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

26 Nov 2001

Volume 79, Issue 22, pp. 3561-3731

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

Passive microring-resonator-coupled lasers

Bin Liu, Ali Shakouri, and John E. Bowers

Appl. Phys. Lett. 79, 3561 (2001); http://dx.doi.org/10.1063/1.1420585 (3 pages) | Cited 29 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this letter, a passive microring-resonator-coupled semiconductor laser structure is proposed. The weakly coupled high-Q microring resonator provides a strong mode-selection filter and could considerably extend the effective cavity length of a conventional Fabry–Perot laser. The side-mode suppression ratio, the linewidth and the frequency chirp of this laser are dramatically improved comparing to distributed feedback and distributed Bragg reflector lasers. © 2001 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.By Design of specific laser systems
42.55.Sa Microcavity and microdisk lasers
42.60.Fc Modulation, tuning, and mode locking

Nanocluster crystals of lacunary polyoxometalates as structure-design-flexible, inorganic nonlinear materials

Hidetoshi Murakami, Toshimasa Kozeki, Yuji Suzuki, Shingo Ono, Hideyuki Ohtake, Nobuhiko Sarukura, Eri Ishikawa, and Toshihiro Yamase

Appl. Phys. Lett. 79, 3564 (2001); http://dx.doi.org/10.1063/1.1419230 (3 pages) | Cited 13 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Lacunary polyoxometalates, large inorganic, structure-design-flexible, nanocluster crystals are found to have higher optical nonlinearity than KH2PO4 by the powder second-harmonic-generation method. Moreover, the capability of generating ultraviolet radiation down to around 300 nm is found. The basic criteria to design the high nonlinearity are also discovered by the reduction of the molecular symmetry. © 2001 American Institute of Physics.
Show PACS
42.70.Mp Nonlinear optical crystals
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation

Space-selective valence state manipulation of transition metal ions inside glasses by a femtosecond laser

Jianrong Qiu, Congshan Zhu, Takayuki Nakaya, Jinhai Si, Kazuo Kojima, Fumito Ogura, and Kazuyuki Hirao

Appl. Phys. Lett. 79, 3567 (2001); http://dx.doi.org/10.1063/1.1421640 (3 pages) | Cited 22 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the observation of space-selective oxidation of Mn2+ to Mn3+ in a transparent and colorless Mn and Fe ions codoped silicate glass at room temperature by using an 800-nm-femtosecond laser. Difference absorption spectrum of the glass after and before the irradiation of the focused infrared femtosecond pulsed laser showed that a portion of Mn2+ ions near the focused part of the laser beam inside the glass were oxidized to Mn3+ ions after the laser irradiation. Mn3+ ions were stable at the temperatures below 300 °C. It is suggested that Mn2+ ions act as hole trapping centers while Fe3+ ions as well as active sites in the glass matrix act as electron trapping centers. A promising application was demonstrated for the fabrication of three-dimensional colored image inside a transparent material. © 2001 American Institute of Physics.
Show PACS
61.72.J- Point defects and defect clusters
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
78.30.Hv Other nonmetallic inorganics

High-performance InAs quantum-dot lasers near 1.3 μm

Y. Qiu, P. Gogna, S. Forouhar, A. Stintz, and L. F. Lester

Appl. Phys. Lett. 79, 3570 (2001); http://dx.doi.org/10.1063/1.1421428 (3 pages) | Cited 50 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
High-performance quantum dot (QD) lasers near 1.3 μm were fabricated using four stacks of InAs QDs embedded within strained InGaAs quantum wells as an active region and a reactive-ion-etched 5-μm-ridge waveguide design. For a 1.5-mm-long cavity QD laser, ground-state continuous-wave (cw) lasing has been achieved with a single facet output power of 15 mW at temperatures as high as 100 °C, while at room temperature having a differential quantum efficiency of 55% and a single facet output power of 50 mW. The characteristic temperature T0 for ground-state cw lasing is 78 K up to our temperature measurement limit of 100 °C. © 2001 American Institute of Physics.
Show PACS
42.60.By Design of specific laser systems
85.35.Be Quantum well devices (quantum dots, quantum wires, etc.)
42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings

Over 30-fold enhancement of light extraction from free-standing photonic crystal slabs with InGaAs quantum dots at low temperature

H. Y. Ryu, Y. H. Lee, R. L. Sellin, and D. Bimberg

Appl. Phys. Lett. 79, 3573 (2001); http://dx.doi.org/10.1063/1.1420405 (3 pages) | Cited 42 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Highly efficient extraction of photoluminescence is observed from two-dimensional photonic crystal slabs employing InGaAs quantum dots as active material. The introduction of quantum dots reduces diffusion of carriers and thereby suppresses the surface recombination at the air-hole sidewalls of the photonic crystal. Around the normalized frequency of 0.7, over thirty-fold enhancement of the photoluminescence extraction is achieved at 78 K, indicating strong coupling to leaky modes of the free-standing photonic crystal slab. In addition, when the photoluminescence spectra overlaps with a photonic band gap, enhanced light extraction originating from the photonic band gap is observed experimentally. © 2001 American Institute of Physics.
Show PACS
78.67.Hc Quantum dots
78.55.Cr III-V semiconductors
73.63.Kv Quantum dots
42.70.Qs Photonic bandgap materials

Polymeric waveguide wavelength filters using electron-beam direct writing

W. H. Wong and E. Y. B. Pun

Appl. Phys. Lett. 79, 3576 (2001); http://dx.doi.org/10.1063/1.1421229 (3 pages) | Cited 25 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Polymeric waveguide wavelength filters based on a low-loss negative tone epoxy Novolak resin polymer have been fabricated using electron-beam direct writing. Both the waveguides and the gratings were exposed simultaneously, which effectively eliminate the alignment errors that can be generated during fabrication. A first-order Bragg grating around 1550 nm wavelength was used, and a transmission peak of −27 dB was obtained with a 5 mm long grating length, corresponding to >99% reflection. The 3 dB transmission bandwidth was found to be ∼ 0.8 nm and the 10 dB bandwidth was ∼ 1.0 nm. Dependence of the Bragg wavelength on electron-beam dosage and waveguide width was also investigated.© 2001 American Institute of Physics.
Show PACS
42.79.Ci Filters, zone plates, and polarizers
42.70.Jk Polymers and organics
42.79.Dj Gratings
42.86.+b Optical workshop techniques
42.82.Et Waveguides, couplers, and arrays

Enhanced transmission through photonic-crystal-based bent waveguides by bend engineering

Jürgen Moosburger, Martin Kamp, Alfred Forchel, Ségolène Olivier, Henri Benisty, Claude Weisbuch, and Ursula Oesterle

Appl. Phys. Lett. 79, 3579 (2001); http://dx.doi.org/10.1063/1.1421087 (3 pages) | Cited 20 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have studied the transmission of light through two-dimensional photonic-crystal-based waveguides with two 60° bends. The waveguides consist of three or five missing rows of holes inside a triangular photonic crystal block fabricated on an AlGaAs/GaAs waveguide structure. Fine tuning of the bend design results in a severe impact on the transmission behavior, leading to losses as low as 1.1 dB/bend. Measurements of losses in the bends were performed by a comparison with a straight guide of identical length. © 2001 American Institute of Physics.
Show PACS
42.70.Qs Photonic bandgap materials
42.82.Et Waveguides, couplers, and arrays

Monolithic intracavity laser-modulator device fabrication using postgrowth processing of 1.55 μm heterostructures

V. Aimez, J. Beauvais, J. Beerens, S. L. Ng, and B. S. Ooi

Appl. Phys. Lett. 79, 3582 (2001); http://dx.doi.org/10.1063/1.1421234 (3 pages) | Cited 9 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this letter, we present the attractive characteristics of a fabrication method based on quantum-well intermixing induced by low energy ion implantation for the realization of photonic integrated circuits on GaInAsP–InP heterostructures. Intracavity electro-absorption modulators monolithically integrated with laser devices were fabricated, using this postgrowth technique. The modulator section of the integrated devices was blueshifted by 75 nm while keeping the laser section unshifted and preserving very low values of the lasing threshold current density. Modulation depths in excess of 10 dB/V at 1.55 μm were obtained on these integrated devices which incorporate both a modulator and a laser. © 2001 American Institute of Physics.
Show PACS
42.82.Cr Fabrication techniques; lithography, pattern transfer
85.35.Be Quantum well devices (quantum dots, quantum wires, etc.)
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.55.Px Semiconductor lasers; laser diodes
42.79.Hp Optical processors, correlators, and modulators

Modified spontaneous emission in erbium-doped SiO2 spherical colloids

M. J. A. de Dood, L. H. Slooff, A. Polman, A. Moroz, and A. van Blaaderen

Appl. Phys. Lett. 79, 3585 (2001); http://dx.doi.org/10.1063/1.1419033 (3 pages) | Cited 16 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Spherical SiO2 colloids with two different diameters (175 nm, 340 nm) were doped with erbium at different concentrations. The spheres show sharply peaked photoluminescence centered at 1.535 μm, due to intra-4f transitions in Er3+. From measurements of the Er decay rate for different Er concentrations the decay rate of isolated Er ions (i.e., in absence of concentration quenching) was determined for the two colloid diameters. The data were compared to spontaneous emission rates derived from calculations of the local optical density of states in the colloids. The calculation predicts a large difference in the spontaneous emission rate for both colloid sizes (61 vs 40 s−1), in perfect agreement with the measured data. © 2001 American Institute of Physics.
Show PACS
78.55.Hx Other solid inorganic materials
71.55.Ht Other nonmetals
82.70.Dd Colloids
back to top
RSS Feeds

A mechanism for the multiple atomic configurations of inversion domain boundaries in GaN layers grown on Si(111)

A. M. Sanchez, G. Nouet, P. Ruterana, F. J. Pacheco, S. I. Molina, and R. Garcia

Appl. Phys. Lett. 79, 3588 (2001); http://dx.doi.org/10.1063/1.1396322 (3 pages) | Cited 10 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Atomic structure investigation has been carried out on inversion domain boundaries in GaN layer grown on Si(111) by molecular-beam epitaxy. The comparison of the stacking sequences between simulated and experimental high resolution electron microscopy images shows the existence of two different atomic configurations for the inversion domain boundaries: the Holt model coexists with the V model inside the same layers. A mechanism allowing the switch from one model to the other by the interaction with the I1 stacking fault is proposed. © 2001 American Institute of Physics.
Show PACS
68.55.-a Thin film structure and morphology
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.72.Nn Stacking faults and other planar or extended defects

First step towards the growth of single-crystal oxides on Si: Formation of a two-dimensional crystalline silicate on Si(001)

Y. Liang, S. Gan, and M. Engelhard

Appl. Phys. Lett. 79, 3591 (2001); http://dx.doi.org/10.1063/1.1415372 (3 pages) | Cited 26 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have investigated the structural and chemical properties of reconstructed Sr/Si(001) surfaces at different Sr coverages using low energy electron diffraction, x-ray photoelectron spectroscopy, and scanning tunneling microscopy. The results show that upon low temperature oxidation and subsequent UHV annealing of the Sr/Si(001)-(2×1) surface, a crystalline Sr2SiO4 silicate-like layer formed. Using this layer as a template, single-crystal SrO thin films were grown on Si(001) substrates. Our results provide microscopic and spectroscopic evidence of the formation of a uniform, stable, two-dimensional crystalline silicate that can be used for growth of single-crystal oxides on Si(001) substrates. © 2001 American Institute of Physics.
Show PACS
81.65.Mq Oxidation
68.35.B- Structure of clean surfaces (and surface reconstruction)
79.60.Jv Interfaces; heterostructures; nanostructures
61.72.Cc Kinetics of defect formation and annealing

Concurrent x-ray diffractometer for high throughput structural diagnosis of epitaxial thin films

M. Ohtani, T. Fukumura, M. Kawasaki, K. Omote, T. Kikuchi, J. Harada, A. Ohtomo, M. Lippmaa, T. Ohnishi, D. Komiyama, R. Takahashi, Y. Matsumoto, and H. Koinuma

Appl. Phys. Lett. 79, 3594 (2001); http://dx.doi.org/10.1063/1.1415402 (3 pages) | Cited 25 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have developed a concurrent x-ray diffractometer that concurrently measures spatially resolved x-ray diffraction (XRD) spectra of epitaxial thin films integrated on a substrate. A convergent x-ray is focused into stripe on a substrate and the diffracted beam is detected with a two-dimensional x-ray detector. The obtained snapshot image represents a mapping of XRD intensity with the axes of the diffraction angle and the position in the sample. In addition to the parallel XRD measurements of thin films with various compositions and structures, two-dimensional spatial mapping of XRD peak with a resolution of ∼ 100 μm is demonstrated. This technique will provide us a high throughput characterization method of various devices composed of epitaxial films.© 2001 American Institute of Physics.
Show PACS
61.05.cp X-ray diffraction
07.85.Jy Diffractometers
68.55.-a Thin film structure and morphology

Mechanical stresses upon crystallization in phase change materials

T. P. Leervad Pedersen, J. Kalb, W. K. Njoroge, D. Wamwangi, M. Wuttig, and F. Spaepen

Appl. Phys. Lett. 79, 3597 (2001); http://dx.doi.org/10.1063/1.1415419 (3 pages) | Cited 62 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Crystallization processes in different Te alloys, employed in phase change materials for optical data storage, have been investigated by in situ mechanical stress measurements. Upon crystallization a considerable stress buildup is observed, which scales with the volume change upon crystallization. Nevertheless the observed stress change only corresponds to approximately 9% of the stress estimated for a purely elastic transformation. Further evidence of stress relief phenomena comes from the temperature dependence of the stress in the crystalline and amorphous states. Ultrathin dielectric layers have a profound influence on the crystallization process as evidenced by simultaneous optical reflectance and mechanical stress measurements. This observation can be explained by heterogeneous nucleation of crystallites at the interface between the dielectric layer and the phase change film. © 2001 American Institute of Physics.
Show PACS
64.70.K- Solid-solid transitions
42.79.Vb Optical storage systems, optical disks

Band gap bowing and exciton localization in strained cubic InxGa1−xN films grown on 3C-SiC (001) by rf molecular-beam epitaxy

S. F. Chichibu, M. Sugiyama, T. Kuroda, A. Tackeuchi, T. Kitamura, H. Nakanishi, T. Sota, S. P. DenBaars, S. Nakamura, Y. Ishida, and H. Okumura

Appl. Phys. Lett. 79, 3600 (2001); http://dx.doi.org/10.1063/1.1421082 (3 pages) | Cited 12 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Spontaneous emission mechanisms in InGaN alloys were studied by determining the effective band gap energies using photoluminescence excitation spectroscopy and static and time-resolved photoluminescence (PL) measurements on fully strained cubic (c-) InxGa1−xN films on c-GaN templates, which were grown by rf molecular-beam epitaxy on smaller lattice-mismatched 3C-SiC (001) substrates prepared on Si (001). The c-InxGa1−xN alloys exhibited large band gap bowing. The PL decay dynamics showed that the emission is due to recombination of localized excitons, the same as in the case of hexagonal InGaN. The c-InxGa1−xN exhibited a larger Stokes-like shift and a larger localization depth, showing that the material’s inhomogeneity is much enhanced compared to that of the hexagonal polytype. © 2001 American Institute of Physics.
Show PACS
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
73.20.Fz Weak or Anderson localization
73.20.At Surface states, band structure, electron density of states
71.35.-y Excitons and related phenomena
78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors
78.47.-p Spectroscopy of solid state dynamics

From two-dimensional heterogeneous nucleation-induced kinetic roughening to needle-like pattern formation

Xiang Y. Liu

Appl. Phys. Lett. 79, 3603 (2001); http://dx.doi.org/10.1063/1.1421417 (3 pages) | Cited 2 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report in this letter a special type of kinetic roughening at a growing crystal face induced by foreign particles. At relatively low supercoolings, the faceted growth of the {110} faces of naphthalene crystals from its melt reveals a transition from smooth to rough growth when foreign particles are in contact with the crystal surface, and followed by an increase in the growth rate. This is due to the vanishing of the two-dimensional nucleation barrier at the particle contact area, which gives rise to the formation of a needle-like pattern formation at the contact point. At high supercoolings, the particle-induced kinetic roughening is suppressed. The particle-induced kinetic roughening was also observed at the {110} faces of n-C21H44 crystals. © 2001 American Institute of Physics.
Show PACS
81.10.Aj Theory and models of crystal growth; physics and chemistry of crystal growth, crystal morphology, and orientation
68.35.Rh Phase transitions and critical phenomena
64.60.Q- Nucleation
68.35.Ct Interface structure and roughness
81.10.Fq Growth from melts; zone melting and refining

Dry thermal oxidation of a graded SiGe layer

Y. S. Lim, J. S. Jeong, J. Y. Lee, H. S. Kim, H. K. Shon, H. K. Kim, and D. W. Moon

Appl. Phys. Lett. 79, 3606 (2001); http://dx.doi.org/10.1063/1.1415373 (3 pages) | Cited 7 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A method for the dry thermal oxidation of a strained SiGe layer is proposed. By oxidation of a graded Si1−xGex layer, the effect of Ge pileup was significantly reduced and the undesirable strain relaxation by defect formation is prohibited. After oxidation, the oxidized SiGe layer was homogenized by postannealing process, and thereby a SiO2/SiGe interface with good structural properties was obtained. During postannealing, the homogenization was significantly enhanced by strain-induced diffusion, and it was clearly proved by the uphill diffusion. This result can propose an alternative oxidation method of strained SiGe/Si heterostructures. © 2001 American Institute of Physics.
Show PACS
81.65.Mq Oxidation
61.72.Cc Kinetics of defect formation and annealing
68.35.Fx Diffusion; interface formation

Composite diamond-like carbon and silicon carbide tips grown on oblique-cut Si(111) substrates

W. Y. Yeh, J. Hwang, A. P. Lee, C. S. Kou, and H. Chang

Appl. Phys. Lett. 79, 3609 (2001); http://dx.doi.org/10.1063/1.1421427 (3 pages) | Cited 6 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A diamond-like carbon (DLC) and silicon carbide (SiC) composite tip structure was successfully deposited on an oblique-cut Si(111) substrate of terrace width less than 21.1 Å. The DLC morphology depended on the Si(111) terrace width in the oblique-cut Si(111) surface. A continuous and dense DLC film started to form on the Si(111) substrate of terrace width higher than 27.8 Å. The density of the DLC/SiC composite tip also depended on the terrace width. The DLC films on the Si(111) with or without oblique cut had about the same Raman characteristics regardless of their different morphologies. The formation mechanism of the DLC/SiC tip structure was discussed. © 2001 American Institute of Physics.
Show PACS
81.05.U- Carbon/carbon-based materials
68.55.-a Thin film structure and morphology
68.55.A- Nucleation and growth
85.45.Fd Field emission displays (FEDs)
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.37.Hk Scanning electron microscopy (SEM) (including EBIC)
68.35.Ct Interface structure and roughness

Optical constants of wurtzite ZnS thin films determined by spectroscopic ellipsometry

H. C. Ong and R. P. H. Chang

Appl. Phys. Lett. 79, 3612 (2001); http://dx.doi.org/10.1063/1.1419229 (3 pages) | Cited 48 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The complex dielectric functions of wurtzite ZnS thin films grown on (0001) Al2O3 have been determined by using spectroscopic ellipsometry over the spectral range of 1.33–4.7 eV. Below the band gap, the refractive index n is found to follow the first-order Sellmeir dispersion relationship n2(λ) = 1+2.22λ2/(λ2−0.0382). Strong and well-defined free excitonic features located above the band edge are clearly observed at room temperature. The intrinsic optical parameters of wurtzite ZnS such as band gaps and excitonic binding energies have been determined by fitting the absorption spectrum using a modified Elliott expression together with Lorentizan broadening. Both parameters are found to be larger than their zinc blende counterparts. © 2001 American Institute of Physics.
Show PACS
78.66.Hf II-VI semiconductors
77.22.Ch Permittivity (dielectric function)
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
71.35.Cc Intrinsic properties of excitons; optical absorption spectra
77.55.-g Dielectric thin films
78.40.Fy Semiconductors

Surface morphology evolution during the overgrowth of large InAs–GaAs quantum dots

P. B. Joyce, T. J. Krzyzewski, G. R. Bell, and T. S. Jones

Appl. Phys. Lett. 79, 3615 (2001); http://dx.doi.org/10.1063/1.1420579 (3 pages) | Cited 51 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The effects of GaAs overgrowth on the structural properties of large low-growth-rate InAs quantum dots (LGR-QDs) grown on GaAs(001) are examined using in situ scanning tunneling microscopy. Strongly anisotropic surface diffusion produces a characteristic valley-ridge structure above the LGR-QDs and the surface is not planarized even after a cap thickness >400 Å. The evolution of surface morphology proceeds very differently to the case of smaller conventional growth rate QDs capped under the same conditions, due to the different initial strain states of the QDs.© 2001 American Institute of Physics.
Show PACS
68.65.Hb Quantum dots (patterned in quantum wells)
81.07.Ta Quantum dots
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.35.B- Structure of clean surfaces (and surface reconstruction)
68.35.Fx Diffusion; interface formation
81.05.Ea III-V semiconductors

Multipeak negative-differential-resistance device by combining single-electron and metal–oxide–semiconductor transistors

Hiroshi Inokawa, Akira Fujiwara, and Yasuo Takahashi

Appl. Phys. Lett. 79, 3618 (2001); http://dx.doi.org/10.1063/1.1421085 (3 pages) | Cited 13 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A multipeak negative-differential-resistance device is proposed. The device comprises a single-electron transistor (SET) and a metal–oxide–semiconductor field-effect transistor (MOSFET), and can, in principle, generate an infinite number of current peaks. Operation of the proposed device is verified at 27 K with a SET fabricated by the pattern-dependent oxidation process and a MOSFET on the same silicon-on-insulator wafer. Six current peaks and a peak-to-valley current ratio of 2.1 are obtained, and multiple-valued memory operation is successfully demonstrated. © 2001 American Institute of Physics.
Show PACS
85.35.Gv Single electron devices
85.30.Tv Field effect devices

Destabilization of dislocation dipole at high velocity

Jian Wang, C. H. Woo, and Hanchen Huang

Appl. Phys. Lett. 79, 3621 (2001); http://dx.doi.org/10.1063/1.1421425 (3 pages) | Cited 8 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Under mechanical deformation of very high strain rates, it is expected that dislocations may move very fast (being subsonic, transonic, or even supersonic). As a result, two dislocations may approach each other at high velocities. Our earlier analyses of linear elasticity indicate that a dipole is destabilized when the approaching velocity is high enough—even below the speed of sound. In this letter, using the molecular dynamics method, we demonstrate that a dipole indeed can be destabilized above a critical velocity, and stable below that. © 2001 American Institute of Physics.
Show PACS
61.72.Lk Linear defects: dislocations, disclinations
62.20.D- Elasticity

Melting temperature effects on the size of ion-induced craters

K. Nordlund, K. O. E. Henriksson, and J. Keinonen

Appl. Phys. Lett. 79, 3624 (2001); http://dx.doi.org/10.1063/1.1421237 (3 pages) | Cited 11 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Recent work on the sizes of craters produced by ion impacts of solids has shown that the size of the crater scales with the inverse square of the cohesive energy. This observation is in contrast to the size of craters produced in macroscopic impacts, which scale directly with the inverse of the cohesive energy. It has relied on the assumption that the melting temperature is proportional to the cohesive energy. Using computer simulations, we now show that the size scales in fact with the inverse of the product of the melting temperature and cohesive energy. This provides direct proof that the reason to the different behavior of macroscopic and ion-induced cratering is flow of the liquid produced by the ions. © 2001 American Institute of Physics.
Show PACS
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces
64.70.D- Solid-liquid transitions
68.35.Md Surface thermodynamics, surface energies

Electric field tuning of a stop band in a reflection spectrum of synthetic opal infiltrated with nematic liquid crystal

Y. Shimoda, M. Ozaki, and K. Yoshino

Appl. Phys. Lett. 79, 3627 (2001); http://dx.doi.org/10.1063/1.1421080 (3 pages) | Cited 77 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Electric field tuning of an optical stop band in a reflection spectrum is demonstrated in a synthetic opal thin film infiltrated with liquid crystal. The reflection peak of the opal shifts upon the application of the electric field, and this is based on the refractive index change caused by molecular reorientation upon application of a field. The dynamic response of the stop band shift was also studied, and fast response of the order of microsecond was observed. © 2001 American Institute of Physics.
Show PACS
42.70.Qs Photonic bandgap materials
42.70.Df Liquid crystals
61.30.Gd Orientational order of liquid crystals; electric and magnetic field effects on order
77.84.Nh Liquids, emulsions, and suspensions; liquid crystals
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
61.72.Qq Microscopic defects (voids, inclusions, etc.)
78.40.-q Absorption and reflection spectra: visible and ultraviolet
78.20.Jq Electro-optical effects

Reconstruction defects on partial dislocations in semiconductors

João F. Justo and Lucy V. C. Assali

Appl. Phys. Lett. 79, 3630 (2001); http://dx.doi.org/10.1063/1.1421623 (3 pages) | Cited 1 time

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Using ab initio total energy calculations, we investigated the structural and electronic properties of reconstruction defects, or antiphase defects, in the core of a 30° partial dislocation in silicon and gallium arsenide. In GaAs, we identified two different reconstruction defects in the dislocation cores, corresponding to a Ga undercoordinated atom, and an As undercoordinated atom. Formation energies of these reconstruction defects were compared to experimental results on the concentration of electrically active centers in deformed semiconducting materials. © 2001 American Institute of Physics.
Show PACS
71.15.Nc Total energy and cohesive energy calculations
61.72.Bb Theories and models of crystal defects
71.15.-m Methods of electronic structure calculations
68.35.B- Structure of clean surfaces (and surface reconstruction)

High emissivity of a rough Pr2NiO4 coating

B. Rousseau, M. Chabin, P. Echegut, A. Sin, F. Weiss, and P. Odier

Appl. Phys. Lett. 79, 3633 (2001); http://dx.doi.org/10.1063/1.1420780 (3 pages) | Cited 13 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A rough and thick film of doped praseodymium nickel oxide (Pr2NiO4+δ) has been obtained by combining the spray pyrolysis deposition technique with rapid thermal annealing process. The precursors are nitrate solutions. Spectral emissivity measurements from the far infrared up to the midinfrared region at T = 1000 K show the strong black body character of the film. This feature is well suited to the thermal efficiency of an industrial infrared ceramic radiant plate. © 2001 American Institute of Physics.
Show PACS
61.72.Cc Kinetics of defect formation and annealing
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
78.30.Hv Other nonmetallic inorganics
78.66.Nk Insulators
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
Page 1 of 3 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close