APL Nameplate
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

6 May 2002

Volume 80, Issue 18, pp. 3247-3450

Page 1 of 3 Pages Next Page | Jump to Page
back to top
RSS Feeds

Beam steering in waveguide arrays

T. Pertsch, T. Zentgraf, U. Peschel, A. Bräuer, and F. Lederer

Appl. Phys. Lett. 80, 3247 (2002); http://dx.doi.org/10.1063/1.1476720 (3 pages) | Cited 18 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We demonstrate that highly efficient beam steering and switching can be achieved in thermo-optic waveguide arrays. For a given initial excitation, we find the position of the output field to depend on the transverse temperature gradient. By changing this gradient, we manage to steer the beam across the entire array. Diffractive spreading is almost suppressed and the beam retains its initial shape. © 2002 American Institute of Physics.
Show PACS
42.79.Gn Optical waveguides and couplers
42.65.Pc Optical bistability, multistability, and switching, including local field effects
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation

Interferential coupling effect on the whispering-gallery mode lasing in a double-layered microcylinder

Hee-Jong Moon and Kyungwon An

Appl. Phys. Lett. 80, 3250 (2002); http://dx.doi.org/10.1063/1.1476399 (3 pages) | Cited 18 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Enhanced mode selection through a strong interferential coupling effect was observed in a double-layered cylindrical microcavity laser. The coupling was induced by partial reflection and recombination with refracted light on the internal circular boundary of the fused silica capillary tube, filled with a dye-doped liquid having lower reflective index than that of fused silica. The observed interference period agreed well with the prediction by a ray-optic model. © 2002 American Institute of Physics.
Show PACS
42.55.Sa Microcavity and microdisk lasers
42.55.Mv Dye lasers
42.25.Hz Interference

Mode identification in spherical microcavities doped with quantum dots

B. Möller, M. V. Artemyev, U. Woggon, and R. Wannemacher

Appl. Phys. Lett. 80, 3253 (2002); http://dx.doi.org/10.1063/1.1475364 (3 pages) | Cited 19 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Using imaging spectroscopy at the diffraction limit, a polarization-sensitive mode mapping allows the experimental identification of transverse electric and transverse magnetic modes for spherical microcavities. The method is applied to microspheres surface covered by CdSe quantum dots. A theoretical estimate of the minimum mode volume excited by a single, anisotropic quantum dot is given with Q/V larger than 1000 μm−3 for the parameters of the experimentally studied microcavities. © 2002 American Institute of Physics.
Show PACS
78.67.Hc Quantum dots
78.40.Fy Semiconductors
42.55.Px Semiconductor lasers; laser diodes
42.50.-p Quantum optics

Infrared electroluminescence from an organic ionic dye containing no rare-earth ions

Hiroyuki Suzuki

Appl. Phys. Lett. 80, 3256 (2002); http://dx.doi.org/10.1063/1.1476711 (3 pages) | Cited 23 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This paper reports the electroluminescence (EL) characteristics of a single-layer light-emitting diode (LED) with an organic functional layer, which is composed of an organic ionic emissive dye, IR1051, an electron transporting material, 2-(4-biphenylyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole, and poly(N-vinylcarbazole). The LED exhibits IR EL in the 0.9–1.5 μm range, which is ascribable to IR1051 with reference to steady-state absorption and photoluminescence measurements. The present study demonstrates a class of IR EL materials containing no rare earth ions and compatible with silicon-based photocircuits. © 2002 American Institute of Physics.
Show PACS
78.66.Qn Polymers; organic compounds
78.60.Fi Electroluminescence
85.60.Jb Light-emitting devices
78.55.Kz Solid organic materials

Fiber Bragg gratings with enhanced thermal stability

Gilberto Brambilla and Harvey Rutt

Appl. Phys. Lett. 80, 3259 (2002); http://dx.doi.org/10.1063/1.1475366 (3 pages) | Cited 11 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Gratings written in tin-doped silica fibers by using a 248 nm excimer laser exhibit extremely high thermal stability. Isothermal measurements up to 1100 K demonstrate significant advantages over conventional fiber gratings. Extrapolations from experimental data indicated that gratings operating at 500 K for ten years will retain more than 99% of the initial strength. © 2002 American Institute of Physics.
Show PACS
42.79.Dj Gratings
42.81.-i Fiber optics

Advanced InAs/GaSb superlattice photovoltaic detectors for very long wavelength infrared applications

Y. Wei, A. Gin, M. Razeghi, and G. J. Brown

Appl. Phys. Lett. 80, 3262 (2002); http://dx.doi.org/10.1063/1.1476395 (3 pages) | Cited 42 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on the temperature dependence of the photoresponse of very long wavelength infrared type-II InAs/GaSb superlattice based photovoltaic detectors grown by molecular-beam epitaxy. The detectors had a 50% cutoff wavelength of 18.8 μm and a peak current responsivity of 4 A/W at 80 K. A peak detectivity of 4.5×1010 cm Hz1/2/W was achieved at 80 K at a reverse bias of 110 mV. The generation–recombination lifetime was 0.4 ns at 80 K. The cutoff wavelength increased very slowly with increasing temperature with a net shift from 20 to 80 K of only 1.2 μm. © 2002 American Institute of Physics.
Show PACS
85.60.Gz Photodetectors (including infrared and CCD detectors)
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Raster-scan imaging with normal-incidence, midinfrared InAs/GaAs quantum dot infrared photodetectors

A. D. Stiff-Roberts, S. Chakrabarti, S. Pradhan, B. Kochman, and P. Bhattacharya

Appl. Phys. Lett. 80, 3265 (2002); http://dx.doi.org/10.1063/1.1476387 (3 pages) | Cited 14 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We demonstrate normal incidence infrared imaging with quantum dot infrared photodetectors using a raster-scan technique. The device heterostructure, containing multiple layers of InAs/GaAs self-organized quantum dots, were grown by molecular-beam epitaxy. Individual devices have been operated at temperatures as high as 150 K and, at 100 K, are characterized by λpeak = 3.72 μm, Jdark = 6×10−10 A/cm2 for a bias of 0.1 V, and D∗ = 2.94×109 cm Hz1/2/W at a bias of 0.2 V. Raster-scan images of heated objects and infrared light sources were obtained with a small (13×13) interconnected array of detectors (to increase the photocurrent) at 80 K. © 2002 American Institute of Physics.
Show PACS
78.67.Hc Quantum dots
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors
85.60.Gz Photodetectors (including infrared and CCD detectors)

Monolithic integration of near-infrared Ge photodetectors with Si complementary metal–oxide–semiconductor readout electronics

Gianlorenzo Masini, Valentino Cencelli, Lorenzo Colace, Francesco De Notaristefani, and Gaetano Assanto

Appl. Phys. Lett. 80, 3268 (2002); http://dx.doi.org/10.1063/1.1477267 (3 pages) | Cited 15 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Using a low-temperature technology for polycrystalline Ge deposition, we report on the monolithic integration of an array of near-infrared Ge photodiodes on Si complementary metal–oxide–semiconductor (CMOS) electronics. The integrated microsystem consists of a linear array of 120×120 μm2 pixels, an analog CMOS multiplexer and a transimpedance amplifier. The resulting photoresponse covers the near-infrared up to 1.6 μm. © 2002 American Institute of Physics.
Show PACS
85.60.Dw Photodiodes; phototransistors; photoresistors
85.60.Gz Photodetectors (including infrared and CCD detectors)
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors
85.30.Tv Field effect devices

Light-controllable room temperature negative differential resistance in deep-trench type nitride–oxide tunneling device and its applications

Fen Chen, Baozhen Li, and Kai D Feng

Appl. Phys. Lett. 80, 3271 (2002); http://dx.doi.org/10.1063/1.1476959 (3 pages) | Cited 2 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This study presents the room-temperature operation of deep-trench type nitride–oxide metal–insulator–semiconductor three-terminal tunneling devices which were fabricated by a standard metal–oxide–semiconductor process. It is instructive to observe a photoinduced N-type negative differential resistance (NDR) with a high peak-to-valley current ratio for device operated under negative polysilicon node bias under tungsten lamp illumination. An explanation was provided for the NDR phenomenon with proper three-terminal biasing. The sudden current drop under light illumination was caused by the sudden reduction of the two-carrier conduction due to Esaki band-to-band tunneling. The NDR amplitude could be modulated by light intensity. The position of the NDR current peak was tunable at different voltages with different p-well biases. The optoelectronic response of nitride–oxide devices we investigate here may open an application window for the nitride–oxide system in silicon-based optoelectronic integrated circuits, wireless communications, and future quantum devices. © 2002 American Institute of Physics.
Show PACS
85.60.Bt Optoelectronic device characterization, design, and modeling
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
85.30.Mn Junction breakdown and tunneling devices (including resonance tunneling devices)

Intersubband absorption performed on p-type modulation-doped Si0.2Ge0.8/Si quantum wells grown on Si0.5Ge0.5 pseudosubstrate

L. Diehl, H. Sigg, G. Dehlinger, D. Grützmacher, E. Müller, U. Gennser, I. Sagnes, T. Fromherz, Y. Campidelli, O. Kermarrec, D. Bensahel, and J. Faist

Appl. Phys. Lett. 80, 3274 (2002); http://dx.doi.org/10.1063/1.1476723 (3 pages) | Cited 15 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present intersubband absorption measurements performed on p-type quasistrain-compensated modulation-doped Si0.2Ge0.8/Si quantum wells grown on Si0.5Ge0.5 pseudosubstrates. Several intersubband absorption peaks are observed up to room temperature. A strong confinement shift of the resonance occuring between the ground and the first excited heavy hole states has been observed, with the absorption peak shifting from λ = 5.3 μm to as short as 3.8 μm. Excellent overall agreement with a 6 band k⋅p calculation is obtained, proving the accuracy of recently predicted values of band offsets. © 2002 American Institute of Physics.
Show PACS
78.67.De Quantum wells
73.21.Fg Quantum wells
78.66.Db Elemental semiconductors and insulators
78.66.Li Other semiconductors
71.15.Qe Excited states: methodology

1.3 μm InAs quantum dot laser with To = 161 K from 0 to 80 °C

O. B. Shchekin and D. G. Deppe

Appl. Phys. Lett. 80, 3277 (2002); http://dx.doi.org/10.1063/1.1476708 (3 pages) | Cited 157 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Data are presented on the influence of p-type modulation doping on the gain characteristics of 1.3 μm InAs quantum dot lasers. The improvement in optical gain leads to very high characteristic temperatures for the lasing threshold that reach 161 K in the temperature range between 0 and 80 °C. 1.3 μm ground state lasing is obtained up to a temperature of 167 °C. © 2002 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.60.By Design of specific laser systems
85.35.Be Quantum well devices (quantum dots, quantum wires, etc.)
73.21.La Quantum dots

Hybrid time-resolved spectroscopic system for evaluating laser material using a table-top-sized, low-jitter, 3-MeV picosecond electron-beam source with a photocathode

Yuji Suzuki, Toshimasa Kozeki, Shingo Ono, Hidetoshi Murakami, Hideyuki Ohtake, Nobuhiko Sarukura, Terunobu Nakajyo, Fumio Sakai, and Yasushi Aoki

Appl. Phys. Lett. 80, 3280 (2002); http://dx.doi.org/10.1063/1.1476384 (3 pages) | Cited 3 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Hybrid time-resolved spectroscopy of laser media comparing electron-beam excitation and optically excited cases is performed using a newly developed, table-top-sized, low-jitter, 3-MeV picosecond electron-beam source with a photocathode. The properties of an electron-beam-pumped Ce3+:LiCaAlF6 (Ce:LiCAF) ultraviolet laser medium significant differ from those of an optically pumped medium. © 2002 American Institute of Physics.
Show PACS
07.60.Rd Visible and ultraviolet spectrometers
42.55.Rz Doped-insulator lasers and other solid state lasers

Two-section InGaN multiple-quantum-well laser diode with integrated electroabsorption modulator

Michael Kneissl, Thomas L. Paoli, Peter Kiesel, David W. Treat, Mark Teepe, Naoko Miyashita, and Noble M. Johnson

Appl. Phys. Lett. 80, 3283 (2002); http://dx.doi.org/10.1063/1.1477270 (3 pages) | Cited 15 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Q-switching is demonstrated in a two-section InGaN multiple-quantum-well (MQW) laser diode consisting of an electroabsorption modulator and amplifier (gain) section. The modulator and gain sections are optically coupled and share the same InGaN MQW active region, but they are electrically separated by a narrow dry-etched trench. Applying a reverse bias voltage to the modulator section controls the absorption in the modulator portion of the device by compensating the piezoelectric field in the InGaN quantum wells. Changes in the absorption coefficient as large as 5000 cm−1 were realized with a moderate reverse bias of 7.2 V. By forward biasing, the amplifier section at a constant current of 225 mA and by controlling the reverse bias modulator voltage, the output power of the two-section laser diode could be switched between <0.5 mW (off state) and more than 3 mW (on state) with a laser emission wavelength near 401 nm. © 2002 American Institute of Physics.
Show PACS
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
42.79.Hp Optical processors, correlators, and modulators
85.35.Be Quantum well devices (quantum dots, quantum wires, etc.)
42.82.Gw Other integrated-optical elements and systems
42.60.Fc Modulation, tuning, and mode locking

Near field imaging with negative dielectric constant lenses

J. T. Shen and P. M. Platzman

Appl. Phys. Lett. 80, 3286 (2002); http://dx.doi.org/10.1063/1.1471933 (3 pages) | Cited 60 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A recent analysis by Pendry [J. B. Pendry, Phys. Rev. Lett. 85, 3966 (2000)] shows that a dielectric slab with a dielectric constant ϵ = −1 can produce a perfect image in the electrostatic limit (c→∞), independent of the permeability μ, and therefore is a perfect lens. Here we include retardation effects and show how distance and dissipation make the lens no longer perfect. Nevertheless we conclude that very significant improvements over conventional near field imaging may be obtained in the microwave regime. © 2002 American Institute of Physics.
Show PACS
42.30.Wb Image reconstruction; tomography
42.79.Bh Lenses, prisms and mirrors

Tunable diode-pumped continuous-wave Cr2+:ZnSe laser

Evgeni Sorokin and Irina T. Sorokina

Appl. Phys. Lett. 80, 3289 (2002); http://dx.doi.org/10.1063/1.1479214 (3 pages) | Cited 19 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A midinfrared broadly tunable around 2.5 μm room-temperature continuous-wave diode-pumped Cr:ZnSe laser is reported. The laser is tunable over 350 nm and delivers up to 70 mW of the output radiation at 460 mW of the absorbed pump power and 17.5% slope efficiency. We observe the analog of the optical switching process, where the laser output is strongly modulated by only a few milliwatts of the visible radiation. © 2002 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.Fc Modulation, tuning, and mode locking
back to top
RSS Feeds

Initiation and evolution of phase separation in heteroepitaxial InAlAs films

B. Shin, A. Lin, K. Lappo, R. S. Goldman, M. C. Hanna, S. Francoeur, A. G. Norman, and A. Mascarenhas

Appl. Phys. Lett. 80, 3292 (2002); http://dx.doi.org/10.1063/1.1476386 (3 pages) | Cited 12 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have investigated the initiation and evolution of phase separation in heteroepitaxial InAlAs films. In misfit-free InAlAs layers, cross-sectional scanning tunneling microscopy (XSTM) reveals the presence of isotropic nanometer-sized clusters. For lattice-mismatched InAlAs layers with 1.2% misfit, quasiperiodic contrast modulations perpendicular to the growth direction are apparent. Interestingly, these lateral modulations are apparently initiated within the first few bilayers of film growth, and both the amplitude and wavelength of the modulations increase with film thickness. The saturation value of the modulation wavelength determined from XSTM coincides with the lateral superlattice period determined from (002) x-ray reciprocal space maps, suggesting that the lateral modulation wavelength represents a periodic composition variation. Together, these results suggest that phase separation in the heteroepitaxial InAlAs thin-film system is a misfit-driven kinetic process initiated by random compositional nonuniformities, which later develop into coupled compositional and surface morphological variations. © 2002 American Institute of Physics.
Show PACS
68.55.Nq Composition and phase identification
64.75.-g Phase equilibria
68.37.Ef Scanning tunneling microscopy (including chemistry induced with STM)

Schwoebel-Ehrlich barrier: from two to three dimensions

S. J. Liu, Hanchen Huang, and C. H. Woo

Appl. Phys. Lett. 80, 3295 (2002); http://dx.doi.org/10.1063/1.1475774 (3 pages) | Cited 43 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The Schwoebel-Ehrlich barrier—the additional barrier for an adatom to diffuse down a surface step—dictates the growth modes of thin films. The conventional concept of this barrier is two dimensional (2D), with the surface step being one monolayer. We propose the concept of a three-dimensional (3D) Schwoebel-Ehrlich barrier, and identify the 2D to 3D transition, taking aluminum as a prototype and using the molecular statics method. Our results show that: (1) substantial differences exist between the 2D and 3D barriers; (2) the transition completes in four monolayers; and (3) there is a major disparity in the 3D barriers between two facets; further, alteration of this disparity using surfactants can lead to the dominance of surface facet against thermodynamics. © 2002 American Institute of Physics.
Show PACS
68.43.Jk Diffusion of adsorbates, kinetics of coarsening and aggregation
68.35.Md Surface thermodynamics, surface energies
68.35.B- Structure of clean surfaces (and surface reconstruction)

Nondestructive defect delineation in SiC wafers based on an optical stress technique

Xianyun Ma, Mathew Parker, and Tangali S. Sudarshan

Appl. Phys. Lett. 80, 3298 (2002); http://dx.doi.org/10.1063/1.1469659 (3 pages) | Cited 12 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The potential of using the optical stress technique to delineate the various defects in silicon carbide (SiC) wafers has been fully demonstrated. The observed defects include micropipes, dislocations, stress striations, grain boundary or dislocation walls, and regions of polytype nonuniformity. Revealed dislocation density is in the range 104–105 cm−2. © 2002 American Institute of Physics.
Show PACS
61.72.Ff Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.)
61.72.-y Defects and impurities in crystals; microstructure
61.72.Mm Grain and twin boundaries

Study of photoluminescence at 3.310 and 3.368 eV in GaN/sapphire(0001) and GaN/GaAs(001) grown by liquid-target pulsed-laser deposition

K. W. Mah, J.-P. Mosnier, E. McGlynn, M. O. Henry, D. O’Mahony, and J. G. Lunney

Appl. Phys. Lett. 80, 3301 (2002); http://dx.doi.org/10.1063/1.1476058 (3 pages) | Cited 8 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Epitaxial GaN films of thickness ∼1 μm have been grown on sapphire(0001) and GaAs(001) substrates using the liquid-target pulsed-laser-deposition technique in a 5 Torr nitrogen atmosphere. Detailed x-ray diffraction and photoluminescence studies were carried out for both types of samples. Significantly enhanced low-temperature photoluminescence emissions at 3.368 eV (I3) and 3.310 eV (I4) were observed for the material deposited on a GaAs(001) substrate at ∼800 °C. We propose a model to explain the emission mechanism for both lines in which the electrons and holes are confined in cubic inclusions within the hexagonal material, analogously to a type-I quantum well. © 2002 American Institute of Physics.
Show PACS
78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors
81.05.Ea III-V semiconductors
81.15.Fg Pulsed laser ablation deposition

Quantum chemical study of the mechanism of aluminum oxide atomic layer deposition

Yuniarto Widjaja and Charles B. Musgrave

Appl. Phys. Lett. 80, 3304 (2002); http://dx.doi.org/10.1063/1.1473237 (3 pages) | Cited 50 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The atomic layer deposition of alumina using water and trimethylaluminum is investigated using the density functional theory. The atomistic mechanisms of the two deposition half-cycles on Al–CH3∗ and Al–OH∗ surface sites are investigated. Both half-cycle reactions proceed through the formation of an Al–O Lewis acid-base complex followed by CH4 formation. The Al–O complexes are relatively stable, with formation energies between 0.57 and 0.74 eV. The CH4 formation activation energies range from 0.52 to 0.91 eV and both half-cycle reactions are exothermic with overall enthalpies of reaction between 1.30 and 1.70 eV. © 2002 American Institute of Physics.
Show PACS
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
82.33.Ya Chemistry of MOCVD and other vapor deposition methods
82.60.Cx Enthalpies of combustion, reaction, and formation
81.15.Aa Theory and models of film growth
68.55.A- Nucleation and growth
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces
71.15.Mb Density functional theory, local density approximation, gradient and other corrections

Manipulation of the equilibrium between diamond growth and renucleation to form a nanodiamond/amorphous carbon composite

X. T. Zhou, Q. Li, F. Y. Meng, I. Bello, C. S. Lee, S. T. Lee, and Y. Lifshitz

Appl. Phys. Lett. 80, 3307 (2002); http://dx.doi.org/10.1063/1.1476721 (3 pages) | Cited 25 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Composite films of ∼10 nm nanodiamond particles embedded in an amorphous carbon matrix were formed using a double bias assisted hot filament chemical vapor deposition system with a feeding gas mixture of 1% CH4:99% H2. The structure was obtained via the equilibrium of a multistage process including: (1) bias enhanced nucleation of diamond in an amorphous carbon matrix, (2) growth of both amorphous carbon and diamond, (3) suppression of the diamond growth by the surrounding amorphous carbon matrix, and (4) bias enhanced renucleation of diamond on the new amorphous carbon boundaries. The work adds insight to the diamond nucleation and growth processes. © 2002 American Institute of Physics.
Show PACS
81.05.U- Carbon/carbon-based materials
81.07.Bc Nanocrystalline materials
61.46.-w Structure of nanoscale materials
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.20.-n Methods of materials synthesis and materials processing

Recovery of microindents in a nickel–titanium shape-memory alloy: A “self-healing” effect

Wangyang Ni, Yang-Tse Cheng, and David S. Grummon

Appl. Phys. Lett. 80, 3310 (2002); http://dx.doi.org/10.1063/1.1476064 (3 pages) | Cited 48 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The thermally induced recovery of microscopic deformation in a nickel–titanium shape-memory alloy was examined. Surface deformation was simulated by indenting the alloy in the martensite phase at room temperature using both spherical and pyramidal indenters. We show that deformation in spherical microindents can be almost completely reversed by moderate heating. Partial recovery was observed for pyramidal impressions formed by a Vickers indenter and the recovery ratio was independent of the indentation depth. The observations were rationalized using the concept of representative strain and maximum stress under the spherical and pyramidal indenters. © 2002 American Institute of Physics.
Show PACS
81.40.Lm Deformation, plasticity, and creep
81.30.Kf Martensitic transformations
81.40.Np Fatigue, corrosion fatigue, embrittlement, cracking, fracture, and failure
81.05.Bx Metals, semimetals, and alloys
62.20.F- Deformation and plasticity
64.70.K- Solid-solid transitions
62.20.Qp Friction, tribology, and hardness
81.40.Ef Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization

Thin film alloy mixtures for high speed phase change optical storage: A study on (Ge1Sb2Te4)1−x(Sn1Bi2Te4)x

Tae-Yon Lee, Ki-Bum Kim, Byung-ki Cheong, Taek Sung Lee, Sung Jin Park, Kyeong Seok Lee, Won Mok Kim, and Soon Gwang Kim

Appl. Phys. Lett. 80, 3313 (2002); http://dx.doi.org/10.1063/1.1476705 (3 pages) | Cited 20 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
An approach is proposed to develop recording materials for high speed phase change optical data storage. It utilizes a thin film alloy mixture between a stoichiometric GeSbTe alloy and an additive ternary telluride alloy. Selection rules for an additive alloy are suggested. For a test, (Ge1Sb2Te4)1−x(Sn1Bi2Te4)x thin films are deposited by co-sputtering and their structural and thermal properties are studied. Ge1Sb2Te4 and Sn1Bi2Te4 are found to form a completely soluble pseudo-binary system, whose crystalline lattice parameters obey Vegard’s rule over the entire range of x (0<x<1). Furthermore, the alloy mixtures display an increasing tendency for crystallization with Sn1Bi2Te4 content. Dynamic tests of disk samples are made to show the effectiveness of the approach for high speed erasure. © 2002 American Institute of Physics.
Show PACS
42.79.Vb Optical storage systems, optical disks
78.66.Li Other semiconductors
81.15.Cd Deposition by sputtering
68.55.-a Thin film structure and morphology
61.66.Bi Elemental solids
61.66.Dk Alloys
64.70.K- Solid-solid transitions
61.50.Lt Crystal binding; cohesive energy
61.66.Fn Inorganic compounds

Time-resolved photoluminescence studies of free excitons in CuInS2 crystals

Kazuki Wakita, Kazuhito Nishi, Yoshihiko Ohta, and Naoji Nakayama

Appl. Phys. Lett. 80, 3316 (2002); http://dx.doi.org/10.1063/1.1476960 (3 pages) | Cited 6 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The time-resolved photoluminescence of free excitons in bulk single-crystal CuInS2 grown by the traveling heater method is examined. The decay of free exciton emission exhibits a double exponential curve at low temperature. The decay-time constant of the fast component increases monotonically with excitation density, whereas that of the slow component appears to be independent of excitation density. From this result, the fast and slow components are attributed to nonradiative and radiative recombination processes, respectively. The radiative lifetime of free excitons is estimated to be 320±30 ps at 10 K. © 2002 American Institute of Physics.
Show PACS
78.55.Hx Other solid inorganic materials
78.47.-p Spectroscopy of solid state dynamics
71.35.-y Excitons and related phenomena

Identification of nanocrystal nucleation and growth in Al85Ni5Y8Co2 metallic glass with quenched-in nuclei

J. Q. Wang, H. W. Zhang, X. J. Gu, K. Lu, F. Sommer, and E. J. Mittemeijer

Appl. Phys. Lett. 80, 3319 (2002); http://dx.doi.org/10.1063/1.1476388 (3 pages) | Cited 7 times

Online Publication Date: 29 April 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The crystallization kinetics of an Al85Ni5Y8Co2 metallic glass, with quenched-in nuclei and a well-defined glass transition temperature (Tg) upon heating, was monitored by x-ray diffraction, differential scanning calorimetry, in situ electrical resistance measurement, and high-resolution transmission electron microscopy. It was found that the formation and the evolution of the primary Al nanocrystals proceed at largely separated stages. The growth of a few quenched-in nuclei of Al occurs predominantly well below Tg. In the vicinity of Tg (T<Tg), an additional large number of nanoscale Al particles appear, prior to the primary crystallization temperature above Tg. Subsequently, the growth of the Al nanocrystals, both the quenched-in ones and those formed upon heating, dominates the primary crystallization reaction. © 2002 American Institute of Physics.
Show PACS
61.43.Fs Glasses
61.46.-w Structure of nanoscale materials
64.70.P- Glass transitions of specific systems
64.70.Q- Theory and modeling of the glass transition
72.15.Cz Electrical and thermal conduction in amorphous and liquid metals and alloys
Page 1 of 3 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close