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 Feb 2007

Volume 90, Issue 9, Articles (09xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 90, 093127 (2007); http://dx.doi.org/10.1063/1.2710743 (3 pages)

Y. Q. Li, J. X. Tang, H. Wang, J. A. Zapien, Y. Y. Shan, and S. T. Lee
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds

Cubic InN growth on sapphire (0001) using cubic indium oxide as buffer layer

J. G. Lozano, F. M. Morales, R. García, D. González, V. Lebedev, Ch. Y. Wang, V. Cimalla, and O. Ambacher

Appl. Phys. Lett. 90, 091901 (2007); http://dx.doi.org/10.1063/1.2696282 (3 pages) | Cited 21 times

Online Publication Date: 26 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Cubic InN layers were grown by molecular beam epitaxy on buffer layers of indium oxide prepared onto sapphire (0001) substrates. The structure was analyzed by means of electron diffraction and transmission electron microscopy. The intermediate indium oxide layer presents a body centered cubic (bcc) structure, with bcc-In2O3(001)‖Al2O3(0001) plane relationship. Thereupon, a zinc-blende phase of InN (001) was grown with a reticular misfit of 1.6% and a significant reduction of mismatch-related defects. This good coherence offers a promising expectation to obtain high quality cubic InN layers superior to other highly mismatched cubic substrates used previously.
Show PACS
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.55.A- Nucleation and growth
68.55.-a Thin film structure and morphology
68.37.Lp Transmission electron microscopy (TEM)

Critical film thickness dependence on As flux in In0.27Ga0.73As/GaAs(001) films

A. Riposan, J. Mirecki Millunchick, and Chris Pearson

Appl. Phys. Lett. 90, 091902 (2007); http://dx.doi.org/10.1063/1.2476259 (3 pages) | Cited 5 times

Online Publication Date: 26 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The transition between planar and nonplanar growth is examined for compressively strained In0.27Ga0.73As/GaAs(001) films using reflection high energy electron diffraction, atomic force microscopy, and scanning tunneling microscopy (STM). For a narrow range of temperature and composition, the critical thickness (tSK) is strongly dependent on As flux. For high values of As flux, tSK increases by more than a factor of 2. The morphology of three-dimensional islands formed during the initial stages of nonplanar growth is also characterized by high resolution STM.
Show PACS
81.05.Ea III-V semiconductors
68.55.-a Thin film structure and morphology
68.55.A- Nucleation and growth
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Third order nonlinear susceptibility of InN at near band-gap wavelengths

F. B. Naranjo, M. González-Herráez, H. Fernández, J. Solis, and E. Monroy

Appl. Phys. Lett. 90, 091903 (2007); http://dx.doi.org/10.1063/1.2709891 (3 pages) | Cited 4 times

Online Publication Date: 26 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors report room-temperature measurements of the third order nonlinear susceptibility modulus ∣χ(3)∣ of thick ( ∼ 600 nm) InN layers. Transmission measurements provide a room-temperature value for the optical band gap of the samples slightly above 1500 nm. Third order nonlinear optical susceptibility has been measured using degenerate four wave mixing experiments at wavelengths near and above band gap. ∣χ(3)∣ values of (4.2–10)×10−10 esu were measured at this wavelength range. The associated relaxation time of the generated population grating at 1500 nm was measured. The obtained value of 4.8 ps is consistent with a nonradiative recombination mechanism.
Show PACS
42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials
42.65.An Optical susceptibility, hyperpolarizability
42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
42.79.Dj Gratings

Phase change behaviors of Sn-doped Ge–Sb–Te material

W. D. Song, L. P. Shi, X. S. Miao, and T. C. Chong

Appl. Phys. Lett. 90, 091904 (2007); http://dx.doi.org/10.1063/1.2475390 (3 pages) | Cited 19 times

Online Publication Date: 27 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Sn-doped Ge–Sb–Te material was prepared by laser synthesis. It has a rocksalt crystal structure for Sn doping content less than 30 at. %. A phase change temperature tester was developed to in situ measure crystallization temperature and melting point of Sn-doped Ge–Sb–Te. The crystalliza-tion temperature of Sn-doped Ge–Sb–Te is close to that of Ge2Sb2Te5 while its melting point is much lower than that of Ge2Sb2Te5. The melting points of Sn9.8Ge20.3Sb28.4Te41.5 and Sn18.8Ge19.5Sb25.3Te36.4 are 475 and 450 °C, respectively. The crystallization speed was tested by an ultraviolet light at pulse duration of 30 ns. It exhibits a high crystallization speed.
Show PACS
64.70.D- Solid-liquid transitions
64.70.K- Solid-solid transitions
42.62.-b Laser applications
61.66.Fn Inorganic compounds

SiOx/Si radial superlattices and microtube optical ring resonators

R. Songmuang, A. Rastelli, S. Mendach, and O. G. Schmidt

Appl. Phys. Lett. 90, 091905 (2007); http://dx.doi.org/10.1063/1.2472546 (3 pages) | Cited 37 times

Online Publication Date: 27 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Scanning and transmission electron microscopy reveals that SiOx/Si layers can roll up into microtubes and radial superlattices on a Si substrate. These hybrid objects are thermally stable up to 850 °C and emit light in the visible spectral range at room temperature. For tubes disengaged from the substrate surface, optically resonant emissions with mode spacings inversely proportional to the tube diameter are observed and agree excellently with those obtained from finite-difference time-domain simulations. The resonant modes recorded are strictly polarized along the tube axis.
Show PACS
42.79.Wc Optical coatings
42.79.-e Optical elements, devices, and systems

Highly intense violet-blue light emission at room temperature in structurally disordered SrZrO3 powders

V. M. Longo, L. S. Cavalcante, A. T. de Figueiredo, L. P. S. Santos, E. Longo, J. A. Varela, J. R. Sambrano, C. A. Paskocimas, F. S. De Vicente, and A. C. Hernandes

Appl. Phys. Lett. 90, 091906 (2007); http://dx.doi.org/10.1063/1.2709992 (3 pages) | Cited 28 times

Online Publication Date: 27 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Violet-blue photoluminescence was produced at room temperature in a structurally disordered SrZrO3 perovskite structure with a 350.7 nm excitation line. The intensity of this emission was higher than that of any other perovskites previously studied. The authors discuss the role of structural order-disorder that favors the self-trapping of electrons and charge transference, as well as a model to elucidate the mechanism that triggers photoluminescence. In this model the wide band model, the most important events occur before excitation.
Show PACS
78.55.Hx Other solid inorganic materials
64.70.K- Solid-solid transitions

Photoreflectance and reflectance investigation of deuterium-irradiated GaAsN

M. Geddo, T. Ciabattoni, G. Guizzetti, M. Galli, M. Patrini, A. Polimeni, R. Trotta, M. Capizzi, G. Bais, M. Piccin, S. Rubini, F. Martelli, and A. Franciosi

Appl. Phys. Lett. 90, 091907 (2007); http://dx.doi.org/10.1063/1.2709629 (3 pages) | Cited 9 times

Online Publication Date: 27 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The effect of deuterium irradiation on the optical and strain properties of GaAsN/GaAs heterostructures was investigated by photoreflectance and reflectance techniques. The strain occurring in as-grown and deuterated GaAsN layers is monitored and measured by means of photoreflectance spectroscopy, highlighting the strain inversion after irradiation. By combining static and modulated reflectance results, evidence is given that the deuterium-induced recovery of the GaAs band gap as well as the strain inversion in GaAsN layers are accompanied by a 0.4%–0.8% reduction of the refractive index in the 1.31 and 1.55 μm spectral windows of interest for fiber optic communications. These results anticipate a single step process to an in-plane confinement of carriers and photons.
Show PACS
78.66.Fd III-V semiconductors
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
61.80.Jh Ion radiation effects
68.35.Gy Mechanical properties; surface strains

Multiscale model for atomic force microscope array mechanical behavior

M. Lenczner

Appl. Phys. Lett. 90, 091908 (2007); http://dx.doi.org/10.1063/1.2710001 (3 pages) | Cited 4 times

Online Publication Date: 27 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The author presents a first simplified two-scale model of the elastic structure of an atomic force microscope array. It can be used for rapid prototyping and for designing model based control loops. Its derivation is based on the concept of two-scale approximation.
Show PACS
07.79.Lh Atomic force microscopes

Highly efficient oxidation of silicon at low temperatures using atmospheric pressure plasma

Hiroaki Kakiuchi, Hiromasa Ohmi, Makoto Harada, Heiji Watanabe, and Kiyoshi Yasutake

Appl. Phys. Lett. 90, 091909 (2007); http://dx.doi.org/10.1063/1.2710190 (3 pages) | Cited 9 times

Online Publication Date: 28 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Silicon oxide (SiO2) layers were formed with initial oxidation rates in the range of 6.2–14.1 nm/min in the temperature range of 150–400 °C by oxidizing Si(001) wafers. Such a high-rate and low-temperature oxidation was realized by using a stable glow He/O2 plasma excited at atmospheric pressure by a 150 MHz very high-frequency power. Increasing the temperature led to both the higher oxidation rate and the better quality of SiO2 and SiO2/Si interface. The oxidation at 400 °C showed an interface trap density of 6.2×1010 eV−1 cm−2, which is considerably lower than that in a radical oxidation process using low-pressure He/O2 plasma at the same temperature.
Show PACS
81.05.Cy Elemental semiconductors
81.65.Mq Oxidation
52.77.-j Plasma applications
73.20.At Surface states, band structure, electron density of states

Properties of epitaxial GaN on refractory metal substrates

Jaime A. Freitas, Jr., Larry B. Rowland, Jihyun Kim, and Mohammad Fatemi

Appl. Phys. Lett. 90, 091910 (2007); http://dx.doi.org/10.1063/1.2709512 (3 pages) | Cited 1 time

Online Publication Date: 28 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors demonstrate here that GaN films with good surface morphology and structural, optical, and electronic properties can be grown on metallic titanium carbide substrates. X-ray rocking curve and Raman scattering measurements confirmed the high crystalline quality of the wurtzite structure film. Variable temperature photoluminescence measurements of sharp and intense emission lines provided insights into the nature of the recombination processes, the carrier background type, and the carrier concentration. The high quality of the interface and substrate Ohmic contacts was verified. The ability to grow high-quality films on metallic substrates provides the means for advanced vertical and high-power and/or high-temperature device fabrication.
Show PACS
81.05.Ea III-V semiconductors
68.55.A- Nucleation and growth
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
73.61.Ey III-V semiconductors
78.66.Fd III-V semiconductors
78.55.Et II-VI semiconductors

Pseudogap formation in MnPt and MnPd alloys

Masato Kubota, Kanta Ono, Rie Y. Umetsu, Hiroyuki Akinaga, Akimasa Sakuma, and Kazuaki Fukamichi

Appl. Phys. Lett. 90, 091911 (2007); http://dx.doi.org/10.1063/1.2561008 (3 pages) | Cited 1 time

Online Publication Date: 28 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors performed an optical spectroscopy to observe the electronic structure of L10-type ordered Mn-based alloys. The effect of disorder on pseudogap formation in Mn1−xPtx (x = 0.47, 0.50, 0.51, and 0.54) and Mn1−xPdx (x = 0.502, 0.515, and 0.535) alloys has been clarified. The optical reflectivity shows a clear dip around 0.5 eV for both MnPt and MnPd alloys, which corresponds to the pseudogap formation. On the other hand, the pseudogap is rather unclear in the other nonequiatomic compositions. This indicates that the pseudogap formation is deeply related to the degree of the ordering in the Mn-based alloys.
Show PACS
71.20.Be Transition metals and alloys
78.20.-e Optical properties of bulk materials and thin films

Resonant crystal band gap metamaterials in the microwave regime and their exotic amplification of evanescent waves

Ruopeng Liu, Tie Jun Cui, Bo Zhao, Xian Qi Lin, Hui Feng Ma, Da Huang, and David R. Smith

Appl. Phys. Lett. 90, 091912 (2007); http://dx.doi.org/10.1063/1.2709897 (3 pages) | Cited 4 times

Online Publication Date: 28 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors realize resonant crystal band gap metamaterials (CBMs) using circuit structures in the microwave regime, which behave quite differently from the conventional photonic band gap structures. They show that a periodic array of series inductor and shunt capacitor is equivalent to a CBM similar to a magnetic plasma at higher frequency band, and a periodic array of series capacitor and shunt inductor behaves like a CBM similar to an electric plasma at lower frequency band. The equivalent medium parameters have been derived in both cases, which show the existence of conjugate loss in imaginary parts. When two such structures are cascaded together, the authors demonstrate that evanescent waves are amplified and transmitted in a very narrow frequency band under the antimatching condition. Such a feature can be used to design extremely narrow band filters. Theoretical predictions, circuit simulations, and experimental results are presented to validate their conclusions.
Show PACS
42.70.Qs Photonic bandgap materials
84.40.Dc Microwave circuits

Surface micromachined freestanding ZnO microbridge and cantilever structures on Si(111) substrates

S. Vicknesh, S. Tripathy, Vivian K. X. Lin, S. J. Chua, Bhupendra Kumar, and Hao Gong

Appl. Phys. Lett. 90, 091913 (2007); http://dx.doi.org/10.1063/1.2642619 (3 pages) | Cited 7 times

Online Publication Date: 28 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this study, the authors report on the fabrication processes to realize the freestanding ZnO micromechanical structures on Si(111) substrates. Arrays of freestanding cantilevers and microbridges have been fabricated using a combination of dry etching techniques. The mechanical properties of the released ZnO structures are characterized by micro-Raman spectroscopy. The residual stress in these freestanding micromechanical structures is determined from the E2(2) phonon peak shift. Such a method to realize the freestanding structures on Si platform would be useful for the fabrication of ZnO-based microelectromechanical systems and sensors.
Show PACS
85.85.+j Micro- and nano-electromechanical systems (MEMS/NEMS) and devices
81.20.Wk Machining, milling
81.65.Cf Surface cleaning, etching, patterning

Thermodynamics of the B–Ca, B–Sr, and B–Ba systems: Applications for the fabrications of CaB6, SrB6, and BaB6 thin films

Shunli Shang and Zi-Kui Liu

Appl. Phys. Lett. 90, 091914 (2007); http://dx.doi.org/10.1063/1.2710081 (3 pages) | Cited 4 times

Online Publication Date: 28 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Using the thermodynamic descriptions previously modeled in the boron-alkaline earth metal systems, B–Ca, B–Sr, and B–Ba, the pressure-temperature phase diagrams of these systems have been obtained in the present work, which provide insights into appropriate processing conditions for depositions of the divalent alkaline-earth metal hexaborides, CaB6, SrB6, and BaB6. The present work indicates that the lower the growth pressures, the wider the growth temperature ranges and, in turn, the more favorite control of the growth of thin films for the ferromagnetic hexaborides.
Show PACS
68.55.A- Nucleation and growth
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.30.Dz Phase diagrams of other materials
75.70.Ak Magnetic properties of monolayers and thin films
75.50.Dd Nonmetallic ferromagnetic materials

Substrate pit formation and surface wetting during thermal annealing of strained-Si/relaxed-Si0.78Ge0.22 heterostructure

C. H. Jang, S. I. Paik, Y. W. Kim, and N.-E. Lee

Appl. Phys. Lett. 90, 091915 (2007); http://dx.doi.org/10.1063/1.2696228 (3 pages) | Cited 3 times

Online Publication Date: 28 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
During the elevated-temperature thermal annealing of a strained-Si/relaxed-Si0.78Ge0.22 heterostructure, deep substrate pits penetrating into the relaxed-Si0.78Ge0.22 buffer were formed and the strained-Si surface was wetted by the Si and Ge atoms originating from the deep pits. The pit formation and surface wetting are presumably due to the decrease in the strained-Si surface energy, resulting in a reduction in the total energy. The strain of the remaining strained-Si layer situated away from the deep pits was slightly increased despite the increased relaxation of the SiGe buffer, which implies that the remaining strained-Si layer was morphologically stabilized by the SiGe wetting.
Show PACS
61.72.Cc Kinetics of defect formation and annealing
68.08.Bc Wetting
68.55.-a Thin film structure and morphology
68.35.Md Surface thermodynamics, surface energies
81.40.Jj Elasticity and anelasticity, stress-strain relations
62.40.+i Anelasticity, internal friction, stress relaxation, and mechanical resonances

Enhanced photoluminescence of Nd2O3 nanoparticles modified with silane-coupling agent: Fluorescent resonance energy transfer analysis

Kehan Yu, Xiaoming Qiu, Xiangxing Xu, Wei Wei, Bo Peng, and Zhiwei Zhou

Appl. Phys. Lett. 90, 091916 (2007); http://dx.doi.org/10.1063/1.2710479 (3 pages) | Cited 4 times

Online Publication Date: 28 February 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A liquid laser medium with a lifetime of 492 μs and a fluorescent quantum efficiency of 52.5% has been presented by stably dispersing dimethyl dichorosilane-modified Nd2O3 nanoparticles in dimethylsulfoxide. Its optical properties and mechanism were investigated and explained by fluorescence resonance energy transfer theory. The calculation result shows that the quenching of NdIII 4F3/2→4I11/2 transition via O–H vibrational excitation can be eventually neglected. The main reason is that the silane-coupling agent molecules remove the –OH groups on Nd2O3 nanoparticles and form a protective out layer.
Show PACS
78.67.Bf Nanocrystals, nanoparticles, and nanoclusters
78.55.Hx Other solid inorganic materials

Flow instability of fluid-metal layer generated by laser pulse on an inclined metal surface: Experiments and simulation

Stjepan Lugomer, Aleksandar Maksimović, Gabor Peto, and Albert Karacs

Appl. Phys. Lett. 90, 091917 (2007); http://dx.doi.org/10.1063/1.2710749 (3 pages) | Cited 3 times

Online Publication Date: 1 March 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors have shown that nanosecond laser-matter interaction with metal surface under an angle causes the formation of nonlinear micron-scale waves and localized structures resembling the gravitationally caused flow structures on the inclined plate. Juxtaposition of experimentally generated and numerically simulated structures on the basis of the equation derived by Frenkel and Indireshkumar [Phys. Rev. E 55, 1174 (1997)] shows a very good qualitative agreement; the experiments confirmed the dependence of the structure evolution on the laser power profile and on the irradiation angle. Dispersion of ordered long-range structures into chaotic ones was observed for the irradiation angle of θ = 20°.
Show PACS
47.20.Ma Interfacial instabilities (e.g., Rayleigh-Taylor)
47.11.-j Computational methods in fluid dynamics
47.35.Bb Gravity waves
47.52.+j Chaos in fluid dynamics
79.20.Ds Laser-beam impact phenomena

Mapping local strain in thin film/substrate systems using x-ray microdiffraction topography

Hanfei Yan, Conal E. Murray, and I. C. Noyan

Appl. Phys. Lett. 90, 091918 (2007); http://dx.doi.org/10.1063/1.2711189 (3 pages) | Cited 8 times

Online Publication Date: 2 March 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors report experimental data and modeling results for reflection microbeam x-ray topographs from a Si substrate strained by an overlying pseudomorphic SiGe film edge. The diffracted x-ray intensity from the Si substrate is strongly asymmetric as a function of distance from the film edge. A model of the diffracted intensity based on the classical Ewald–von Laue dynamical diffraction theory for an antisymmetric strain distribution indicates that the asymmetry in the diffracted beam profile is only due to the scattering process; individual intensity maxima in the intensity profile cannot be uniquely ascribed to individual features in the local strain distribution.
Show PACS
68.60.Bs Mechanical and acoustical properties

Particle tracking velocimetry using fast x-ray phase-contrast imaging

Kyoung-Su Im, K. Fezzaa, Y. J. Wang, X. Liu, Jin Wang, and M.-C. Lai

Appl. Phys. Lett. 90, 091919 (2007); http://dx.doi.org/10.1063/1.2711372 (3 pages) | Cited 13 times

Online Publication Date: 2 March 2007

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors demonstrate the use of millisecond x-ray phase-contrast imaging for velocity measurement of particle-laden flows in an optically opaque vessel. Taking advantage of particle size polydispersity, this single-particle tracking approach is extremely effective on flows with tracer particles exhibiting a great size distribution ranging from 1 μm to hundreds of micrometers, which is impossible for visible-light-based techniques. Furthermore, a tomographic reconstruction was applied to yield the three-dimensional flow velocity field and its particle size dependence with unprecedented sensitivity.
Show PACS
47.80.Jk Flow visualization and imaging
47.80.Cb Velocity measurements
47.55.Kf Particle-laden flows
47.60.-i Flow phenomena in quasi-one-dimensional systems
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close