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

20 Jan 2003

Volume 82, Issue 3, pp. 313-483

Issue Cover Spotlight Figure

Appl. Phys. Lett. 82, 370 (2003); http://dx.doi.org/10.1063/1.1537514 (3 pages)

Jan Schroers, Chris Veazey, and William L. Johnson
Enlarge Image | Read More
Page 1 of 3 Pages Next Page | Jump to Page
back to top
RSS Feeds

Operating characteristics of a semiconducting polymer laser pumped by a microchip laser

G. A. Turnbull, P. Andrew, W. L. Barnes, and I. D. W. Samuel

Appl. Phys. Lett. 82, 313 (2003); http://dx.doi.org/10.1063/1.1536249 (3 pages) | Cited 55 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the demonstration of a compact, all-solid-state polymer laser system featuring a microchip laser as the pump source. The laser was configured as a surface-emitting, two-dimensional distributed feedback laser, based on the conjugated polymer poly(2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylene vinylene). Pulsed, band-edge lasing was observed at 636 nm above a threshold pump energy of 4 nJ. The laser exhibited an energy slope efficiency of 6.8%, with a maximum output energy of 1.12 nJ at a pump energy of 20.4 nJ. The output beam had an azimuthally polarized annular profile with a beam quality factor (M2) of 2.2, close to the theoretical value of the lowest-order Laguerre–Gaussian and Bessel–Gaussian annular modes. We explain the origin of the azimuthal polarization as due to a coherent combination of the resonant fields supported by the two gratings. © 2003 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation
42.55.Sa Microcavity and microdisk lasers

Tunable liquid microlens

T. Krupenkin, S. Yang, and P. Mach

Appl. Phys. Lett. 82, 316 (2003); http://dx.doi.org/10.1063/1.1536033 (3 pages) | Cited 97 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A tunable liquid microlens capable of adjusting its focal length and lateral position is demonstrated. The microlens consists of a droplet of a transparent conductive liquid placed on a dielectric substrate with a low surface energy coating. By varying the voltage applied to a set of electrodes positioned underneath of the dielectric substrate, both the position and curvature of the microlens can be reversibly changed. The dependence of the microlens behavior on the properties of the materials involved is experimentally investigated and supported by theoretical calculations. Potential limitations of the microlens performance associated with the contact angle hysteresis and stick–slip phenomena are outlined and possible ways to alleviate them are proposed. Possible extensions of the proposed approach are also discussed. © 2003 American Institute of Physics.
Show PACS
42.79.Bh Lenses, prisms and mirrors

Lasing from InGaAs quantum dots in an injection microdisk

Lidong Zhang and E. Hu

Appl. Phys. Lett. 82, 319 (2003); http://dx.doi.org/10.1063/1.1538312 (3 pages) | Cited 17 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
An injection microdisk laser structure is realized using self-assembled InGaAs quantum dots (QDs) as the active layer. Single-mode continuous-wave lasing at ∼ 5 K from double layer ( ∼ 2.5×1010 cm−2 per layer) QDs in ∼ 4 μm diameter microdisks is reported. The threshold current of this device was as low as 69 μA. The estimated spontaneous emission factor is >0.05. © 2003 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.55.Sa Microcavity and microdisk lasers

Mode locking of semiconductor laser with curved waveguide and passive mode expander

C. A. Williamson, M. J. Adams, A. D. Ellis, and A. Borghesani

Appl. Phys. Lett. 82, 322 (2003); http://dx.doi.org/10.1063/1.1539277 (3 pages) | Cited 1 time

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Active mode locking is reported for a 1.55 μm semiconductor laser with a curved waveguide and passive mode expander, placed in a wavelength tunable external cavity. One facet with a very low reflectivity of 8×10−6 is achieved through a curved active region that tapers into an underlying passive waveguide, thus expanding the mode to give reduced divergence. 10 GHz pulses of 3.1 ps duration have been generated, with a linewidth of 0.81 nm. © 2003 American Institute of Physics.
Show PACS
42.60.Fc Modulation, tuning, and mode locking
42.55.Px Semiconductor lasers; laser diodes
42.60.By Design of specific laser systems

Enhanced stimulated Raman scattering in optical parametric oscillators from periodically poled KTiOPO4

V. Pasiskevicius, A. Fragemann, F. Laurell, R. Butkus, V. Smilgevicius, and A. Piskarskas

Appl. Phys. Lett. 82, 325 (2003); http://dx.doi.org/10.1063/1.1539923 (3 pages) | Cited 14 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Enhanced Raman scattering and concurrent Raman oscillation have been observed in nanosecond optical parametric oscillators in the near-infrared spectral region for certain periodicities of periodically poled KTiOPO4. The increased Raman activity is associated with direct excitation of the phonon overtone band by the idler wave. The decrease in efficiency of stimulated Raman scattering at crystal temperature above 80 °C is explained by higher dephasing rate of coherently driven lattice polarization due to interaction with thermally generated phonons. © 2003 American Institute of Physics.
Show PACS
42.65.Yj Optical parametric oscillators and amplifiers
42.65.Dr Stimulated Raman scattering; CARS
42.65.Es Stimulated Brillouin and Rayleigh scattering
78.30.Hv Other nonmetallic inorganics
77.22.Ej Polarization and depolarization
63.20.D- Phonon states and bands, normal modes, and phonon dispersion

Polarization dependent focusing lens by use of quantized Pancharatnam–Berry phase diffractive optics

Erez Hasman, Vladimir Kleiner, Gabriel Biener, and Avi Niv

Appl. Phys. Lett. 82, 328 (2003); http://dx.doi.org/10.1063/1.1539300 (3 pages) | Cited 16 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Quantized Pancharatnam–Berry phase diffractive optics using computer-generated space-variant subwavelength dielectric grating is presented. The formation of the geometrical phase is done by discrete orientation of the local subwavelength grating. We discuss a theoretical analysis and experimentally demonstrate a quantized geometrical blazed phase of polarization diffraction grating, as well as polarization dependent focusing lens for infrared radiation at wavelength 10.6 μm. © 2003 American Institute of Physics.
Show PACS
42.40.Eq Holographic optical elements; holographic gratings
42.79.Bh Lenses, prisms and mirrors
42.50.-p Quantum optics
42.40.Jv Computer-generated holograms
42.79.Dj Gratings

Realization of high-efficiency/high-luminance small-molecule organic light-emitting diodes: synergistic effects of siloxane anode functionalization/hole-injection layers, and hole/exciton-blocking/electron-transport layers

Qinglan Huang, Ji Cui, Jonathan G. C. Veinot, He Yan, and Tobin J. Marks

Appl. Phys. Lett. 82, 331 (2003); http://dx.doi.org/10.1063/1.1536268 (3 pages) | Cited 29 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
High-efficiency/high-luminance small-molecule organic light-emitting diodes (OLEDs) are fabricated by combining thin, covalently-bound triarylamine hole injection/adhesion interlayers with hole- and exciton-blocking/electron transport interlayers in tris(8-hydroxyquinolato)aluminum (III) (Alq)-based OLEDs. Power and forward external quantum efficiencies as high as 15.2 lm/W and 4.4±0.5%, respectively, and turn-on voltages ∼4.5 V are achieved in devices of the structure ITO/TPDSi2/NPB/Alq:DIQA/BCP/Li/MgAg [NPB=(N,N′-di(1-napthl)-N,N′-diphenyl benzidine)] TPDSi2 interlayers are straightforwardly fabricated by spin-casting N,N′-diphenyl-N,N′- bis(p-trichlorosilylpropylphenyl)(1,1′-biphenyl)-4,4′-diamine TPDSi2 onto the ITO surface, while 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) interlayers are introduced by thermal evaporation. High quantum efficiencies are attributed to the synergistic enhanced hole/electron injection and exciton confinement effects of the TPDSi2 and BCP interlayers, respectively. © 2003 American Institute of Physics.
Show PACS
85.60.Jb Light-emitting devices
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)
71.35.Lk Collective effects (Bose effects, phase space filling, and excitonic phase transitions)
73.61.Ph Polymers; organic compounds
73.50.Dn Low-field transport and mobility; piezoresistance
78.66.Qn Polymers; organic compounds

Organic single-layer white light-emitting diodes by exciplex emission from spin-coated blends of blue-emitting molecules

M. Mazzeo, D. Pisignano, F. Della Sala, J. Thompson, R. I. R. Blyth, G. Gigli, R. Cingolani, G. Sotgiu, and G. Barbarella

Appl. Phys. Lett. 82, 334 (2003); http://dx.doi.org/10.1063/1.1531217 (3 pages) | Cited 56 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on white electroluminescence (EL) emission from a single-layer light-emitting diode based on a binary blend of organic soluble blue-emitting molecules, i.e., a diamine derivative and a substituted thiophene-1,1-dioxide. Weakly voltage-dependent white color, of coordinates (0.39, 0.40) according to the standard of the Commission Internationale de l’Eclairage, is obtained from the superposition of the blue emission from the donor and a low-energy peak due to a charge-transfer complex between the two molecules (exciplex). The EL spectrum is broader and more structured than the photoluminescence one: this could be due to the activation of exciplexes with different conformations as inferred from quantum-chemistry calculations. © 2003 American Institute of Physics.
Show PACS
85.60.Jb Light-emitting devices
back to top
RSS Feeds

Radio-frequency microdischarge arrays for large-area cold atmospheric plasma generation

Yoou-Bin Guo and Franklin Chau-Nan Hong

Appl. Phys. Lett. 82, 337 (2003); http://dx.doi.org/10.1063/1.1539296 (3 pages) | Cited 29 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
By flowing gases through arrays of microhollow cathode holes, large area (12 mm in diameter) uniform and stable discharges could be generated by a rf power supply. Both the rf power and the gas flow through the cathode holes played key roles in maintaining uniform and stable discharges. The discharges could be stable for a period longer than one hour in pure helium (He) and in He containing 1% hexamethyldisiloxane (HMDSO). By using a third steel electrode biased with a pulse power supply (100 kHz, 50% duty cycle), the plasma from arrays of cathode holes could be extended to 20 mm in length. Amorphous carbon films deposited by the extended atmospheric plasma using 1% HMDSO/He reactants exhibited the same structure as those by low pressure plasma chemical vapor deposition. © 2003 American Institute of Physics.
Show PACS
52.77.Dq Plasma-based ion implantation and deposition
52.80.Pi High-frequency and RF discharges
81.15.Jj Ion and electron beam-assisted deposition; ion plating

Anomalous hard x-ray emission mode in a plasma focus discharge with hydrogen-argon mixtures

Hoon Heo and Duck Kyu Park

Appl. Phys. Lett. 82, 340 (2003); http://dx.doi.org/10.1063/1.1537872 (3 pages) | Cited 5 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We observed an anomalous discharge mode causing explosive surface evaporation and emission of hard x rays of 10–40 keV in the regime of the lower hydrogen partial pressures of hydrogen–argon mixture in a Mather type plasma focus device of 1.5 kJ. At the anomalous mode, the x rays were emitted from only the surface of the anode without emissions from a plasma column or hot spots, accompanying with explosive evaporations of the anode surface. © 2003 American Institute of Physics.
Show PACS
52.25.Os Emission, absorption, and scattering of electromagnetic radiation
52.59.Px Hard X-ray sources
52.80.Yr Discharges for spectral sources (including inductively coupled plasma)
52.80.Qj Explosions; exploding wires
07.85.Fv X- and γ-ray sources, mirrors, gratings, and detectors
52.58.Lq Z-pinches, plasma focus, and other pinch devices
52.59.Hq Dense plasma focus
52.75.-d Plasma devices
back to top
RSS Feeds

Oblique ion texturing of yttria-stabilized zirconia: the {211}〈111〉 structure

Paul Berdahl, Ronald P. Reade, Jinping Liu, Richard E. Russo, Les Fritzemeier, David Buczek, and Urs Schoop

Appl. Phys. Lett. 82, 343 (2003); http://dx.doi.org/10.1063/1.1536266 (3 pages) | Cited 2 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Amorphous (Zr,Y)Ox films were synthesized by reactive magnetron sputtering and subsequently crystallized by oblique ion bombardment. Crystalline texture nucleated by the ion beam was replicated by solid-phase epitaxial growth throughout the formerly amorphous yttria-stabilized zirconia (YSZ) film. The resulting YSZ films have (211) orientation normal to the substrate with in-plane directions (111), parallel, and (110), transverse, to the azimuth of the ion beam. We hypothesize that the texture mechanism involves ion-induced film compression and shear. The results, taken together with prior work, show that oblique ion texturing of amorphous films is a general phenomenon that can be used to fabricate substrates with more than one type of crystallographic orientation. © 2003 American Institute of Physics.
Show PACS
68.55.-a Thin film structure and morphology
61.80.Jh Ion radiation effects
61.82.Ms Insulators

Ultrarapid nanostructuring of poly(methylmethacrylate) films using Ga+ focused ion beams

Y. Liu, D. M. Longo, and R. Hull

Appl. Phys. Lett. 82, 346 (2003); http://dx.doi.org/10.1063/1.1536252 (3 pages) | Cited 4 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Topographical patterns were fabricated with speeds >103 features per second into poly(methylmethacrylate) (PMMA) films with a Ga+ focused ion beam. This material removal rate is orders of magnitude greater than expected in conventional sputtering. The relevant ion-beam sputtering parameters have been investigated to explore the mechanism of the extraordinary materials removal rate. It is speculated that structural changes during ion bombardment, specifically a beam-enhanced unzipping reaction of the PMMA chains, play an important role for the high material removal rate. These high throughput PMMA topographic patterns can be used as masters for high-resolution elastomer molding and microcontact printing. © 2003 American Institute of Physics.
Show PACS
81.65.Cf Surface cleaning, etching, patterning
81.05.Lg Polymers and plastics; rubber; synthetic and natural fibers; organometallic and organic materials
81.16.Rf Micro- and nanoscale pattern formation
81.16.Nd Micro- and nanolithography
61.41.+e Polymers, elastomers, and plastics
68.55.-a Thin film structure and morphology
85.40.Hp Lithography, masks and pattern transfer
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces
68.35.B- Structure of clean surfaces (and surface reconstruction)
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces

Light emission and microstructure of Mg-doped AlGaN grown on patterned sapphire

A. Bell, R. Liu, F. A. Ponce, H. Amano, I. Akasaki, and D. Cherns

Appl. Phys. Lett. 82, 349 (2003); http://dx.doi.org/10.1063/1.1537517 (3 pages) | Cited 35 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Distinct crystalline and optical properties have been observed in Mg-doped Al0.03Ga0.97N grown on a patterned sapphire substrate; the pattern consisting of etched trenches along the sapphire 〈11math0〉 direction. The epilayer has two distinct regions: one grown directly onto the sapphire mesa and the other an epitaxial lateral overgrowth (ELO) region that overhangs the trench. Transmission electron microscopy shows the presence of pyramidal defects as well as large dislocation densities in the region grown directly on sapphire. In contrast, the ELO region is defect free and contains no Mg-related pyramidal defects. Cathodoluminescence measurements show superior near-band-edge emission in the ELO region, suggesting that the emission is susceptible to nonradiative centers caused by the high defect density in the rest of the sample. The Mg-related donor–acceptor-pair emission is fairly uniform throughout the film, indicating that it is not affected by the nonradiative centers. These optical and structural properties of AlGaN are closely related to the direction of the growth front. © 2003 American Institute of Physics.
Show PACS
78.66.Fd III-V semiconductors
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
78.60.Hk Cathodoluminescence, ionoluminescence
61.72.uj III-V and II-VI semiconductors
81.05.Ea III-V semiconductors
68.55.-a Thin film structure and morphology
73.20.Hb Impurity and defect levels; energy states of adsorbed species

Mechanical gating of coupled nanoelectromechanical resonators operating at radio frequency

Laura Pescini, Heribert Lorenz, and Robert H. Blick

Appl. Phys. Lett. 82, 352 (2003); http://dx.doi.org/10.1063/1.1536032 (3 pages) | Cited 7 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report measurements on hybrid gold/silicon suspended nanostructures operating as electromechanical resonators in the rf regime. The device consists of two nanoresonators operating as mechanical gating elements. We demonstrate this gating mechanism by tuning the mechanical modes of the device. Detailed numerical calculations are performed to model the device. © 2003 American Institute of Physics.
Show PACS
85.85.+j Micro- and nano-electromechanical systems (MEMS/NEMS) and devices
07.10.Cm Micromechanical devices and systems

Semiconductor absorption in photonic crystals

R. Eichmann, B. Pasenow, T. Meier, T. Stroucken, P. Thomas, and S. W. Koch

Appl. Phys. Lett. 82, 355 (2003); http://dx.doi.org/10.1063/1.1537455 (3 pages) | Cited 5 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Absorption spectra of semiconductor structures in photonic crystal environments are investigated numerically. It is shown that the periodic dielectric structuring changes the local optical and Coulomb interaction properties of semiconductor electron–hole excitations. The structurally induced modifications offer the possibility to design important aspects of the optoelectronic semiconductor properties. © 2003 American Institute of Physics.
Show PACS
42.70.Qs Photonic bandgap materials
78.40.-q Absorption and reflection spectra: visible and ultraviolet
72.30.+q High-frequency effects; plasma effects

Transpolyacetylene chains in hydrogenated amorphous carbon films free of nanocrystalline diamond

F. Piazza, A. Golanski, S. Schulze, and G. Relihan

Appl. Phys. Lett. 82, 358 (2003); http://dx.doi.org/10.1063/1.1538349 (3 pages) | Cited 17 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The microstructure of distributed electron cyclotron resonance plasma-deposited hydrogenated amorphous carbon films (a-C:H) was investigated using electron diffraction, Raman spectroscopy, and Fourier transform infrared spectroscopy. Experimental evidence of the existence of transpolyacetylene (TPA) chains in a-C:H films free of nanocrystalline diamond is presented. The values of the mean bond angles and lengths and first neighbor numbers are consistent with the TPA data. The Raman spectra were fitted using the G and D bands and the bands centered at 1140, 1233, and 1475 cm−1 assigned to TPA chains modes. The relative intensity of the latter decreases while hydrogen content decreases. A significant sp2-CH olefinic mode contribution to the infrared stretching band is observed for the low-density films (∼1.2 g/cm3). TPA chains growth is enhanced when ion current density and energy decrease. © 2003 American Institute of Physics.
Show PACS
68.55.-a Thin film structure and morphology
81.05.U- Carbon/carbon-based materials
52.77.Dq Plasma-based ion implantation and deposition
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
78.35.+c Brillouin and Rayleigh scattering; other light scattering
78.66.Jg Amorphous semiconductors; glasses
61.41.+e Polymers, elastomers, and plastics

Chemical structure of the interface between MgO films and Fe(001)

H. Oh, S. B. Lee, Jikeun Seo, H. G. Min, and J.-S. Kim

Appl. Phys. Lett. 82, 361 (2003); http://dx.doi.org/10.1063/1.1538311 (3 pages) | Cited 17 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The chemical structure of the interface formed during MgO growth on Fe(001) is studied by vibration spectroscopy employing a high resolution electron energy loss spectrometer. We find direct, spectroscopic evidence for the formation of FeO layer at the interface that is triggered by the dissociation of oxygen molecule by deposited Mg. Even though the growth conditions of MgO are widely varied, FeO cannot be eradicated at the interface. Hence, we propose that the phase where FeO and MgO coexist at the interface, is an entropically stabilized one in regards to the very small difference between the bond dissociation energy of FeO and that of MgO. © 2003 American Institute of Physics.
Show PACS
68.35.Ct Interface structure and roughness
79.20.Uv Electron energy loss spectroscopy
68.35.Fx Diffusion; interface formation

Formation of dispersions using “flow focusing” in microchannels

Shelley L. Anna, Nathalie Bontoux, and Howard A. Stone

Appl. Phys. Lett. 82, 364 (2003); http://dx.doi.org/10.1063/1.1537519 (3 pages) | Cited 627 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A flow-focusing geometry is integrated into a microfluidic device and used to study drop formation in liquid–liquid systems. A phase diagram illustrating the drop size as a function of flow rates and flow rate ratios of the two liquids includes one regime where drop size is comparable to orifice width and a second regime where drop size is dictated by the diameter of a thin “focused” thread, so drops much smaller than the orifice are formed. Both monodisperse and polydisperse emulsions can be produced. © 2003 American Institute of Physics.
Show PACS
47.60.-i Flow phenomena in quasi-one-dimensional systems
47.85.Np Fluidics
47.55.Kf Particle-laden flows
82.70.Kj Emulsions and suspensions
82.70.-y Disperse systems; complex fluids
47.55.D- Drops and bubbles

Stress analysis of AlxGa1−xN films with microcracks

D. Rudloff, T. Riemann, J. Christen, Q. K. K. Liu, A. Kaschner, A. Hoffmann, Ch. Thomsen, K. Vogeler, M. Diesselberg, S. Einfeldt, and D. Hommel

Appl. Phys. Lett. 82, 367 (2003); http://dx.doi.org/10.1063/1.1534408 (3 pages) | Cited 16 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Thick AlxGa1−xN epilayer with microcracks grown by metalorganic vapor-phase epitaxy on a GaN buffer above a (0001) sapphire substrate was comprehensively characterized by spatially and spectrally resolved cathodoluminescence (CL) and micro-Raman (μ-Raman) spectroscopy. The variation of the CL line shift and the μ-Raman measurements between the microcracks are consistent with the interpretation that AlGaN is to a large extent stressed like a two dimensional film between the microcracks with nearly full relaxation close to the cracks. A satisfactory theoretical confirmation of this stress distribution was obtained by a three-dimensional finite-element application of the elasticity theory. © 2003 American Institute of Physics.
Show PACS
68.60.Bs Mechanical and acoustical properties
62.20.M- Structural failure of materials
81.40.Np Fatigue, corrosion fatigue, embrittlement, cracking, fracture, and failure
78.60.Hk Cathodoluminescence, ionoluminescence
78.30.Fs III-V and II-VI semiconductors
78.66.Fd III-V semiconductors
81.05.Ea III-V semiconductors
62.40.+i Anelasticity, internal friction, stress relaxation, and mechanical resonances

Amorphous metallic foam

Jan Schroers, Chris Veazey, and William L. Johnson

Appl. Phys. Lett. 82, 370 (2003); http://dx.doi.org/10.1063/1.1537514 (3 pages) | Cited 50 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The bulk glass forming alloy Pd43Ni10Cu27P20 is processed into a low-density amorphous metallic foam. Pd43Ni10Cu27P20 is mixed with hydrated B2O3, which releases gas at elevated temperature and/or low pressure. Very homogeneous foams are achieved due to the high viscosity of the alloy even at its liquidus temperature. By processing at the liquidus temperature and decreasing the pressure to 10−2 mbar, well-distributed bubbles expand to foam the material. Foam densities as low as 1.4×103 kg/m3 were obtained, corresponding to a bubble volume fraction of 84%. The bubble diameter ranges between 2×10−4 and 1×10−3 m. Thermal analysis by differential scanning calorimetry confirms the amorphous nature of the foam. Furthermore, it reveals that the foam’s thermal stability is comparable to the bulk material. © 2003 American Institute of Physics.
Show PACS
81.05.Rm Porous materials; granular materials
82.70.Rr Aerosols and foams
81.05.Bx Metals, semimetals, and alloys
61.72.Qq Microscopic defects (voids, inclusions, etc.)
61.43.Dq Amorphous semiconductors, metals, and alloys
61.43.Gt Powders, porous materials
81.20.-n Methods of materials synthesis and materials processing

Transmission modulation in the passband of polystyrene photonic crystals

Honglian Guo, Hongyi Chen, Peigen Ni, Qi Zhang, Bingying Cheng, and Daozhong Zhang

Appl. Phys. Lett. 82, 373 (2003); http://dx.doi.org/10.1063/1.1539280 (3 pages) | Cited 13 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The periodic disturbance in transmittance of polystyrene photonic crystal is detected in our experiment. The peak-to-peak intervals of the periodic disturbance vary with the wavelength. It is attributed to the propagation of the whispering gallery mode in polystyrene spheres. The results show that the periodically arrayed particles may affect light transfer outside the gap band, which implies the possibility in applications of photonic crystal films. © 2003 American Institute of Physics.
Show PACS
42.70.Qs Photonic bandgap materials
42.70.Jk Polymers and organics
78.66.Qn Polymers; organic compounds
78.40.Me Organic compounds and polymers

Optical transitions in GaInNAs/GaAs multi-quantum wells with varying N content investigated by photoluminescence excitation spectroscopy

H. D. Sun, M. D. Dawson, M. Othman, J. C. L. Yong, J. M. Rorison, P. Gilet, L. Grenouillet, and A. Million

Appl. Phys. Lett. 82, 376 (2003); http://dx.doi.org/10.1063/1.1539921 (3 pages) | Cited 24 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on the nitrogen-concentration dependence of optical transitions between quantized states of electrons and holes in GaInNAs/GaAs multi-quantum wells. Using low-temperature photoluminescence excitation spectroscopy, systematic studies have been performed on a series of samples with nitrogen concentrations in the range 0%–1.14%. The observed data were compared with theoretical fitting based on the band anticrossing model in which the localized N states interact with the extended states in the conduction band, taking strain effects into account. Our results are consistent with the band anticrossing model, but with differing coupling strength between different quantum states of electrons in the quantum wells. © 2003 American Institute of Physics.
Show PACS
78.67.De Quantum wells
81.07.St Quantum wells
73.21.Fg Quantum wells
78.55.Cr III-V semiconductors
81.05.Ea III-V semiconductors

One-dimensional continuum and exciton states in quantum wires

Hidefumi Akiyama, Masahiro Yoshita, Loren N. Pfeiffer, Ken W. West, and Aron Pinczuk

Appl. Phys. Lett. 82, 379 (2003); http://dx.doi.org/10.1063/1.1539552 (3 pages) | Cited 24 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
High-quality T-shaped quantum wires are fabricated by cleaved-edge overgrowth with molecular-beam epitaxy on the interface improved by a growth-interrupt high-temperature anneal. Characterization by micro-photoluminescence (PL) and PL excitation (PLE) spectroscopy at 5 K reveals high uniformity, a sharp spectral width, and a small Stokes shift of one-dimensional (1D) excitons. The PLE spectrum for 1D states shows a large peak of ground-state excitons and a small absorption band ascribed to 1D continuum states with an onset at 11 meV above the exciton peak. © 2003 American Institute of Physics.
Show PACS
73.21.Hb Quantum wires
78.67.Lt Quantum wires
71.35.Cc Intrinsic properties of excitons; optical absorption spectra
78.55.-m Photoluminescence, properties and materials
81.07.Vb Quantum wires
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
81.40.Gh Other heat and thermomechanical treatments

Local structure of crystallized GeTe films

A. V. Kolobov, J. Tominaga, P. Fons, and T. Uruga

Appl. Phys. Lett. 82, 382 (2003); http://dx.doi.org/10.1063/1.1539926 (3 pages) | Cited 23 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The structure of crystallized GeTe films has been studied by x-ray absorption fine structure spectroscopy. We find that in addition to Ge–Te bonds (2.20 and 3.13 Å) ∼10% of Ge–Ge bonds are present. Our results indicate that the crystallized GeTe film consists of GeTe crystallites with 10% Ge vacancies, separated by a quasiamorphous-Ge phase. © 2003 American Institute of Physics.
Show PACS
68.55.-a Thin film structure and morphology
61.43.Fs Glasses
78.70.Dm X-ray absorption spectra
61.72.J- Point defects and defect clusters
61.05.cj X-ray absorption spectroscopy: EXAFS, NEXAFS, XANES, etc.

Hydrogen incorporation and diffusivity in plasma-exposed bulk ZnO

K. Ip, M. E. Overberg, Y. W. Heo, D. P. Norton, S. J. Pearton, C. E. Stutz, B. Luo, F. Ren, D. C. Look, and J. M. Zavada

Appl. Phys. Lett. 82, 385 (2003); http://dx.doi.org/10.1063/1.1539927 (3 pages) | Cited 92 times

Online Publication Date: 15 January 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Hydrogen incorporation depths of >25 μm were obtained in bulk, single-crystal ZnO during exposure to 2H plasmas for 0.5 h at 300 °C, producing an estimated diffusivity of ∼ 8×10−10 cm2/V⋅s at this temperature. The activation energy for diffusion was 0.17±0.12 eV, indicating an interstitial mechanism. Subsequent annealing at 500–600 °C was sufficient to evolve all of the hydrogen out of the ZnO, at least to the sensitivity of secondary ion mass spectrometry (<5×1015 cm−3). The thermal stability of hydrogen retention is slightly greater when the hydrogen is incorporated by direct implantation relative to plasma exposure, due to trapping at residual damage in the former case. © 2003 American Institute of Physics.
Show PACS
66.30.J- Diffusion of impurities
61.72.S- Impurities in crystals
61.72.Cc Kinetics of defect formation and annealing
61.72.uj III-V and II-VI semiconductors
61.72.Yx Interaction between different crystal defects; gettering effect
Page 1 of 3 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close