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

11 Jun 2007

Volume 90, Issue 24, Articles (24xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 90, 243104 (2007); http://dx.doi.org/10.1063/1.2748211 (3 pages)

D. G. de Oteyza, T. N. Krauss, E. Barrena, S. Sellner, H. Dosch, and J. O. Ossó
Enlarge Image | Read More
Page 1 of 5 Pages Next Page | Jump to Page
back to top
RSS Feeds

Correlation between optoelectronic and structural properties and epilayer thickness of AlN

B. N. Pantha, R. Dahal, M. L. Nakarmi, N. Nepal, J. Li, J. Y. Lin, H. X. Jiang, Q. S. Paduano, and David Weyburne

Appl. Phys. Lett. 90, 241101 (2007); http://dx.doi.org/10.1063/1.2747662 (3 pages) | Cited 18 times

Online Publication Date: 11 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
AlN epilayers were grown by metal organic chemical vapor deposition on sapphire substrates. X-ray diffraction measurements revealed that the threading dislocation (TD) density, in particular, the edge TD density, decreases considerably with increasing the epilayer thickness. Photoluminescence results showed that the intensity ratio of the band edge emission to the defect related emission increases linearly with increasing the epilayer thickness. Moreover, the dark current of the fabricated AlN metal-semiconductor-metal deep ultraviolet (DUV) photodetectors decreases drastically with the AlN epilayer thickness. The results suggested that one effective way for attaining DUV optoelectronic devices with improved performance is to increase the thickness of the AlN epilayer template, which results in the reduction of the TD density.
Show PACS
78.66.Fd III-V semiconductors
78.55.Cr III-V semiconductors
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
68.55.-a Thin film structure and morphology
61.72.Ff Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.)
85.60.Gz Photodetectors (including infrared and CCD detectors)

Dynamic behavior of 1040 nm semiconductor disk lasers on a nanosecond time scale

W. Diehl, P. Brick, S. Chatterjee, S. Horst, K. Hantke, W. W. Rühle, W. Stolz, A. Thränhardt, and S. W. Koch

Appl. Phys. Lett. 90, 241102 (2007); http://dx.doi.org/10.1063/1.2748079 (3 pages) | Cited 8 times

Online Publication Date: 11 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The nanosecond dynamics of near-infrared semiconductor disk lasers is investigated experimentally and theoretically. Lasing and photoluminescence following barrier pumping are analyzed. Their spectral and temporal features such as luminescence overshoot and clamping, delay of lasing onset, and redshift of the emission are explained by a rate equation model taking into account the microscopic gain and luminescence.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.By Design of specific laser systems
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.65.Re Ultrafast processes; optical pulse generation and pulse compression

Amplified spontaneous emission in para-sexiphenyl bulk single crystals

Paolo A. Losio, Christoph Hunziker, and Peter Günter

Appl. Phys. Lett. 90, 241103 (2007); http://dx.doi.org/10.1063/1.2748086 (3 pages) | Cited 13 times

Online Publication Date: 11 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Amplified spontaneous emission (ASE) in single crystals of para-sexiphenyl grown in the β phase by vapor transport is demonstrated upon photoexcitation at 355 nm. Excitation with femtosecond laser pulses leads to dual wavelength ASE at 427 and 450 nm, while excitation with nanosecond laser pulses leads to ASE only at 450 nm. The threshold fluences for nanosecond and femtosecond pumpings are determined to be 885 and 110 μJ/cm2, respectively. Additionally, the singlet exciton annihilation rate is measured to be γss = (1.2±0.1)×10−6 cm3 s−1.
Show PACS
78.45.+h Stimulated emission
42.70.-a Optical materials
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
42.65.Re Ultrafast processes; optical pulse generation and pulse compression

Tuning hole injection and charge recombination with self-assembled monolayer on silver anode in top-emitting organic light-emitting diodes

Kun-Yang Wu, Yu-Tai Tao, and Hung-Wei Huang

Appl. Phys. Lett. 90, 241104 (2007); http://dx.doi.org/10.1063/1.2747667 (3 pages) | Cited 11 times

Online Publication Date: 11 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A series of n-alkanethiol, cyano-terminated n-alkanethiol, and fluorine-substituted benzyl mercaptans were used to modify the silver anode in the fabrication of top-emitting electroluminescent devices. The efficiency of charge injection and device performance were investigated. The study shows that the size/direction of the dipole associated with the monolayer-forming molecule serves to modulate the metal work function and the charge injection barrier, whereas the alkyl chain length allows a fine tuning of charge balance in the recombination zone. A high current efficiency of ∼ 10.2 cd/A and a luminescence of ∼ 10 800 cd/m2 at 200 mA were achieved with the NC–C11–SH-modified devices.
Show PACS
85.60.Jb Light-emitting devices

Transformation media that rotate electromagnetic fields

Huanyang Chen and C. T. Chan

Appl. Phys. Lett. 90, 241105 (2007); http://dx.doi.org/10.1063/1.2748302 (3 pages) | Cited 166 times

Online Publication Date: 11 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors suggest a way to manipulate electromagnetic waves by introducing a rotation mapping of coordinates that can be realized by a specific transformation of the permittivity and permeability of a shell surrounding an enclosed domain. Inside the enclosed domain, the information from the outside will appear as if it is coming from a different angle. Numerical simulations were performed to illustrate these properties.
Show PACS
42.25.Ja Polarization
78.20.Ek Optical activity
77.22.Ch Permittivity (dielectric function)

Dramatic change of guiding properties in heavily Yb-doped, soft-glass active fibers caused by optical pumping

Pavel Polynkin, Valery Temyanko, Jerome Moloney, and N. Peyghambarian

Appl. Phys. Lett. 90, 241106 (2007); http://dx.doi.org/10.1063/1.2748311 (3 pages) | Cited 2 times

Online Publication Date: 12 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors report experimentally observed qualitative changes of the waveguiding properties in ytterbium-doped fibers with high concentration of doping when the fibers are optically pumped with light at the 975 nm wavelength. They found that when concentration of Yb2O3 in a single-mode fiber exceeds ∼ 10 wt. % and the pump power is gradually increased, the fiber first looses index-induced guidance, and then regains guidance as the population inversion in Yb+3 ions becomes sufficient for gain guiding. The associated variation of the mode-field diameter is a practically important effect that will complicate design and operation of fiber lasers and amplifiers based on highly Yb-doped glass.
Show PACS
42.55.Wd Fiber lasers
42.60.By Design of specific laser systems

Femtosecond laser writing of waveguides in periodically poled lithium niobate preserving the nonlinear coefficient

Roberto Osellame, Mirko Lobino, Nicola Chiodo, Marco Marangoni, Giulio Cerullo, Roberta Ramponi, Henry T. Bookey, Robert R. Thomson, Nicholas D. Psaila, and Ajoy K. Kar

Appl. Phys. Lett. 90, 241107 (2007); http://dx.doi.org/10.1063/1.2748328 (3 pages) | Cited 11 times

Online Publication Date: 13 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Optical waveguides have been inscribed in periodically poled lithium niobate by femtosecond laser pulses with the multiscan technique. Second harmonic generation experiments from a fundamental wavelength of 1567 nm demonstrate that the nonlinear optical coefficient in the waveguides is preserved, yielding a conversion efficiency of 18% W−1.
Show PACS
42.82.Et Waveguides, couplers, and arrays
42.79.Gn Optical waveguides and couplers
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
42.82.Cr Fabrication techniques; lithography, pattern transfer
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation

Gain characteristics of InAs/InGaAsP quantum dot semiconductor optical amplifiers at 1.5 μm

N. J. Kim, J. M. Oh, M. D. Kim, D. Lee, S. H. Pyun, W. G. Jeong, and J. W. Jang

Appl. Phys. Lett. 90, 241108 (2007); http://dx.doi.org/10.1063/1.2748846 (3 pages) | Cited 7 times

Online Publication Date: 13 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors have fabricated ridge waveguide quantum dot (QD) semiconductor optical amplifiers (SOAs) on InP substrates that operate in the 1.5 μm region. The active layer consists of InAs/InGaAsP QD layers with a high dot density, but which still have good isolation between dots in the lateral and vertical directions, as confirmed by time-resolved photoluminescence measurements. One of these QD SOAs exhibited a fiber-to-fiber gain of 22.5 dB and a chip gain of 37 dB at 1.51 μm. The spectral gain shape was found to be maintained for variations of the peak gain from 12 to 22 dB, reflecting the zero-dimensional density of states at room temperature.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.By Design of specific laser systems

Freestanding waveguides in silicon

P. Y. Yang, G. Z. Mashanovich, I. Gomez-Morilla, W. R. Headley, G. T. Reed, E. J. Teo, D. J. Blackwood, M. B. H. Breese, and A. A. Bettiol

Appl. Phys. Lett. 90, 241109 (2007); http://dx.doi.org/10.1063/1.2749175 (3 pages) | Cited 13 times

Online Publication Date: 13 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Using a direct-write process for the production of three dimensional microstructures on a semiconductor, freestanding waveguides have been realized in silicon. The waveguides are produced by a focused beam of high energy protons that is scanned over a silicon substrate. The latent image of the scan is subsequently developed by electrochemical etching. Herein the authors report on the fabrication method as well as determining the propagation loss of these structures. Propagation loss values of 13.4 and 14.6 dB/cm were obtained for these preliminary structures for transverse electric and transverse magnetic polarizations, respectively.
Show PACS
42.82.Et Waveguides, couplers, and arrays
42.79.Gn Optical waveguides and couplers
42.82.Cr Fabrication techniques; lithography, pattern transfer

Ground state lasing at 1.34 μm from InAs/GaAs quantum dots grown by antimony-mediated metal organic chemical vapor deposition

D. Guimard, Y. Arakawa, M. Ishida, S. Tsukamoto, M. Nishioka, Y. Nakata, H. Sudo, T. Yamamoto, and M. Sugawara

Appl. Phys. Lett. 90, 241110 (2007); http://dx.doi.org/10.1063/1.2748082 (3 pages) | Cited 16 times

Online Publication Date: 13 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors report the fabrication of GaAs-based quantum dot (QD) lasers grown by metal organic chemical vapor deposition above 1.30 μm. They fabricated a laser diode with five stacked InAs/Sb:GaAs(100) QD layers, grown by antimony-surfactant-mediated growth. Ground state lasing was obtained at 1.34 μm, with internal quantum efficiency of 62%, internal loss of 4.5 cm−1 and ground state modal gain above 12 cm−1. Lasing above 1.30 μm could be achieved because of the beneficial effects of antimony on both the coherent InAs/Sb:GaAs QD density and the suppression of the emission blueshift, usually observed for InAs/GaAs QDs during postgrowth annealing at 600 °C.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.By Design of specific laser systems
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Temperature-dependent brightening and darkening of photoluminescence from PbS quantum dots in glasses

Chao Liu, Yong Kon Kwon, and Jong Heo

Appl. Phys. Lett. 90, 241111 (2007); http://dx.doi.org/10.1063/1.2748849 (3 pages) | Cited 9 times

Online Publication Date: 14 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors report that the darkening and brightening of photoluminescence from PbS quantum dots can be controlled by adjusting the temperature and excitation intensity. Intensity of the photoluminescence from PbS quantum dots increased with time (photobrightening) when temperature was below 150 K. On the other hand, darkening was observed at temperatures above 150 K. It was also possible to make a reversible change between photobrightening and photodarkening from the same specimen through the careful control of the temperature and excitation intensity.
Show PACS
78.67.Hc Quantum dots
78.55.Et II-VI semiconductors

Enhanced outcoupling from organic light-emitting diodes using aperiodic dielectric mirrors

Mukul Agrawal, Yiru Sun, Stephen R. Forrest, and Peter Peumans

Appl. Phys. Lett. 90, 241112 (2007); http://dx.doi.org/10.1063/1.2748859 (3 pages) | Cited 14 times

Online Publication Date: 14 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Aperiodic dielectric stacks between the substrate and transparent anode in organic light-emitting diodes are used to improve the optical outcoupling efficiency. The authors demonstrate that a nine-layer SiO2/SiNx aperiodic dielectric stack improves the brightness by 80% within a 60° viewing cone for a red-emitting organic light-emitting diode, while maintaining a Lambertian emission pattern. As the refractive index contrast between the two materials used in a two-component multilayer dielectric stack is increased, a brightness improvement of 170% in a 60° viewing cone is achievable while maintaining a Lambertian emission profile.
Show PACS
85.60.Jb Light-emitting devices
42.79.Bh Lenses, prisms and mirrors
42.79.Wc Optical coatings

Quasi-incoherent propagation in waveguide arrays

Alexander Szameit, Felix Dreisow, Holger Hartung, Stefan Nolte, Andreas Tünnermann, and Falk Lederer

Appl. Phys. Lett. 90, 241113 (2007); http://dx.doi.org/10.1063/1.2735953 (3 pages) | Cited 41 times

Online Publication Date: 15 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this letter a “quasi-incoherent” propagation in waveguide arrays is theoretically derived and experimentally verified. Depending on the initial light distribution the propagation in a waveguide array after multiwaveguide excitation exhibits an interference pattern or not. For the experimental verification the waveguide array is realized in OH rich fused silica by femtosecond laser direct writing. The light propagation within the array is directly visible due to the fluorescence of the created color centers. A precise excitation of different waveguides is achieved using a phase grating.
Show PACS
42.79.Gn Optical waveguides and couplers
42.79.Dj Gratings
42.62.-b Laser applications

Phase sensitive photodiode based on guided resonant absorption

Bong-Seok Choi, Yoshiaki Kanamori, and Kazuhiro Hane

Appl. Phys. Lett. 90, 241114 (2007); http://dx.doi.org/10.1063/1.2749180 (3 pages) | Cited 3 times

Online Publication Date: 15 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A phase sensitive photodiode is fabricated on a thin (380 nm) silicon layer with a subwavelength (670 nm period) grating. Optical absorption of the photodiode is enhanced by guided resonance of the grating to approximately 81% at the incident angle of 34.6° under TE polarization. Utilizing light beams impinging at the angles with enhanced sensitivities, a phase of two beams interfering in the silicon layer is precisely detected. The compact structure of the proposed detector can be used in several microinterferometers and integrated optics.
Show PACS
85.60.Dw Photodiodes; phototransistors; photoresistors

Mode switching and beam steering in photonic crystal heterostructures implemented with vertical-cavity surface-emitting lasers

L. D. A. Lundeberg and E. Kapon

Appl. Phys. Lett. 90, 241115 (2007); http://dx.doi.org/10.1063/1.2748330 (3 pages) | Cited 2 times

Online Publication Date: 15 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors demonstrate electrically controlled mode switching and beam steering in separate-contact photonic crystal heterostructures implemented with two-dimensional arrays of coupled vertical-cavity surface-emitting lasers. Two weakly coupled, lasing photonic crystal domains are switched in and out of mutual coherence by controlling the injected currents. Switching of the transverse lasing mode is accompanied by corresponding variations in the far-field pattern and the emission wavelength. Proper adjustment of the driving currents also allows steering of the beam of the ensemble of coupled lasers.
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
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation

Bragg surface wave device based on porous silicon and its application for sensing

E. Guillermain, V. Lysenko, R. Orobtchouk, T. Benyattou, S. Roux, A. Pillonnet, and P. Perriat

Appl. Phys. Lett. 90, 241116 (2007); http://dx.doi.org/10.1063/1.2747671 (3 pages) | Cited 24 times

Online Publication Date: 15 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Results concerning a Bragg surface wave device based on porous silicon and intended for sensing application are reported. Existence of optical surface waves on Bragg structures is experimentally shown. Such device is expected to be very sensitive to the grafting of biological molecules. The authors demonstrate this sensing effect by grafting of amine chemical groups. The optical characterization using m-line spectroscopy shows that the increase of the coupling angle is about 20° after the amine grafting. The authors show that porosity is essential for reaching this high sensitivity.
Show PACS
87.80.-y Biophysical techniques (research methods)
07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing
87.15.-v Biomolecules: structure and physical properties
87.64.-t Spectroscopic and microscopic techniques in biophysics and medical physics

Mode structure of the L3 photonic crystal cavity

A. R. A. Chalcraft, S. Lam, D. O’Brien, T. F. Krauss, M. Sahin, D. Szymanski, D. Sanvitto, R. Oulton, M. S. Skolnick, A. M. Fox, D. M. Whittaker, H.-Y. Liu, and M. Hopkinson

Appl. Phys. Lett. 90, 241117 (2007); http://dx.doi.org/10.1063/1.2748310 (3 pages) | Cited 44 times

Online Publication Date: 15 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors investigate the multiple confined modes of GaAs L3 photonic crystal air-bridge cavities, using single layers of InAs quantum dots as active internal light sources. Theoretical results for the energies, quality factors, and emission polarizations of the first five modes are compared to experimental data for cavities with lattice periods ranging from 240 to 270 nm. The authors also present in-plane field distributions for each mode. In addition to the well-known quality factor improvement of the fundamental mode, they show that outward displacement of the end-holes selectively redshifts modes with large end-hole-field overlaps, thus reordering the modes.
Show PACS
42.70.Qs Photonic bandgap materials
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
78.66.Fd III-V semiconductors
78.55.Cr III-V semiconductors

Vectorial electric field measurement using isotropic electro-optic crystals

G. Gaborit, J.-L. Coutaz, and L. Duvillaret

Appl. Phys. Lett. 90, 241118 (2007); http://dx.doi.org/10.1063/1.2748364 (3 pages) | Cited 3 times

Online Publication Date: 15 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors present a two-component electric field measurement using a single electro-optic crystal and a single laser probe beam. This vectorial electric field measurement based on polarization state modulation is possible using isotropic electro-optic crystals for which directions of the eigendielectric axes are directly linked to the direction of the applied electric field. The proposed method can be used either for continuous wave or single shot measurements as the two electric field components are measured simultaneously.
Show PACS
06.30.Ka Basic electromagnetic quantities
42.62.Eh Metrological applications; optical frequency synthesizers for precision spectroscopy
78.20.Jq Electro-optical effects

HgCdTe negative luminescence devices with high internal and external efficiencies in the midinfrared

J. R. Lindle, W. W. Bewley, I. Vurgaftman, J. R. Meyer, M. L. Thomas, E. C. Piquette, D. D. Edwall, and W. E. Tennant

Appl. Phys. Lett. 90, 241119 (2007); http://dx.doi.org/10.1063/1.2748363 (3 pages) | Cited 6 times

Online Publication Date: 15 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors report the fabrication and characterization of mid-IR HgCdTe negative luminescence (NL) devices grown on silicon substrates. Sensitive optical modulation measurements of the 5 mm square array with ∼ 5.4 μm cutoff and single-layer antireflection (AR) coating yield an internal NL efficiency of 98% at room temperature. This is the highest ever reported, and represents a factor-of-50 suppression of the blackbody emission. The corresponding external NL efficiency of 86% is consistent with the internal efficiency and the spectrally weighted reflectivity of 15%, which could be improved substantially through the incorporation of a state-of-the-art multilayer AR coating.
Show PACS
42.82.Gw Other integrated-optical elements and systems
42.72.Ai Infrared sources
07.57.Hm Infrared, submillimeter wave, microwave, and radiowave sources

Hybrid three-arm coupler with long range surface plasmon polariton and dielectric waveguides

Fang Liu, Yi Rao, Xuan Tang, Ruiyuan Wan, Yidong Huang, Wei Zhang, and Jiangde Peng

Appl. Phys. Lett. 90, 241120 (2007); http://dx.doi.org/10.1063/1.2747666 (3 pages) | Cited 8 times

Online Publication Date: 15 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The characteristics of hybrid three-arm coupler, which consists of the middle long range surface plasmon polariton waveguide and two outside conventional dielectric waveguides, are analyzed numerically with finite element method. Since the middle arm can only transfer the TM mode from one dielectric arm to the other one, this structure is promising for realizing integrated polarization splitter. Compared with the two-arm hybrid coupler, the loss of three-arm hybrid coupler based device can be reduced. Furthermore, different from conventional three-arm dielectric coupler, the authors find that the three-arm hybrid coupler with asymmetric structure can reach a much higher extinction ratio.
Show PACS
42.82.Et Waveguides, couplers, and arrays
42.79.Gn Optical waveguides and couplers
back to top
RSS Feeds

Effects of pulsed-excitation applied voltage rise time on argon metastable production efficiency in a high pressure dielectric barrier discharge

Robert J. Leiweke and Biswa N. Ganguly

Appl. Phys. Lett. 90, 241501 (2007); http://dx.doi.org/10.1063/1.2748324 (3 pages) | Cited 7 times

Online Publication Date: 11 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors have quantified the effect of pressure scaling on Ar metastable production efficiency in a dielectric barrier discharge with and without dielectric component losses. Estimates of the volume averaged deposited energy were performed for both short or long rise time voltage pulses, using the same total applied voltages of ∼ 10 and ∼ 150 ns, respectively. The metastable production efficiencies of long-pulse discharge exhibit smaller decrease over the 100–500 Torr pressure range, compared to those of the short-pulse one to the extent that the efficiency values and scaling for both cases are essentially the same within the experimental uncertainty.
Show PACS
52.50.Dg Plasma sources
52.80.Pi High-frequency and RF discharges
52.25.Os Emission, absorption, and scattering of electromagnetic radiation
52.70.Kz Optical (ultraviolet, visible, infrared) measurements

Xenon excimer emission from pulsed high-pressure capillary microdischarges

Byung-Joon Lee, Hasibur Rahaman, Isfried Petzenhauser, Klaus Frank, and Konstantinos P. Giapis

Appl. Phys. Lett. 90, 241502 (2007); http://dx.doi.org/10.1063/1.2748314 (3 pages) | Cited 5 times

Online Publication Date: 14 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Intense xenon vacuum ultraviolet (VUV) emission is observed from a high-pressure capillary cathode microdischarge in direct current operation, by superimposing a high-voltage pulse of 50 ns duration. Under stagnant gas conditions, the total VUV light intensity increases linearly with pressure from 400 to 1013 mbar for a fixed voltage pulse. At fixed pressure, however, the VUV light intensity increases superlinearly with voltage pulse height ranging from 08 to 2.8 kV. Gains in emission intensity are obtained by inducing gas flow through the capillary cathode, presumably because of excimer dimer survival due to gas cooling.
Show PACS
51.70.+f Optical and dielectric properties
52.80.Tn Other gas discharges
07.35.+k High-pressure apparatus; shock tubes; diamond anvil cells
back to top
RSS Feeds

Elastic and electronic properties of CoFe3N, RhFe3N, and IrFe3N from first principles

Zhijian Wu and Jian Meng

Appl. Phys. Lett. 90, 241901 (2007); http://dx.doi.org/10.1063/1.2748094 (3 pages) | Cited 8 times

Online Publication Date: 11 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
First principles calculations are performed to investigate the elastic and electronic properties of MFe3N (M = Co,Rh,Ir) at Pm-3m space group. The authors’ calculation indicates that the three MFe3N phases are metallic and mechanically stable. For RhFe3N, the calculated lattice parameter of 3.826 Å is in excellent agreement with the experimental value of 3.8292 Å. The three phases are ferromagnetic with the calculated magnetic moments per f.u. being 8.92μB for CoFe3N, 9.04μB for RhFe3N, and 8.50μB for IrFe3N. The unusually large B/G ratio from 2.47 for CoFe3N and 2.45 for RhFe3N to 1.81 for IrFe3N indicates that they are ductile.
Show PACS
81.40.Jj Elasticity and anelasticity, stress-strain relations
75.50.Dd Nonmetallic ferromagnetic materials
81.40.Lm Deformation, plasticity, and creep
71.20.Ps Other inorganic compounds
71.15.-m Methods of electronic structure calculations
61.66.Fn Inorganic compounds

Nearly full density Ni52.5Nb10Zr15Ti15Pt7.5 bulk metallic glass obtained by spark plasma sintering of gas atomized powders

Guoqiang Xie, Dmitri V. Louzguine-Luzgin, Hisamichi Kimura, and Akihisa Inoue

Appl. Phys. Lett. 90, 241902 (2007); http://dx.doi.org/10.1063/1.2748102 (3 pages) | Cited 33 times

Online Publication Date: 11 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Ni-based bulk metallic glasses (BMGs) with a large size were fabricated by spark plasma sintering (SPS) of a gas-atomized Ni52.5Nb10Zr15Ti15Pt7.5 glassy alloy powder. The structure and thermal stability of the sintered specimens as well as the interface characteristics between powder particles were investigated. The sintered glassy specimens with nearly 100% relative density were obtained by the SPS process at a sintering temperature of 773 K with a loading pressure of 600 MPa. It was achieved using relatively low sintering temperature, short holding time, and rapid cooling during the SPS process. The results suggest that the BMGs fabricated by the SPS process opens possibilities of application as structural materials offering excellent properties and satisfying large-size requirements.
Show PACS
81.05.Kf Glasses (including metallic glasses)
81.05.Bx Metals, semimetals, and alloys
81.20.Ev Powder processing: powder metallurgy, compaction, sintering, mechanical alloying, and granulation
61.43.Fs Glasses
61.43.Gt Powders, porous materials

Spontaneous formation of one-dimensional ripples in transit to highly ordered two-dimensional herringbone structures through sequential and unequal biaxial mechanical stretching

Pei-Chun Lin and Shu Yang

Appl. Phys. Lett. 90, 241903 (2007); http://dx.doi.org/10.1063/1.2743939 (3 pages) | Cited 35 times

Online Publication Date: 12 June 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors report the formation of various submicron wrinkle patterns and their transition from one-dimensional (1D) ripples to two-dimensional (2D) herringbone structures on poly(dimethylsiloxane) films. Using mechanical force they can separately control the amount and timing of strain applied to the substrate on both planar directions (either simultaneously or sequentially), which appears to be critical to maneuver the pattern formation in real time. They demonstrate reversible transitions from flat to 1D ripple, to ripple with bifurcation, to ripple/herringbone mixed features, and to well-controlled formation of a highly ordered zigzag-based 2D herringbone structures.
Show PACS
64.70.K- Solid-solid transitions
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
Page 1 of 5 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close