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

8 Nov 2010

Volume 97, Issue 19, Articles (19xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 97, 193101 (2010); http://dx.doi.org/10.1063/1.3504664 (3 pages)

Qingzhen Hao, Yong Zeng, Xiande Wang, Yanhui Zhao, Bei Wang, I-Kao Chiang, Douglas H. Werner, Vincent Crespi, and Tony Jun Huang
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds

Dangling bond charge transition levels in AlAs, GaAs, and InAs

Hannu-Pekka Komsa and Alfredo Pasquarello

Appl. Phys. Lett. 97, 191901 (2010); http://dx.doi.org/10.1063/1.3515422 (3 pages) | Cited 1 time

Online Publication Date: 8 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Charge transition levels of dangling bonds in III–V semiconductors (AlAs, GaAs, and InAs) are determined via hybrid density-functional calculations. In GaAs, the Ga and As levels are found at 0.28 eV below the conduction band and at 0.16 eV above the valence band, respectively, in good correspondence with measured levels. These defect levels line up across the present semiconductor series for a band alignment based on experimental offsets. For In0.53Ga0.47As, both the In and Ga levels are inferred to resonate with the conduction band while the As level remains in the gap at 0.1 eV from the valence band.
Show PACS
71.55.Eq III-V semiconductors
71.20.Nr Semiconductor compounds
71.15.Mb Density functional theory, local density approximation, gradient and other corrections

Control of surface adatom kinetics for the growth of high-indium content InGaN throughout the miscibility gap

Michael Moseley, Jonathan Lowder, Daniel Billingsley, and W. Alan Doolittle

Appl. Phys. Lett. 97, 191902 (2010); http://dx.doi.org/10.1063/1.3509416 (3 pages) | Cited 4 times

Online Publication Date: 8 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The surface kinetics of InGaN alloys grown via metal-modulated epitaxy (MME) are explored in combination with transient reflection high-energy electron diffraction intensities. A method for monitoring and controlling indium segregation in situ is demonstrated. It is found that indium segregation is more accurately associated with the quantity of excess adsorbed metal, rather than the metal-rich growth regime in general. A modified form of MME is developed in which the excess metal dose is managed via shuttered growth, and high-quality InGaN films throughout the miscibility gap are grown.
Show PACS
68.55.ag Semiconductors
68.43.Mn Adsorption kinetics
68.35.Dv Composition, segregation; defects and impurities
64.75.Bc Solubility
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Coherent controlling plasmon transport properties in metal nanowire coupled to quantum dot

Mu-Tian Cheng, Ya-Qin Luo, Pei-Zhen Wang, and Guang-Xing Zhao

Appl. Phys. Lett. 97, 191903 (2010); http://dx.doi.org/10.1063/1.3514245 (3 pages) | Cited 1 time

Online Publication Date: 8 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We investigate theoretically the transport properties of surface plasmon in a metal nanowire with linear and nonlinear dispersion relations coupled to a quantum dot with three levels in cascaded configuration by full quantum-mechanical approach. The transmission and reflection amplitudes are obtained. The reflection spectrum shows two peaks for the surface plasmon with linear dispersion relation while it can exhibit four peaks when the plasmon has quadratic dispersion relation. The calculations reveal that one can control the plasmon transport properties by adjusting Rabi frequency and circular frequency of a classic optical field.
Show PACS
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)
61.46.Km Structure of nanowires and nanorods (long, free or loosely attached, quantum wires and quantum rods, but not gate-isolated embedded quantum wires)
78.67.Uh Nanowires
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties

In situ synchrotron x-ray characterization of ZnO atomic layer deposition

D. D. Fong, J. A. Eastman, S. K. Kim, T. T. Fister, M. J. Highland, P. M. Baldo, and P. H. Fuoss

Appl. Phys. Lett. 97, 191904 (2010); http://dx.doi.org/10.1063/1.3514254 (3 pages) | Cited 4 times

Online Publication Date: 8 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The utility of in situ synchrotron x-ray scattering and fluorescence in gaining insight into the early stages of the atomic layer deposition process is demonstrated in this study of ZnO growth on Si. ZnO films are found to initially grow as islands, with the onset of coalescence occurring during the fourth growth cycle. The start of coalescence is accompanied by a small increase in surface roughness. After ten cycles of growth, the growth rate decreases from 4.2 to 3.0 Å per cycle, with the growth following expected self-limiting behavior. The overall growth process is consistent with the model of Puurunen and Vandervorts for substrate-inhibited growth [ R. L. Puurunen and W. Vandervorst, J. Appl. Phys. 96, 7686 (2004)] .
Show PACS
68.55.ag Semiconductors
68.49.Uv X-ray standing waves
78.70.Ck X-ray scattering
81.05.Dz II-VI semiconductors
68.35.B- Structure of clean surfaces (and surface reconstruction)

Experimental demonstration of multiwire endoscopes capable of manipulating near-fields with subwavelength resolution

Pavel A. Belov, George K. Palikaras, Yan Zhao, Atiqur Rahman, Constantin R. Simovski, Yang Hao, and Clive Parini

Appl. Phys. Lett. 97, 191905 (2010); http://dx.doi.org/10.1063/1.3516161 (3 pages)

Online Publication Date: 9 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Endoscopes formed by arrays of metallic wires can transmit, magnify, and demagnify near-field distributions with subwavelength resolution. Our experiments demonstrate that despite their small apertures, the parallel multiwire endoscopes can be used to transmit near-field distributions with a resolution of five thousandths of a wavelength to a distance of a half-wavelength in the microwave frequency range, and tapered multiwire endoscopes with flat input and output interfaces provide threefold image magnification and demagnification.
Show PACS
85.60.Gz Photodetectors (including infrared and CCD detectors)
42.79.Pw Imaging detectors and sensors
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors
42.30.Va Image forming and processing
87.85.Pq Biomedical imaging

Controlling metamaterial resonances via dielectric and aspect ratio effects

Sher-Yi Chiam, Ranjan Singh, Weili Zhang, and Andrew A. Bettiol

Appl. Phys. Lett. 97, 191906 (2010); http://dx.doi.org/10.1063/1.3514248 (3 pages) | Cited 3 times

Online Publication Date: 9 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We study ways to enhance the sensitivity and dynamic tuning range of the fundamental inductor-capacitor (LC) resonance in split ring resonators (SRRs) by controlling the aspect ratio of the SRRs and their substrate thickness. We conclude that both factors can significantly affect the LC resonance. We show that metafilms consisting of low height SRRs on a thin substrate are most sensitive to changes in their dielectric environment and thus show excellent potential for sensing applications.
Show PACS
42.82.Gw Other integrated-optical elements and systems
42.70.-a Optical materials
42.79.Wc Optical coatings

Parametric analysis of the strain-dependent behavior of a metamaterial electric resonator

B. Arritt, B. Adomanis, T. Khraishi, and D. Smith

Appl. Phys. Lett. 97, 191907 (2010); http://dx.doi.org/10.1063/1.3507892 (3 pages) | Cited 2 times

Online Publication Date: 10 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this paper, we describe the strain-dependent behavior of an electric-LC (ELC) resonator unit cell, commonly used in metamaterial designs. We leverage analytic expression to understand the way strain manifests itself in a change in electromagnetic (EM) response. We verify the simplified physical models using full-wave simulations and generalize the trends to accommodate the strain profile for any arbitrary plane-stress loading scenario.
Show PACS
84.40.Az Waveguides, transmission lines, striplines
41.20.Jb Electromagnetic wave propagation; radiowave propagation

Structural fingerprints of electronic change in the phase-change-material: Ge2Sb2Te5

B. Cai, D. A. Drabold, and S. R. Elliott

Appl. Phys. Lett. 97, 191908 (2010); http://dx.doi.org/10.1063/1.3516039 (3 pages) | Cited 1 time

Online Publication Date: 10 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this paper, we generate a-Ge2Sb2Te5 models via ab initio molecular dynamic simulations, track the dynamic changes of network at 500 K, and correlate the structural changes in the course of the simulation with changes in electronic structure. Considerable fluctuations of the electronic gap are observed even for a model in equilibrium. We compare our study to experiments and other simulations.
Show PACS
71.20.Lp Intermetallic compounds
05.40.-a Fluctuation phenomena, random processes, noise, and Brownian motion
71.15.-m Methods of electronic structure calculations

Transient phenomena in the dielectric breakdown of HfO2 optical films probed by ultrafast laser pulse pairs

Duy N. Nguyen, Luke A. Emmert, Dinesh Patel, Carmen S. Menoni, and Wolfgang Rudolph

Appl. Phys. Lett. 97, 191909 (2010); http://dx.doi.org/10.1063/1.3511286 (3 pages) | Cited 2 times

Online Publication Date: 10 November 2010

Full Text: Read Online (HTML) | Download PDF


See Also: Publisher's Note

Show Abstract
The laser induced breakdown threshold of HfO2 films is studied with single pairs of pulses of variable delay and 50 fs and 1 ps pulse duration. Two distinct transient regimes are observed that can be related to the relaxation of the electron density from the conduction band via an intermediate state to the valence band. The experimental results are in good agreement with a theoretical model that assumes occupation of mid gap states after the first pulse on a time scale of several tens of picoseconds and subsequent decay of this population via recombination with holes in the valence band on a time scale of several tens of milliseconds.
Show PACS
77.84.Bw Elements, oxides, nitrides, borides, carbides, chalcogenides, etc.
77.55.-g Dielectric thin films
73.61.Ng Insulators
77.22.Jp Dielectric breakdown and space-charge effects
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
71.20.Ps Other inorganic compounds

Electronic properties of nanoscale silver crystals at the interface of silver thick film contacts on n-type silicon

Stefan Kontermann, Gerhard Willeke, and Jan Bauer

Appl. Phys. Lett. 97, 191910 (2010); http://dx.doi.org/10.1063/1.3508950 (3 pages) | Cited 4 times

Online Publication Date: 11 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Silver crystals at the interface of silver thick film contacts play a major role for the current transport across such contacts. As only few crystals are in direct contact with the contact bulk, the specific contact resistance needs to be orders of magnitude smaller compared to the specific contact resistance of the entire contact, if no other current transport mechanism is present. To clarify the current transport mechanism, we present microscopic IV-measurements on a single silver crystal to determine its specific contact resistance to the silicon. We find satisfactory agreement with theoretical values and can explain the macroscopic contact resistance.
Show PACS
73.40.Ns Metal-nonmetal contacts
73.63.Bd Nanocrystalline materials
73.40.Cg Contact resistance, contact potential

Excitation and recombination photodynamics in colloidal cubic SiC nanocrystals

J. Y. Fan, H. X. Li, W. N. Cui, D. J. Dai, and P. K. Chu

Appl. Phys. Lett. 97, 191911 (2010); http://dx.doi.org/10.1063/1.3518062 (3 pages) | Cited 4 times

Online Publication Date: 12 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We studied the photodynamics of the different-sized colloidal cubic SiC nanocrystals in distinct polar and nonpolar solvents. The UV-visible absorption spectral study indicates that the SiC nanocrystals with an average size of 4 nm retain an indirect energy gap; whereas the smaller quantum dots about 1 nm in size exhibit discrete and sharp absorption features indicating their discrete energy levels and the result agrees well with theoretical results. The colloidal SiC nanocrystals exhibit triple-exponential photoluminescence decay with nanosecond-order lifetimes which show slight size-dependence.
Show PACS
78.67.Bf Nanocrystals, nanoparticles, and nanoclusters
78.55.Hx Other solid inorganic materials
78.40.Ha Other nonmetallic inorganics

Fabrication of surface textures by ion implantation for antireflection of silicon crystals

Nirag Kadakia, Sebastian Naczas, Hassaram Bakhru, and Mengbing Huang

Appl. Phys. Lett. 97, 191912 (2010); http://dx.doi.org/10.1063/1.3515842 (3 pages)

Online Publication Date: 12 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on a method based on ion implantation and thermal annealing to fabricate silicon surface textures for antireflection purposes. Modification to crystalline Si surfaces by hydrogen ion implantation is a well known phenomenon, but the surface structures generated by H implantation alone, typically of a low packing density and small aspect ratio, are not effective in suppressing light reflection from Si. We show that coimplantation of hydrogen and argon, combined with thermal annealing and oxidation, can result in an interesting surface morphology in Si crystals, yielding the lowest light reflectance of ∼ 1% over a broad spectral range at various light incident angles. In addition, lattice damage to crystalline Si generated by ion implantation is reduced or completely removed by the annealing processes. Possible mechanisms for the formation of such observed surface textures are discussed.
Show PACS
81.65.Mq Oxidation
61.80.Jh Ion radiation effects
61.72.Cc Kinetics of defect formation and annealing
68.35.bg Semiconductors
61.72.uf Ge and Si

Crystal coherence length effects on the infrared optical response of MgO thin films

J. F. Ihlefeld, J. C. Ginn, D. J. Shelton, V. Matias, M. A. Rodriguez, P. G. Kotula, J. F. Carroll, III, G. D. Boreman, P. G. Clem, and M. B. Sinclair

Appl. Phys. Lett. 97, 191913 (2010); http://dx.doi.org/10.1063/1.3515901 (3 pages)

Online Publication Date: 12 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The role of crystal coherence length on the infrared optical response of MgO thin films was investigated with regard to Reststrahlen band photon-phonon coupling. Preferentially (001)-oriented sputtered and evaporated ion-beam assisted deposited thin films were prepared on silicon and annealed to vary film microstructure. Film crystalline coherence was characterized by x-ray diffraction line broadening and transmission electron microscopy. The infrared dielectric response revealed a strong dependence of dielectric resonance magnitude on crystalline coherence. Shifts to lower transverse optical phonon frequencies were observed with increased crystalline coherence. Increased optical phonon damping is attributed to increasing granularity and intergrain misorientation.
Show PACS
78.66.Nk Insulators
81.15.Cd Deposition by sputtering
78.30.Hv Other nonmetallic inorganics
68.55.-a Thin film structure and morphology
81.15.Jj Ion and electron beam-assisted deposition; ion plating
81.40.Ef Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization

Time evolution of the Ga droplet size distribution during Langmuir evaporation of GaAs(001)

Z. Y. Zhou, W. X. Tang, D. E. Jesson, and J. Tersoff

Appl. Phys. Lett. 97, 191914 (2010); http://dx.doi.org/10.1063/1.3515925 (3 pages)

Online Publication Date: 12 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The time evolution of the Ga droplet size distribution is measured by in situ surface electron microscopy during Langmuir evaporation of GaAs. With a minimum of complexity, we are able to reproduce and explain the major features of the droplet size distribution by a simple Monte Carlo model. Guided by the experiment, the model includes droplet formation in response to coalescence events.
Show PACS
61.20.Ja Computer simulation of liquid structure

Influence of Ga/N ratio on morphology, vacancies, and electrical transport in GaN grown by molecular beam epitaxy at high temperature

G. Koblmüller, F. Reurings, F. Tuomisto, and J. S. Speck

Appl. Phys. Lett. 97, 191915 (2010); http://dx.doi.org/10.1063/1.3514236 (3 pages) | Cited 3 times

Online Publication Date: 12 November 2010

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The effect of Ga/N flux ratio on surface morphology, incorporation of point defects and electrical transport properties of GaN films grown by plasma-assisted molecular beam epitaxy in a recently developed high-temperature growth regime was investigated. The homoepitaxial (0001) GaN films grown at ∼ 780–790 °C showed smoothest morphologies near the cross-over between N-rich and Ga-rich growth (0.75<Ga/N<1.1) contrasting previous observations for low-temperature growth. The higher-quality growth near Ga/N ∼ 1 resulted from lower thermal decomposition rates and was corroborated by slightly lower Ga vacancy concentrations [VGa], lower unintentional oxygen incorporation, and improved electron mobilities. The consistently low [VGa], i.e., ∼ 1016 cm−3 for all films attribute further to the significant benefits of the high-temperature growth regime.
Show PACS
68.55.ag Semiconductors
73.61.Ey III-V semiconductors
81.05.Ea III-V semiconductors
68.35.bg Semiconductors
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
61.72.jd Vacancies
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close