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

2 Feb 2009

Volume 94, Issue 5, Articles (05xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 94, 059901 (2009); http://dx.doi.org/10.1063/1.3086725 (3 pages)

Yuta Tsukada, Tsuyoshi Honma, and Takayuki Komatsu
Enlarge Image | Read More
Page 1 of 4 Pages Next Page | Jump to Page
back to top
RSS Feeds

Extended high-order harmonics from laser-produced Cd and Cr plasmas

R. A. Ganeev, M. Suzuki, M. Baba, and H. Kuroda

Appl. Phys. Lett. 94, 051101 (2009); http://dx.doi.org/10.1063/1.3072353 (3 pages) | Cited 8 times

Online Publication Date: 2 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We observed the extended harmonic spectra generated in the Cd and Cr plasmas. The mechanism of harmonic extension was attributed to the harmonic generation in doubly charged particles and the influence of broadband ionic resonances in the range of 20–25 nm. The extension of harmonic cutoff up to the 73rd (Cd) and 83rd (Cr) orders was achieved.
Show PACS
52.50.Jm Plasma production and heating by laser beams (laser-foil, laser-cluster, etc.)

Experimental observation of whispering gallery modes in sector disk lasers

A. M. Monakhov, V. V. Sherstnev, A. P. Astakhova, Yu. P. Yakovlev, G. Boissier, R. Teissier, and A. N. Baranov

Appl. Phys. Lett. 94, 051102 (2009); http://dx.doi.org/10.1063/1.3075852 (3 pages) | Cited 6 times

Online Publication Date: 2 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The existence of the whispering gallery modes in a sector disk resonator has been demonstrated theoretically and experimentally observed in a disk, half-disk, and quarter-disk semiconductor lasers. The half-disk and quarter-disk lasers are fabricated from 285 μm diameter disks emitted near 2.13 μm at room temperature with continuous wave threshold currents of 55–60 mA. Mode spacing in emission spectra of the half-disk lasers was the same as for the whole disk and doubled for the quarter disk as expected from the theoretical analysis. Half-disk lasers emit two parallel beams from the cleaved facet, while the two output beams are perpendicular in quarter-disk devices.
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

A thermal lens model including the Soret effect

Humberto Cabrera, Eloy Sira, Kareem Rahn, and Máximo García-Sucre

Appl. Phys. Lett. 94, 051103 (2009); http://dx.doi.org/10.1063/1.3078287 (3 pages) | Cited 4 times

Online Publication Date: 2 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this letter we generalize the thermal lens model to account for the Soret effect in binary liquid mixtures. This formalism permits the precise determination of the Soret coefficient in a steady-state situation. The theory is experimentally verified using the measured values in the ethanol/water mixtures. The time evolution of the Soret signal has been used to derive mass-diffusion times from which mass-diffusion coefficients were calculated.
Show PACS
66.10.cd Thermal diffusion and diffusive energy transport
66.10.cg Mass diffusion, including self-diffusion, mutual diffusion, tracer diffusion, etc.

Whispering gallery modes in micron-sized SrS:Eu octahedrons

Katleen Korthout, Philippe F. Smet, and Dirk Poelman

Appl. Phys. Lett. 94, 051104 (2009); http://dx.doi.org/10.1063/1.3078398 (3 pages) | Cited 8 times

Online Publication Date: 2 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Optical whispering gallery modes were observed in micron-sized SrS:Eu2+ octahedrons. Cathodoluminescence in a scanning electron microscope was used to evaluate the emission characteristics of individual octahedrons with various sizes. The resonance modes superposed on the orange Eu2+ broadband emission were explained by a plane wave model, taking the wavelength dispersion of the refractive index into account. The resonance modes occur in the three equatorial planes in the octahedrons, which were approximated by corner-cut square disks.
Show PACS
78.60.Hk Cathodoluminescence, ionoluminescence
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)

Fabry–Pérot-type enhancement in plasmonic visible nanosource

Marianne Consonni, Jérôme Hazart, and Gilles Lérondel

Appl. Phys. Lett. 94, 051105 (2009); http://dx.doi.org/10.1063/1.3039075 (3 pages)

Online Publication Date: 3 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Starting from thin film planar technology, we designed and fabricated a visible optical source that produces a localized bright spot with nanometric dimensions. The structure consists of exciting surface plasmons through the illumination of a subwavelength hole in a silver film and in confining them at the vicinity of the aperture by surrounding the hole of Bragg mirrors resonant with the plasmons generated. Both finite element method computations and experimental results evidence the performances of this device that could find applications, for example, in nanolithography or optical data storage.
Show PACS
78.66.Bz Metals and metallic alloys
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)
73.22.Lp Collective excitations
42.72.-g Optical sources and standards
78.68.+m Optical properties of surfaces

Two-photon excited whispering-gallery mode ultraviolet laser from an individual ZnO microneedle

G. P. Zhu, C. X. Xu, J. Zhu, C. G. Lv, and Y. P. Cui

Appl. Phys. Lett. 94, 051106 (2009); http://dx.doi.org/10.1063/1.3077011 (3 pages) | Cited 27 times

Online Publication Date: 3 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Wurtzite structural ZnO microneedles with hexagonal cross section were fabricated by vapor-phase transport method and an individual microneedle was employed as a lasing microcavity. Under excitation of a femtosecond pulse laser with 800 nm wavelength, the ultraviolet (UV) laser emission was obtained, which presented narrow linewidth and high Q value. The UV emission, resonant mechanism, and laser mode characteristics were discussed in detail. The results demonstrated that the UV laser originated from the whispering-gallery mode induced by two-photon absorption assisted by Rabi oscillation.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.By Design of specific laser systems

Tapered Sommerfeld wire terahertz near-field imaging

M. Awad, M. Nagel, and H. Kurz

Appl. Phys. Lett. 94, 051107 (2009); http://dx.doi.org/10.1063/1.3078278 (3 pages) | Cited 16 times

Online Publication Date: 3 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We explore the potential of tapered Sommerfeld wire waveguides for terahertz near-field imaging. The electric field confinement in the vicinity of the tapered wire tip is exploited to achieve subwavelength resolution. After coupling onto the Sommerfeld wire, terahertz pulses propagate as surface-plasmon waves along the waveguide and subsequently reflect at the imaging target surface. The reflected signal is then detected at the waveguide surface using a freestanding photoconductive terahertz probe. The resolution achieved is on the order of the tip diameter. This subwavelength resolution is demonstrated in a proof-of-principle experiment.
Show PACS
07.57.-c Infrared, submillimeter wave, microwave and radiowave instruments and equipment
84.40.Az Waveguides, transmission lines, striplines

Simultaneous generation and detection of ultrashort voltage pulses in low-temperature grown GaAs with below-bandgap laser pulses

Mark Bieler, Klaus Pierz, and Uwe Siegner

Appl. Phys. Lett. 94, 051108 (2009); http://dx.doi.org/10.1063/1.3078288 (3 pages) | Cited 1 time

Online Publication Date: 3 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present a method that allows for the simultaneous generation and detection of ultrashort voltage pulses, which propagate on a planar transmission line, in the same material with laser pulses of the same wavelength. The generation is accomplished by exciting band-tail states below the fundamental bandgap of a low-temperature grown GaAs layer, while the detection takes advantage of the electro-optic effect in the GaAs material. This simple scheme considerably enhances previous measurement techniques and is capable of generating and measuring frequencies exceeding 1 THz. The optimum wavelength for the combined generation and detection technique is found at ∼ 900 nm.
Show PACS
72.40.+w Photoconduction and photovoltaic effects
73.50.Pz Photoconduction and photovoltaic effects
78.66.Fd III-V semiconductors
78.20.Jq Electro-optical effects

Localized growth of InAs quantum dots on nanopatterned InP(001) substrates

Artur Turala, Philippe Regreny, Pedro Rojo-Romeo, and Michel Gendry

Appl. Phys. Lett. 94, 051109 (2009); http://dx.doi.org/10.1063/1.3078275 (3 pages) | Cited 3 times

Online Publication Date: 5 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present the method of site-controlled growth of InAs quantum dots on InP(001) by solid-source molecular beam epitaxy. InAs dots are positioned using nanopatterns realized by electron beam lithography and dry etching. We have obtained the localized InAs dots for InAs deposit thickness inferior to the critical thickness for the two-dimensional/three-dimensional growth mode transition measured on a flat InP surface, implying that the dots can be actively positioned at predefined nucleation sites. Photoluminescence results show the emission of localized InAs dots on patterns overgrown with a thin InP buffer layer, at a wavelength around 1.5 μm at room temperature.
Show PACS
68.65.Hb Quantum dots (patterned in quantum wells)
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors
81.16.Nd Micro- and nanolithography
81.16.Rf Micro- and nanoscale pattern formation

Monolithic integration of quantum dot containing microdisk microcavities coupled to air-suspended waveguides

Shinichi Koseki, Bingyang Zhang, Kristiaan De Greve, and Yoshihisa Yamamoto

Appl. Phys. Lett. 94, 051110 (2009); http://dx.doi.org/10.1063/1.3078522 (3 pages) | Cited 8 times

Online Publication Date: 5 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
GaAs microdisk microcavities coupled to monolithic air-suspended waveguide structures are fabricated with out-of-plane light coupling achieved via the grating couplers monolithically integrated in the input and output ports. Photoluminescence signal of the whispering gallery modes is extracted from the grating couplers through the waveguide. Quality factors of modes are obtained through a transmission measurement with quality factors of up to 9500 and transmission depth of ΔT = 35%.
Show PACS
42.82.Et Waveguides, couplers, and arrays
42.79.Dj Gratings
85.40.-e Microelectronics: LSI, VLSI, ULSI; integrated circuit fabrication technology
78.55.-m Photoluminescence, properties and materials

Wavelength selection by dielectric-loaded plasmonic components

Tobias Holmgaard, Zhuo Chen, Sergey I. Bozhevolnyi, Laurent Markey, Alain Dereux, Alexey V. Krasavin, and Anatoly V. Zayats

Appl. Phys. Lett. 94, 051111 (2009); http://dx.doi.org/10.1063/1.3078235 (3 pages) | Cited 37 times

Online Publication Date: 6 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Fabrication, characterization, and modeling of waveguide-ring resonators and in-line Bragg gratings for wavelength selection in the telecommunication range are reported utilizing dielectric-loaded surface plasmon-polariton waveguides. The devices were fabricated by depositing subwavelength-sized polymer ridges on a smooth gold film using industrially compatible large-scale UV photolithography. We demonstrate efficient and compact wavelength-selective filters, including waveguide-ring resonators with an insertion loss of ∼ 2 dB and a footprint of only 150 μm2 featuring narrow bandwidth ( ∼ 20 nm) and high contrast ( ∼ 13 dB) features in the transmission spectrum. The performance of the components is found in good agreement with the results obtained by full vectorial three-dimensional finite element simulations.
Show PACS
42.79.Gn Optical waveguides and couplers
42.79.Dj Gratings
42.79.Ci Filters, zone plates, and polarizers
42.82.Cr Fabrication techniques; lithography, pattern transfer
84.40.-x Radiowave and microwave (including millimeter wave) technology

High sensitivity pulsed laser vibrometer and its application as a laser microphone

Chen-Chia Wang, Sudhir Trivedi, Feng Jin, V. Swaminathan, Ponciano Rodriguez, and Narasimha S. Prasad

Appl. Phys. Lett. 94, 051112 (2009); http://dx.doi.org/10.1063/1.3078520 (3 pages) | Cited 3 times

Online Publication Date: 6 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We experimentally demonstrate a high sensitivity pulsed laser vibrometer that is capable of detecting optically rough surfaces vibrating with the displacement value of 75 pm as well as its application as a laser microphone. By directing the probe light beam repeatedly onto the vibrating diaphragm and/or pressure sensing interface, the sensitivity of the pulsed laser vibrometer in detecting the displacement of the vibrating diaphragm is significantly improved down to an estimated value of less than 4 pm In this paper, we present the principles of operation of this new kind of laser microphone together with experimental validations.
Show PACS
42.62.Eh Metrological applications; optical frequency synthesizers for precision spectroscopy
07.10.-h Mechanical instruments and equipment

Magneto-optical waveguides made of cobalt ferrite nanoparticles embedded in silica/zirconia organic-inorganic matrix

Fadi Choueikani, François Royer, Damien Jamon, Ali Siblini, Jean Jacques Rousseau, Sophie Neveu, and Jamal Charara

Appl. Phys. Lett. 94, 051113 (2009); http://dx.doi.org/10.1063/1.3079094 (3 pages) | Cited 7 times

Online Publication Date: 6 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This paper describes a way to develop magneto-optical waveguides via sol-gel process. They are made of cobalt ferrite nanoparticles embedded in a silica/zirconia matrix. Thin films are coated on glass substrate using the dip-coating technique. Annealing and UV treatment are applied to finalize sample preparation. Therefore, planar waveguides combining magneto-optical properties with a low refractive index (≈1,5) are obtained. M-lines and free space ellipsometry measurements show a specific Faraday rotation of 250°/cm and a modal birefringence of 1×10−4 at 820 nm. Thus, the mode conversion efficiency can reach a maximum value around 56%.
Show PACS
42.79.Gn Optical waveguides and couplers
42.82.Et Waveguides, couplers, and arrays
85.70.Sq Magnetooptical devices
78.20.Ls Magneto-optical effects
78.20.Fm Birefringence
75.50.Tt Fine-particle systems; nanocrystalline materials

Broadband and omnidirectional antireflection from conductive indium-tin-oxide nanocolumns prepared by glancing-angle deposition with nitrogen

C. H. Chang, Peichen Yu, and C. S. Yang

Appl. Phys. Lett. 94, 051114 (2009); http://dx.doi.org/10.1063/1.3079329 (3 pages) | Cited 26 times

Online Publication Date: 6 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Characteristic formation of highly oriented indium-tin-oxide (ITO) nanocolumns is demonstrated using electron-beam evaporation with an obliquely incident nitrogen flux. The nanocolumn material exhibits broadband and omnidirectional antireflective characteristics up to an incidence angle of 70° for the 350–900 nm wavelength range for both s- and p-polarizations. Calculations based on a rigorous coupled-wave analysis indicate that the superior antireflection arises from the tapered column profiles which collectively function as a gradient-index layer. Since the nanocolumns have a preferential growth direction which follows the incident vapor flux, the azimuthal and polarization dependence of reflectivities are also investigated. The single ITO nanocolumn layer can function as antireflection contacts for light emitting diodes and solar cells.
Show PACS
78.67.Bf Nanocrystals, nanoparticles, and nanoclusters
81.07.Bc Nanocrystalline materials
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy

Frequency narrowing of a 25 W broad area diode laser

J. F. Sell, W. Miller, D. Wright, B. V. Zhdanov, and R. J. Knize

Appl. Phys. Lett. 94, 051115 (2009); http://dx.doi.org/10.1063/1.3079418 (3 pages) | Cited 3 times

Online Publication Date: 6 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on the spectral narrowing of a high powered (25 W) broad area diode laser using an external cavity with a holographic diffraction grating. In a Littman–Metcalf configuration, the external cavity is able to reduce the linewidth of the diode laser to primarily a single longitudinal mode (1.8 MHz) for output powers of ≤ 10 W at 852 nm. Many physics applications could benefit from such high powered, narrow linewidth lasers; however both the frequency stability and the spatial profile of the output beam show room for improvement.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.40.Eq Holographic optical elements; holographic gratings

Rapid passage effects in nitrous oxide induced by a chirped external cavity quantum cascade laser

J. H. van Helden, R. Peverall, G. A. D. Ritchie, and R. J. Walker

Appl. Phys. Lett. 94, 051116 (2009); http://dx.doi.org/10.1063/1.3079420 (3 pages) | Cited 6 times

Online Publication Date: 6 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A widely tunable pulsed external cavity quantum cascade laser operating around 8 μm has been used to make rotationally resolved measurements of rapid passage effects in the absorption spectrum of N2O. Rapid passage signals as a function of laser power and N2O pressure are presented. Comparisons are drawn with measurements performed on the same transition with a standard distributed feedback quantum cascade laser. The initial observations on rapid passage effects induced with an external cavity quantum cascade laser show that such high power, widely tunable radiation sources may find applications in both nonlinear optics and optical sensing experiments.
Show PACS
33.20.Ea Infrared spectra
33.15.Mt Rotation, vibration, and vibration-rotation constants

Low-order distributed feedback optofluidic dye laser with reduced threshold

Wuzhou Song, Andreas E. Vasdekis, Zhenyu Li, and Demetri Psaltis

Appl. Phys. Lett. 94, 051117 (2009); http://dx.doi.org/10.1063/1.3079799 (3 pages) | Cited 22 times

Online Publication Date: 6 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the demonstration of low order distributed feedback (DFB) optofluidic dye lasers with reduced threshold. The laser chips were realized in polydimethylsiloxane using replica molding with two masters. A comparison between first, second, and third order DFB dye lasers was performed, while the second order DFB dye laser exhibited the lowest pump threshold of 78 nJ/pulse. Compared to previous reports on higher order Bragg grating structures, the pump threshold in this work is approximately 30-fold lower than the state of the art due to the reduction in the cavity losses and the more efficient pumping configuration.
Show PACS
42.55.Mv Dye lasers
42.60.By Design of specific laser systems
42.79.Dj Gratings
back to top
RSS Feeds

Charge trapping induced by plasma in alumina electrode surface investigated by thermoluminescence and optically stimulated luminescence

P. F. Ambrico, M. Ambrico, L. Schiavulli, T. Ligonzo, and V. Augelli

Appl. Phys. Lett. 94, 051501 (2009); http://dx.doi.org/10.1063/1.3076122 (3 pages) | Cited 3 times

Online Publication Date: 3 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The plasma of a dielectric barrier discharge can fill traps in the alumina that cover the electrode. Trap energies and lifetimes are estimated by thermoluminescence and optically stimulated luminescence. Comparison with similar results for traps created by other radiation sources clarifies the mechanisms regulating this effect. Alumina’s trap energies are approximately 1 eV, and the traps remain active for several days after plasma exposure. These results could be important to keep dielectric barrier discharge plasmas uniform since a trapped charge can be an electron reservoir.
Show PACS
52.40.Hf Plasma-material interactions; boundary layer effects
78.60.Kn Thermoluminescence
78.55.Hx Other solid inorganic materials
52.80.-s Electric discharges
back to top
RSS Feeds

Atomistic simulation of a NiZr model metallic glass under hydrostatic pressure

Yu-zheng Guo and Mo Li

Appl. Phys. Lett. 94, 051901 (2009); http://dx.doi.org/10.1063/1.3077862 (3 pages) | Cited 4 times

Online Publication Date: 2 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Compressive behavior of a model NiZr metallic glass under hydrostatic pressure is simulated using molecular dynamics. The equation of state obtained exhibits two distinct regimes, one at low and the other at high pressure, along with an intermediate region in between. The densification is associated with topological rearrangement of atoms at low pressure and hard-sphere-like compaction dictated by the strong interatomic repulsion at high pressure. Different from many isotropic materials, the atomic rearrangement in the metallic glass during compression is accompanied by strong local topological structure change and chemical short-range (re)ordering. The possibility of a pressure-induced phase transition is briefly discussed.
Show PACS
61.43.Fs Glasses
64.30.Jk Equations of state of nonmetals
64.70.kj Glasses
62.50.-p High-pressure effects in solids and liquids

High external emission efficiency in intentionally ordered GaInP/GaAs structures

J. S. Song, S. H. Seo, Y. C. Choi, H. S. Song, Y. H. Chang, M. H. Oh, D. C. Oh, T. Yao, J. H. Chang, C. S. Han, and K. W. Koo

Appl. Phys. Lett. 94, 051902 (2009); http://dx.doi.org/10.1063/1.3077013 (3 pages)

Online Publication Date: 4 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors report on an additional effect of the intentionally ordered GaInP layers obtained by using the double tilt GaAs substrates, i.e., the misoriented (001) GaAs substrates toward the two directions of [110] and [−110]. In photoluminescence (PL) spectra at 7 K, it is found that the emission intensity is enhanced with the increase in the substrate misorientation angle toward [−110] direction, along with the redshift of the bandedge. However, the redshift of the bandedge means that the GaInP layers suffer from the ordering of group III atoms. The authors note that the surface morphology in the ordered GaInP layers becomes rapidly rough by the substrate misorientation, even though the linewidths of their PL spectra and x-ray rocking curves are almost similar, irrespective of the misorientation angle. As a result, the light extraction mechanism in the roughened surface structure and the surface roughening mechanism in the intentionally ordered GaInP layers are suggested.
Show PACS
78.66.Fd III-V semiconductors
78.55.Cr III-V semiconductors

Enhanced blue-violet emission by inverse energy transfer to the Ge-related oxygen deficiency centers via Er3+ ions in metal-oxide semiconductor structures

A. Kanjilal, L. Rebohle, M. Voelskow, W. Skorupa, and M. Helm

Appl. Phys. Lett. 94, 051903 (2009); http://dx.doi.org/10.1063/1.3077169 (3 pages) | Cited 11 times

Online Publication Date: 4 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
It is generally believed that the 1.5 μm Er luminescence is enhanced by transferring energy from Si nanocrystals to the nearest Er3+ ions in Er-doped Si-rich SiO2 layers during optical pumping. Here, the influence of Ge nanocrystals instead of excess Si in the same environment is studied using electroluminescence technique on metal-oxide-semiconductor structures. An increase of the 400 nm electroluminescence intensity with a concomitant reduction of the Er-related emission is observed. This is explained in the light of an inverse energy transfer process from Er3+ to the Ge-related oxygen-deficiency centers.
Show PACS
78.60.Fi Electroluminescence
78.67.Bf Nanocrystals, nanoparticles, and nanoclusters

Crystallinity and microstructure in Si films grown by plasma-enhanced chemical vapor deposition: A simple atomic-scale model validated by experiments

P. L. Novikov, A. Le Donne, S. Cereda, Leo Miglio, S. Pizzini, S. Binetti, M. Rondanini, C. Cavallotti, D. Chrastina, T. Moiseev, H. von Känel, G. Isella, and F. Montalenti

Appl. Phys. Lett. 94, 051904 (2009); http://dx.doi.org/10.1063/1.3077187 (3 pages) | Cited 7 times

Online Publication Date: 4 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A joint theoretical and experimental analysis of the crystalline fraction in nanocrystalline films grown by low-energy plasma enhanced chemical vapor deposition is presented. The effect of key growth parameters such as temperature, silane flux, and hydrogen dilution ratio is analyzed and modeled at the atomic scale, introducing an environment-dependent crystallization probability. A very good agreement between experiments and theory is found, despite the use of a single fitting parameter.
Show PACS
68.55.ag Semiconductors
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
52.77.Dq Plasma-based ion implantation and deposition

Size effect of dissipative surface stress on quality factor of microbeams

C. Q. Ru

Appl. Phys. Lett. 94, 051905 (2009); http://dx.doi.org/10.1063/1.3078816 (3 pages) | Cited 10 times

Online Publication Date: 4 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A dissipative surface stress model is suggested to study the surface dissipation of vibrating elastic microbeams. The model is an extension of the well-known Zener model from bulk materials to the surface in the presence of an initial surface tension. Explicit formulas are derived for the frequency-dependent quality factor and the maximum surface dissipation. This model predicts a size-dependent surface dissipation when the size of the cross section downs to nanometers. In particular, the model offers plausible explanation for a few experimental phenomena reported in the most recent literature.
Show PACS
46.40.-f Vibrations and mechanical waves

High-Q micromechanical resonators in a two-dimensional phononic crystal slab

Saeed Mohammadi, Ali Asghar Eftekhar, William D. Hunt, and Ali Adibi

Appl. Phys. Lett. 94, 051906 (2009); http://dx.doi.org/10.1063/1.3078284 (3 pages) | Cited 51 times

Online Publication Date: 5 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
By creating line defects in the structure of a phononic crystal (PC) made by etching a hexagonal array of holes in a 15 μm thick slab of silicon, high-Q PC resonators are fabricated using a complimentary-metal-oxide-semiconductor-compatible process. The complete phononic band gap of the PC structure supports resonant modes with quality factors of more than 6000 at frequencies as high as 126 MHz. The confinement of acoustic energy is achieved by using only a few PC layers confining the cavity region. The calculated frequencies of resonance of the structure using finite element method are in a very good agreement with the experimental data. The performance of these PC resonator structures makes them excellent candidates for wireless communication and sensing applications.
Show PACS
85.85.+j Micro- and nano-electromechanical systems (MEMS/NEMS) and devices
02.70.Dh Finite-element and Galerkin methods

Ab initio tensile experiment on a model of an intergranular glassy film in β-Si3N4 with prismatic surfaces

W. Y. Ching, Paul Rulis, Lizhi Ouyang, and A. Misra

Appl. Phys. Lett. 94, 051907 (2009); http://dx.doi.org/10.1063/1.3079800 (3 pages) | Cited 7 times

Online Publication Date: 5 February 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the results of a large-scale ab initio simulation of an intergranular glassy film (IGF) model in β-Si3N4. It is shown that the stress-strain behavior under uniaxial load in the model with prismatic surfaces and few defective bonds is very different from an earlier IGF model with basal planes. The results are explained by the fundamental electronic structure of the model.
Show PACS
81.40.Jj Elasticity and anelasticity, stress-strain relations
71.23.Cq Amorphous semiconductors, metallic glasses, glasses
81.40.Np Fatigue, corrosion fatigue, embrittlement, cracking, fracture, and failure
62.20.F- Deformation and plasticity
62.20.mm Fracture
Page 1 of 4 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close