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13 Aug 1990

Volume 57, Issue 7, pp. 643-734

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Efficient generation of ultrafast broadband radiation in a submillimeter liquid‐core waveguide

J. Y. Zhou, H. Z. Wang, and Z. X. Yu

Appl. Phys. Lett. 57, 643 (1990); http://dx.doi.org/10.1063/1.103619 (2 pages) | Cited 6 times

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An experimental investigation of picosecond laser propagation in a submillimeter liquid‐core waveguide is presented. It is observed that the pump is spectrally broadened towards its Stokes frequency upon passing through the waveguide and the spectral bandwidth is further extended by stimulated raman scattering. This stable ultrafast broadband radiation is shown to be enhanced due to the use of the waveguide.
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42.81.Dp Propagation, scattering, and losses; solitons
42.79.Gn Optical waveguides and couplers

Near‐infrared emission in a chemically excited oxygen system

S. Yoshida, T. Tokuda, K. Shimizu, K. Ogasawara, and T. Sawano

Appl. Phys. Lett. 57, 645 (1990); http://dx.doi.org/10.1063/1.103620 (2 pages) | Cited 3 times

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Near‐infrared emission has been observed in a chemically generated singlet oxygen system. Spectrum peaks observed at 1090, 1275, and 1550 nm appear to correspond to O2(1Δ)O2(3Σ) dimer transitions to ground state accompanied by vibrational changes. The experimental result suggests that the previously observed visible emission which accompanies the present infrared emission is also due to an excited oxygen dimer. The possibility of lasing at the infrared wavelengths is discussed.
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33.20.Ea Infrared spectra
82.35.-x Polymers: properties; reactions; polymerization
82.30.Cf Atom and radical reactions; chain reactions; molecule-molecule reactions
31.50.Df Potential energy surfaces for excited electronic states

Excimer laser direct writing of titanium lines on lithium niobate

R. Izquierdo, C. Lavoie, and M. Meunier

Appl. Phys. Lett. 57, 647 (1990); http://dx.doi.org/10.1063/1.104252 (3 pages) | Cited 5 times

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We have investigated the deposition of titanium lines from titanium tetrachloride (TiCl4) onto lithium niobate (LiNbO3). The deposition is induced using a KrF excimer laser (λ=248 nm). Our objective is the formation of titanium indiffused LiNbO3 optical waveguides. The titanium lines contain little chlorine ([Cl] <2 at. %) and are typically 20–100 nm thick, and 3–20 μm wide. We find that the process is controlled by photochemistry of TiCl4. However it is difficult, at this point, to detemine whether the gas or the adsorbed layer is the primary source of thin‐film growth.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
42.86.+b Optical workshop techniques
42.79.Gn Optical waveguides and couplers

Eye‐safe Nd:YAG laser

S. K. Wong, P. Mathieu, and P. Pace

Appl. Phys. Lett. 57, 650 (1990); http://dx.doi.org/10.1063/1.103621 (3 pages) | Cited 6 times

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We have demonstrated that a significant amount of laser energy can be extracted at 1.4444 μm from Nd:YAG at room temperature. The stimulated emission cross section at 1.4444 μm is not unduly small. More than 1 J of laser energy in the non‐Q‐switched mode and over 130 mJ with a pulse width of 85 ns full width at half maximum in the Q‐switched mode have been obtained. The 1.4444 μm laser has also been operated successfully at repetition rates up to 10 Hz at the 100 mJ/pulse level. Other lasing transitions at 1.064, 1.3187, 1.3381, 1.3572, and 1.4150 μm have also been observed.
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42.60.By Design of specific laser systems
42.55.Px Semiconductor lasers; laser diodes
42.55.Rz Doped-insulator lasers and other solid state lasers
42.60.Da Resonators, cavities, amplifiers, arrays, and rings

Femtosecond erbium‐doped optical fiber amplifier

Masataka Nakazawa, Kenji Kurokawa, Hirokazu Kubota, Kazunori Suzuki, and Yasuo Kimura

Appl. Phys. Lett. 57, 653 (1990); http://dx.doi.org/10.1063/1.104102 (3 pages) | Cited 22 times

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A gain of 9 dB has been obtained in an erbium‐doped optical fiber amplifier for input pulses with a peak power of 30 W, an average power of 30 μW (−15.2 dBm), and a pulse width of 260 fs. When the input peak power is increased in the soliton power regime, an adiabatic soliton narrowing occurs due to the optical gain. By increasing the pump power further, an optical gain enhanced soliton self‐frequency shift dominates, which is due to the excitation of high‐order soliton. Thus, soliton narrowing from 250 to 60 fs is observed.
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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
42.81.Gs Birefringence, polarization
42.79.Sz Optical communication systems, multiplexers, and demultiplexers

Infrared erasure of self‐organized χ(2) gratings in high germania content optical fibers

Yoshinori Hibino, Victor Mizrahi, George I. Stegeman, and Shoichi Sudo

Appl. Phys. Lett. 57, 656 (1990); http://dx.doi.org/10.1063/1.103603 (3 pages) | Cited 8 times

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We demonstrate that the self‐organized χ(2) grating in a high germania content optical fiber can be erased by prolonged exposure to 1.064 μm radiation only. The decay rate, which is proportional to the fourth power of the 1064 nm intensity, is attributed to two‐photon absorption of the second‐harmonic light generated in the fiber.
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42.81.Dp Propagation, scattering, and losses; solitons
42.81.Gs Birefringence, polarization
42.79.Dj Gratings
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation

Monitoring the performance of a semiconductor optical amplifier

N. K. Dutta, A. B. Piccirilli, M. S. Lin, and T. R. Halemane

Appl. Phys. Lett. 57, 659 (1990); http://dx.doi.org/10.1063/1.103604 (2 pages) | Cited 2 times

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Measurements of optical gain and spontaneous emission of optical amplifiers show that the latter is a good measure of the former. A device structure is fabricated where a photodetector is integrated next to the amplifier. A fraction of the spontaneous emission from the amplifier impinges on the photodetector in this device producing a photocurrent. The photodetector current is found to be a monotonic function of the amplifier gain. Hence, the photodetector output can be used to monitor the performance of the amplifier.
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07.60.-j Optical instruments and equipment
42.79.-e Optical elements, devices, and systems
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
85.60.-q Optoelectronic devices

Laser‐induced fluorescence measurements of transverse ion temperature in an electron cyclotron resonance plasma

E. A. Den Hartog, H. Persing, and R. Claude Woods

Appl. Phys. Lett. 57, 661 (1990); http://dx.doi.org/10.1063/1.103585 (3 pages) | Cited 51 times

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Laser‐induced fluorescence has been used to measure the Doppler profile of a transition in N+2 [the R18 component of the X2∑+g(ν = 0)⇒B2∑+u(ν = 0) band] in a pure N2 electron cyclotron resonance (ECR) plasma. The transverse ion temperature (Ti⊥) was determined from the measured width of the Doppler broadened transition. The measurements were made on axis, 41 cm downstream (‖B‖∼170 G) from the first electron cyclotron resonance. We found Ti⊥ decreased from 0.25 to 0.12 eV as the corresponding downstream neutral pressure increased from 0.5 to 4.0 mTorr. These results have important implications for the use of ECR devices for plasma etching, since Ti⊥ may determine the ultimate limit to the anisotropy of the etch.
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52.70.Kz Optical (ultraviolet, visible, infrared) measurements
52.80.Pi High-frequency and RF discharges
81.65.-b Surface treatments

SiO2 thin‐film deposition by excimer laser ablation from SiO target in oxygen atmosphere

E. Fogarassy, C. Fuchs, A. Slaoui, and J. P. Stoquert

Appl. Phys. Lett. 57, 664 (1990); http://dx.doi.org/10.1063/1.104253 (3 pages) | Cited 21 times

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Silicon dioxide thin films are deposited, for the first time, by reactive laser ablation from a silicon monoxide target in oxygen atmosphere, with a high‐power pulsed ArF (λ=193 nm) excimer laser. The specific influence of oxygen in the chamber during the laser processing on the stoichiometry and final properties of the oxide films deposited at ambient temperature is demonstrated.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)

Comparison of the selective adsorption and reactivity behavior of WF6 and TaF5 on SiO2 and polyimide surfaces

F. R. McFeely, L. J. Terminello, and S. P. Kowalczyk

Appl. Phys. Lett. 57, 667 (1990); http://dx.doi.org/10.1063/1.104254 (3 pages) | Cited 6 times

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The initial stages of WF6 and TaF5 adsorption on SiO2 and polyimide surfaces were investigated by photoelectron spectroscopy. WF6 selectively adsorbs on Si relative to SiO2 and polyimide, while TaF5 exhibited nonselective adsorption behavior. This trend is explained by differences in molecular structure and suggests a general basis for predicting selective deposition.
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68.43.-h Chemisorption/physisorption: adsorbates on surfaces
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Planar InP/InGaAs avalanche photodetectors with partial charge sheet in device periphery

L. E. Tarof, D. G. Knight, K. E. Fox, C. J. Miner, N. Puetz, and H. B. Kim

Appl. Phys. Lett. 57, 670 (1990); http://dx.doi.org/10.1063/1.103586 (3 pages) | Cited 21 times

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A novel planar separate absorption, charge sheet, grading and multiplication avalanche photodiode (APD) structure incorporating a partial charge sheet in the device periphery is described, which allows for straightforward fabrication of APD devices without the use of guard rings. Metalorganic chemical vapor deposition grown, Zn‐diffused InP/InGaAs APD devices have been fabricated. High dc gains well in excess of 100 and a low primary dark current of 0.1 nA at 0.99 of the breakdown voltage VB have been measured for a 40‐μm‐diam device. The receiver sensitivity for a bit error rate of 10−9 at a bit rate of 400 Mbit/s was −41 dBm. The −3 dB electrical bandwidth was 2.5 GHz, and the gain‐bandwidth product was 30 GHz.
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85.60.Gz Photodetectors (including infrared and CCD detectors)
85.30.Mn Junction breakdown and tunneling devices (including resonance tunneling devices)
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Effect of polymer matrices on hopping charge transport in molecularly doped polymers

Yoshihiko Kanemitsu and Jiro Einami

Appl. Phys. Lett. 57, 673 (1990); http://dx.doi.org/10.1063/1.103587 (3 pages) | Cited 22 times

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We have studied the effect of polymer matrices on time‐of‐flight (TOF) photocurrent pulse shape and the drift mobility of holes in polymers doped with 2‐(p‐dipropylaminophenyl)‐4‐(p‐dimethylaminophenyl)‐5‐(o‐chlorophenyl)‐1, 3‐oxazole in order to understand the nature of hopping charge transport in molecularly doped polymers (MDPs). The TOF pulse shapes in oxazole‐doped polymers are classed into two groups: near rectangular or dispersive shapes. The drift mobility of holes in MDPs exhibiting near‐rectangular TOF shape is large compared with that exhibiting dispersive. Moreover, the drift mobility of holes depends on the dielectric constant and the glass transition temperature of polymers. These results show that the polarization and phonon mode of polymers play an important role in hopping charge transport in MDPs.
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72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping
72.40.+w Photoconduction and photovoltaic effects
73.61.Ng Insulators

Interface impurities of low‐temperature (900 °C) deposited Si epitaxial films prepared by HF treatments

Akihiro Miyauchi, Yousuke Inoue, Takaya Suzuki, and Mikio Akiyama

Appl. Phys. Lett. 57, 676 (1990); http://dx.doi.org/10.1063/1.103588 (2 pages) | Cited 8 times

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Impurities at the interfaces of HF‐treated Si (100) substrates and Si films prepared by low‐temperature (900 °C) chemical vapor deposition using SiH2 Cl2 were measured by secondary‐ion mass spectroscopy. Si substrates were prepared by 49% HF, 5% HF, and 0.05% HF acid solutions and loaded into the growth chamber without a water rinse. Carbon, fluorine, oxygen and chlorine were detected at the interfaces for 49% HF and 0.05% HF treated substrates, but they were not detected for 5% HF‐treated samples. Desorption of the contaminants appeared to be sensitively related to a difference in chemical states of the HF‐treated surfaces.
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81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.15.Kk Vapor phase epitaxy; growth from vapor phase
82.20.Hf Product distribution
81.10.Bk Growth from vapor

Enhanced etching of silicon in CF4‐O2‐N2 plasma

V. Premachandran

Appl. Phys. Lett. 57, 678 (1990); http://dx.doi.org/10.1063/1.103589 (2 pages) | Cited 1 time

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It is shown that a threefold increase in the etch rate of silicon can be achieved with the addition of 1% of nitrogen into the CF4‐O2 plasma. An increase in the atomic fluorine concentration is shown to be responsible for this enhancement in the etch rate.
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81.65.-b Surface treatments
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces

Heavily carbon‐doped GaAlAs grown by vacuum chemical epitaxy

M. M. G. de Carvalho, C. L. Barreto, M. A. Cotta, and K. M. Ito

Appl. Phys. Lett. 57, 680 (1990); http://dx.doi.org/10.1063/1.103590 (3 pages) | Cited 3 times

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Heavily p‐doped GaAlAs layers have been grown on GaAs substrates by vacuum chemical epitaxy (VCE), using trimethylaluminum (TMA) as an aluminum source. Triethylgallium (TEG) and arsine were used as gallium and arsenic sources, respectively. Net carrier concentrations in the range 5×1019–2×1020 cm−3 and mobilities of ≂30–40 cm2/V s have been achieved. GaAlAs layers grown with triisobutylaluminum (TIBAl) as aluminum source have shown residual concentrations almost three orders of magnitude smaller, thus indicating a greater carbon incorporation associated to the use of TMA. The residual dopant concentration can be reduced by using a higher AsH3 flow or introducing H2 in a VCE reactor during growth, due to the easier methyl removal in these conditions.
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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.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

Experimental observation of negative differential resistance from an InAs/GaSb interface

D. A. Collins, E. T. Yu, Y. Rajakarunanayake, J. R. Söderström, D. Z.‐Y. Ting, D. H. Chow, and T. C. McGill

Appl. Phys. Lett. 57, 683 (1990); http://dx.doi.org/10.1063/1.103591 (3 pages) | Cited 25 times

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We have observed negative differential resistance at room temperature from devices consisting of a single interface between n‐type InAs and p‐type GaSb. InAs and GaSb have a type II staggered band alignment; hence, the negative differential resistance arises from the same mechanism as in a p+‐n+ tunnel diode. Room‐temperature peak current densities of 8.2×104 A/cm2 and 4.2×104 A/cm2 were measured for structures with and without undoped spacer layers at the heterointerface, respectively.
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85.30.Mn Junction breakdown and tunneling devices (including resonance tunneling devices)
73.40.Lq Other semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
73.40.Gk Tunneling

Columnar epitaxy of PtSi on Si (111)

R. W. Fathauer, Q. F. Xiao, Shin Hashimoto, and C. W. Nieh

Appl. Phys. Lett. 57, 686 (1990); http://dx.doi.org/10.1063/1.103592 (3 pages) | Cited 7 times

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Columnar grains of PtSi surrounded by high quality epitaxial silicon are obtained by ultrahigh vacuum codeposition of Si and Pt in an 8:1 ratio on Si(111) substrates heated to 610–810 °C. The areal density of columns varies from 120 to 3.8 μm−2, and layers with thicknesses from 100 nm to 1 μm have been demonstrated. This result is similar to that found previously for CoSi2 (a nearly lattice‐matched cubic‐fluorite crystal) on Si(111), in spite of the orthorhombic structure of PtSi. The PtSi grains are also epitaxial and have one of three variants of the relation defined by PtSi(010)//Si(111), with PtSi[001]//Si〈110〉.
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81.15.Kk Vapor phase epitaxy; growth from vapor phase
68.55.-a Thin film structure and morphology

Surface kinetics of chemical beam epitaxy of GaAs

B. W. Liang and C. W. Tu

Appl. Phys. Lett. 57, 689 (1990); http://dx.doi.org/10.1063/1.103593 (3 pages) | Cited 5 times

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A new kinetic model for chemical beam epitaxy of GaAs using triethylgallium and arsine is proposed. Both group III and group V species are equally important in the surface reactions. This model can fit experimental data very well. Various aspects of the growth rate as a function of substrate temperature, triethylgallium and arsine flow rates are examined.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Reflection high‐energy electron diffraction studies of the growth of strained InxGa1−xAs on GaAs substrate by migration‐enhanced epitaxy

Y. C. Chen, P. K. Bhattacharya, and J. Singh

Appl. Phys. Lett. 57, 692 (1990); http://dx.doi.org/10.1063/1.103594 (3 pages) | Cited 1 time

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Reflection high‐energy electron diffraction oscillations have been studied during the growth of strained InxGa1−xAs on GaAs by molecular beam epitaxy and migration‐enhanced epitaxy. The oscillations decay rapidly for x≳0.2 during molecular beam epitaxy, while they persist for a long while during migration‐enhanced epitaxy. We believe that the altered surface reconstruction pattern in the latter case changes the growth mode from three‐dimensional to a near perfect two‐dimensional mode for high strain values. Using migration‐enhanced epitaxy, we demonstrate improved channel mobility and performance of GaAs‐based modulation‐doped field‐effect transistors and narrower linewidths in the low‐temperature excitonic photoluminescence of In0.1Ga0.9As/Al0.3Ga0.7As quantum wells.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.35.Fx Diffusion; interface formation
61.05.jh Low-energy electron diffraction (LEED) and reflection high-energy electron diffraction (RHEED)

Use of tertiarybutylarsine in the fabrication of GaAs/AlGaAs quantum wells and quantum well lasers

S. G. Hummel, C. A. Beyler, Y. Zou, P. Grodzinski, and P. D. Dapkus

Appl. Phys. Lett. 57, 695 (1990); http://dx.doi.org/10.1063/1.103595 (3 pages) | Cited 12 times

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Tertiarybutylarsine was used in the growth of GaAs and AlGaAs by metalorganic chemical vapor deposition over a range of compositions and V/III ratios. GaAs layers were obtained with both n‐ and p‐type background carrier concentrations in the low 1014 cm−3 range. AlGaAs was grown at 20, 30, and 50% compositions, and photoluminescence of the Al0.2Ga0.8As indicates high quality material with full width half maximum (FWHM) values of the peaks being comparable to arsine‐grown AlGaAs. High quality multiple Al0.3Ga0.7As/GaAs quantum wells of various widths produced photoluminescence spectra with FWHM values comparable to arsine‐grown samples. Minority‐carrier lifetimes as long as 400 ns were measured for a heterostructure of 0.5 μm GaAs with Al0.3Ga0.7As barrier layers. Graded index separate confinement heterostructure lasers were fabricated, and broad‐ area test results of these devices produced threshold current densities as low as 186 A/cm2.
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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.)
72.80.Ey III-V and II-VI semiconductors
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths

Stretched exponential illumination time dependence of positive charge and spin generation in amorphous silicon nitride

J. Kanicki, M. Sankaran, A. Gelatos, M. S. Crowder, and E. D. Tober

Appl. Phys. Lett. 57, 698 (1990); http://dx.doi.org/10.1063/1.104255 (3 pages) | Cited 18 times

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We report for the first time on the stretched exponential time dependence of positive charge and spin generated by subband‐gap ultraviolet illumination in gate‐quality nitrogen‐rich amorphous silicon nitride films. We have found that a stretched exponential function, which characterizes dispersive charge transport in silicon nitride, gives the best description of our experimental results. We also propose a mechanism which we believe is responsible for the creation of the positive charge and spin in the amorphous silicon nitride films.
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61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
72.40.+w Photoconduction and photovoltaic effects

Excimer laser induced etching of InP

V. M. Donnelly and T. R. Hayes

Appl. Phys. Lett. 57, 701 (1990); http://dx.doi.org/10.1063/1.103596 (3 pages) | Cited 7 times

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We report 193 nm ArF excimer laser induced etching of InP in Cl2. Etching occurs by desorption of an In‐chloride layer, as evidenced by an etch rate which increases linearly with laser repetition rate and is nearly pressure independent between 2 and 50 mTorr Cl2. At substrate temperatures near 150 °C, the etch rate increases above a ‘‘threshold’’ fluence of 0.02 J/cm2 and saturates at 2.3 Å/pulse by ∼0.12 J/cm2, corresponding to nearly one monolayer of InP removed per laser pulse. On samples masked with SiO2 stripes, etched surfaces were smooth, with little or no undercutting of the mask edge. Sidewalls on etched features slope out at a ∼45° angle. Etching mechanisms and implications for in situ processing are discussed.
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81.65.-b Surface treatments
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)

Picosecond photoluminescence excitation spectroscopy of GaAs/AlGaAs quantum wells

M. R. Freeman, D. D. Awschalom, and J. M. Hong

Appl. Phys. Lett. 57, 704 (1990); http://dx.doi.org/10.1063/1.103597 (3 pages) | Cited 8 times

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A synchronous pair of pulsed dye lasers is used to obtain continuous photoexcitation energy spectra of quantum well luminescence at fixed time delays following carrier generation, with picosecond time resolution. A measurement of the energy‐dependent initial luminescence polarization of photoexcited carriers in GaAs/AlGaAs quantum wells, from a pulsed optical pumping experiment, is presented as an illustration of the technique.
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78.55.Cr III-V semiconductors
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
78.47.-p Spectroscopy of solid state dynamics

Tunneling spectroscopic study of finite superlattices

R. J. Aggarwal, M. A. Reed, W. R. Frensley, Y.‐C. Kao, and J. H. Luscombe

Appl. Phys. Lett. 57, 707 (1990); http://dx.doi.org/10.1063/1.103598 (3 pages) | Cited 8 times

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We present a tunneling density of states study of the transition from a superlattice miniband to a sequential coupled well structure. We have observed by tunneling spectroscopy the eigenstates of a finite superlattice system far below the Stark localization threshold. The transition from an indistinguishable miniband to a coupled well structure is experimentally found to be 2.5 meV ≤W(miniband width)/n(♯ periods) ≤10.5 meV.
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73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
73.20.Fz Weak or Anderson localization

Possible presence of 2234 phase with Tc(zero) of 95 K in a Bi‐Pb‐Sb‐Sr‐Ca‐Cu‐O ceramic

Hong Wang, Xiaolin Wang, Shuxia Shang, Zhuo Wang, Zhikuan Lu, and Minhua Jiang

Appl. Phys. Lett. 57, 710 (1990); http://dx.doi.org/10.1063/1.104286 (2 pages) | Cited 5 times

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Samples of Bi1.84Pb0.34Sb0.1Sr2Ca2Cu3Oy ceramic were prepared by a direct sintering and air quenching method. A new phase with Tc(zero) of 95 K is detected inside multiphased samples by resistivity and susceptibility measurements. Powder x‐ray diffraction analysis indicates that the structure is orthorhombic with cell parameters a=5.41 Å, b=5.44 Å, c=43.35 Å. The (Bi, Pb)2Sr2Ca3Cu4Oy composition is determined by x‐ray energy dispersion analysis.
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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
61.66.Fn Inorganic compounds
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