, whereas an efficiency of 23.9% was obtained when the cascade cell was operated as a three‐terminal device under 1 sun, air mass 1.5 illumination. This result represents the highest 1 sun efficiency ever reported. The advantages of utilizing this multijunction solar cell for terrestrial and space applications are also described.
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84.60.Jt Photoelectric conversion
72.40.+w Photoconduction and photovoltaic effects

Stacking‐fault‐induced defect creation in SiO2 on Si(100)

M. Liehr, G. B. Bronner, and J. E. Lewis

Appl. Phys. Lett. 52, 1892 (1988); http://dx.doi.org/10.1063/1.99734 (3 pages) | Cited 9 times

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Decomposition of SiO2 films on Si(100) during ultrahigh‐vacuum anneal has been shown previously to be preceded, at low anneal temperatures, by electrical defect creation in metal‐oxide‐semiconductor structures. In this letter, the presence of stacking faults in a Si substrate is shown to be related to enhanced oxide decomposition during high‐temperature anneal. Decomposition is enhanced because of the creation of a larger number of nucleation centers for the formation of volatile SiO. These nucleation centers are the result of the metals gettered in the stacking faults close to the SiO2/Si interface.
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61.72.Bb Theories and models of crystal defects
68.35.Dv Composition, segregation; defects and impurities
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.72.Nn Stacking faults and other planar or extended defects

Bi‐Sr‐Ca‐Cu‐O superconductor system with critical temperatures of 80 and 107 K

K. Kugimiya, S. Kawashima, O. Inoue, and S. Adachi

Appl. Phys. Lett. 52, 1895 (1988); http://dx.doi.org/10.1063/1.99735 (2 pages) | Cited 9 times

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Critical temperatures (Tc) of 80 and 107 K are confirmed by resistivity and inductance measurements and also by the Meissner effect. X‐ray/electron diffraction and electron microscopy analyses on a single phase material of 80 K show that its structure is orthorhombic with a unit cell of a=5.407 Å, b=27.011 Å, c= 30.588 Å composed of a pseudotetragonal cell of a=b=5.41 Å. The pseudotetragonal cell size and cleavage behavior to very thin flakes strongly indicate that the oxide is basically a lamellar oxide of the Aurivillius phase type, i.e., a stacked layer structure of (Bi2O2)2+ sheets and distorted perovskite cell sheets.
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74.70.-b Superconducting materials other than cuprates
61.66.Fn Inorganic compounds
74.25.Sv Critical currents
74.62.Bf Effects of material synthesis, crystal structure, and chemical composition
74.78.Fk Multilayers, superlattices, heterostructures

Plasma polymerization for high Tc oxide superconductors

Shin’ichi Morohashi, Hirotaka Tamura, Akira Yoshida, and Shinya Hasuo

Appl. Phys. Lett. 52, 1897 (1988); http://dx.doi.org/10.1063/1.99736 (2 pages) | Cited 4 times

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Plasma polymerization using CHF3 gas, which prevents the degradation of high Tc oxide superconductors due to moisture and annealing, was developed. The resistive transitions of Y1Ba2Cu3Ox thin films, coated by plasma polymerization, did not change before and after soaking in 20 °C water for 60 min. In addition, the critical temperature of those films was unchanged after annealing at 200 °C for 30 min in air, and then soaking in 90 °C water for 10 min. We confirmed that the polymer film grown by this method was dense, and the Y1Ba2Cu3Ox film reacted with the fluorine at the interface using x‐ray photoelectron spectroscopy.
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82.35.-x Polymers: properties; reactions; polymerization
74.78.-w Superconducting films and low-dimensional structures
74.70.-b Superconducting materials other than cuprates
81.05.Je Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides)
81.65.-b Surface treatments

Low‐temperature x‐ray diffraction of the Y1Ba2Cu3O9−x oxide ceramic superconductor

Hua‐qing Yin, Yi‐mei Gao, Jia‐ju Du, Ben‐pei Chen, Jian‐yi Jiang, and Xiang Wang

Appl. Phys. Lett. 52, 1899 (1988); http://dx.doi.org/10.1063/1.99737 (2 pages) | Cited 13 times

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The change of the lattice parameter with temperature (82–320 K) of the single phase Y1Ba2Cu3O9−x superconductor has been investigated by x‐ray diffractometer. The experimental result shows that there exist two abrupt changes of lattice parameter at about 250 and 125 K separately in the curve of the lattice parameter versus temperature. But no change of structure symmetry was observed as shown by x‐ray diffraction. The abrupt change of lattice parameter at about 250 and 125 K may be associated to the position adjusting of oxygen atoms in oxide ceramic.
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74.70.-b Superconducting materials other than cuprates
61.66.Fn Inorganic compounds
74.25.Sv Critical currents
74.62.Bf Effects of material synthesis, crystal structure, and chemical composition

Structural phase transformation in the superconducting YLaxBa2−xCu3O7 compounds

T. C. Huang, Y. Tokura, J. B. Torrance, A. I. Nazzal, and R. Karimi

Appl. Phys. Lett. 52, 1901 (1988); http://dx.doi.org/10.1063/1.99738 (3 pages) | Cited 5 times

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An orthorhombic‐to‐tetragonal phase transformation in YLaxBa2−xCu3O7 has been observed as a function of x, but with the same oxygen concentration, from x‐ray powder diffraction data. Compounds with x≤0.37 have Tc in the 93–53 K range and are orthorhombic, while compounds with x≥0.45 have Tc≤42 K and are tetragonal. An analysis of the YLa0.6Ba1.4Cu3O6.99 diffraction pattern suggests that the tetragonal structure is closely related to those of the orthorhombic YBa2Cu3O7 and the tetragonal YBa2Cu3O6 with a partial substitution of La3+ ion on the Ba2+ site and a disorder of oxygen atoms at the midpoints of both a and b unit cell edges.
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74.70.-b Superconducting materials other than cuprates
64.70.K- Solid-solid transitions
61.66.Fn Inorganic compounds

Preparation, patterning, and properties of thin YBa2Cu3O7−δ films

J. W. C. de Vries, B. Dam, M. G. J. Heijman, G. M. Stollman, M. A. M. Gijs, C. W. Hagen, and R. P. Griessen

Appl. Phys. Lett. 52, 1904 (1988); http://dx.doi.org/10.1063/1.99739 (3 pages) | Cited 17 times

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High TC superconducting thin films were prepared on (100) SrTiO3 substrates by dc triode sputtering and subsequent annealing. In these films Hall‐bar structures having a width down to 5 μm were patterned using a reactive ion etching technique. Superconductivity above 77 K was observed. When compared with the original film there is only a small reduction in TC. The critical current density determined by electrical measurements is substantially reduced. On the other hand, the critical current density in the bulk of the grains as measured by the torque on a film is not reduced by the patterning process. It is suggested that superconductor‐normal metal‐superconductor junctions between the grains account for this difference.
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74.78.-w Superconducting films and low-dimensional structures
81.15.Cd Deposition by sputtering
81.05.Je Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides)
81.65.-b Surface treatments
74.70.-b Superconducting materials other than cuprates

Target presputtering effects on stoichiometry and deposition rate of Y‐Ba‐Cu‐O thin films grown by dc magnetron sputtering

T. I. Selinder, G. Larsson, U. Helmersson, P. Olsson, J.‐E. Sundgren, and S. Rudner

Appl. Phys. Lett. 52, 1907 (1988); http://dx.doi.org/10.1063/1.99740 (3 pages) | Cited 13 times

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Y‐Ba‐Cu‐O thin films have been grown from stoichiometric compound targets using dc magnetron sputtering. Initially, the film composition was strongly off‐stoichiometric and the deposition rate very low. However, after extensive presputtering, stoichiometric films, with respect to the metal content, were deposited at a rate of 2–2.5 Å/s. The long presputtering time (20–30 h) needed is due to a slowly changing oxygen content on the target surface. This is caused not only by preferential sputtering effects, but also by bulk diffusion in the target. The presputtering time is significantly decreased if the target is annealed in an argon atmosphere prior to use. Oxygen adsorbed on the target surface during venting of the chamber will also affect the process significantly.
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68.55.Nq Composition and phase identification
81.15.Cd Deposition by sputtering
74.70.-b Superconducting materials other than cuprates
74.78.-w Superconducting films and low-dimensional structures

Critical current densities in single‐crystal Bi2.2Sr2Ca0.8Cu2O8+δ

R. B. van Dover, L. F. Schneemeyer, E. M. Gyorgy, and J. V. Waszczak

Appl. Phys. Lett. 52, 1910 (1988); http://dx.doi.org/10.1063/1.99741 (3 pages) | Cited 34 times

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We report transport and magnetic measurements of critical current densities in single crystals of high Tc superconductors in the Bi‐Sr‐Ca‐Cu‐O system. Transport measurements of Jc were made using a pulse method, while a vibrating sample magnetometer was used to measure M‐H loops of oriented crystals in fields up to 15 kOe. Values for transport Jc in zero applied field are higher than those of Ba2YCu3O7 single crystals at comparable temperatures. Also we observe a strong magnetic field dependence for Jc at temperatures above ∼20 K.
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74.25.Sv Critical currents
74.25.N- Response to electromagnetic fields
74.70.-b Superconducting materials other than cuprates
74.25.Ha Magnetic properties including vortex structures and related phenomena

Fabrication of the Bi1Sr1Ca1Cu2Ox high Tc superconductor

M. M. Garland

Appl. Phys. Lett. 52, 1913 (1988); http://dx.doi.org/10.1063/1.99742 (2 pages) | Cited 7 times

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The high Tc superconductor Bi1Sr1Ca1Cu2Ox has been fabricated from a solid‐state reaction of SrCO3, CaCO3, Cu2O, and Bi. The onset temperature is found to be 120 K. A second phase is present with an onset of 90 K. Both phases are observed in ac susceptibility and resistance data. This compound appears to be more stable than Y1Ba2Cu3O7 in the presence of water.
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74.70.-b Superconducting materials other than cuprates
81.05.Je Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides)
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