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

1 Dec 2003

Volume 83, Issue 22, pp. 4471-4666

Issue Cover Spotlight Figure

Appl. Phys. Lett. 83, 4527 (2003); http://dx.doi.org/10.1063/1.1631051 (3 pages)

Thomas Bligaard, Gisli H. Jóhannesson, Andrei V. Ruban, Hans L. Skriver, Karsten W. Jacobsen, and Jens K. Nørskov
Enlarge Image | Read More
Page 1 of 3 Pages Next Page | Jump to Page
back to top
RSS Feeds

Waveguide tapers and waveguide bends in AlGaAs-based two-dimensional photonic crystals

M. Dinu, R. L. Willett, K. Baldwin, L. N. Pfeiffer, and K. W. West

Appl. Phys. Lett. 83, 4471 (2003); http://dx.doi.org/10.1063/1.1629380 (3 pages) | Cited 13 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In transmission studies of two-dimensional AlGaAs-based photonic crystal waveguide structures, we demonstrate high coupling efficiencies from ridge waveguides to photonic crystal waveguides using photonic crystal waveguide tapers. Enhanced bending efficiencies and bend bandwidths are achieved by use of modified waveguide bends. © 2003 American Institute of Physics.
Show PACS
42.70.Qs Photonic bandgap materials
42.65.Wi Nonlinear waveguides
42.79.Gn Optical waveguides and couplers

Ridge waveguide as a near-field optical source

A. V. Itagi, D. D. Stancil, J. A. Bain, and T. E. Schlesinger

Appl. Phys. Lett. 83, 4474 (2003); http://dx.doi.org/10.1063/1.1631057 (3 pages) | Cited 27 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We investigate the feasibility of using a ridge waveguide at optical frequencies as a near-field optical transducer, using the finite difference time domain method. The complete electromagnetic field picture of the ridge waveguide, in the absence and presence of the irradiated medium, is presented. A power efficiency of 7% and an optical spot with full width half maximum of 50 nm×80 nm is obtained in the medium. We show that impedance considerations play a major role in the transducer-medium optical coupling. © 2003 American Institute of Physics.
Show PACS
42.72.-g Optical sources and standards
42.79.Gn Optical waveguides and couplers
42.82.Et Waveguides, couplers, and arrays
42.81.Qb Fiber waveguides, couplers, and arrays

Measurement of the electro-optic properties of poled polymers at λ = 1.55 μm by means of sandwich structures with zinc oxide transparent electrode

F. Michelotti, A. Belardini, M. C. Larciprete, M. Bertolotti, A. Rousseau, A. Ratsimihety, G. Schoer, and J. Mueller

Appl. Phys. Lett. 83, 4477 (2003); http://dx.doi.org/10.1063/1.1622798 (3 pages) | Cited 20 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on the measurement of the electro-optic properties of poled polymers at λ = 1.55 μm via the Teng and Man technique. Measurements of the electro-optic coefficient obtained for two different sandwich structures, using either indium tin oxide (ITO) or aluminum doped zinc oxide (ZnO:Al) semitransparent electrodes, are compared. The experimental results show that the use of ITO electrodes can lead to a largely wrong evaluation of the electro-optic coefficient r33, with respect to that obtained when using ZnO:Al electrodes, whose plasma resonance is shifted to longer wavelengths. Results on the disperse red 1/methyl-metacrylate based sidechain benchmark system are reported. © 2003 American Institute of Physics.
Show PACS
78.20.Jq Electro-optical effects
42.70.Jk Polymers and organics

Three-dimensional simple cubic woodpile photonic crystals made from chalcogenide glasses

A. Feigel, M. Veinger, B. Sfez, A. Arsh, M. Klebanov, and V. Lyubin

Appl. Phys. Lett. 83, 4480 (2003); http://dx.doi.org/10.1063/1.1631387 (3 pages) | Cited 25 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Construction of three-dimensional photonic crystals for optical wavelengths presents many technological and material science challenges. The submicron-feature-size sculpturing must be performed in high-refractive-index materials. We present the fabrication and optical characterization of ∼ 750 nm feature-size simple cubic woodpile photonic crystals from As2S3 (n ≈ 2.2). The process is based on interference lithography and the layer-by-layer construction. © 2003 American Institute of Physics.
Show PACS
42.70.Qs Photonic bandgap materials
42.70.Ce Glasses, quartz
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)

High extraction efficiency InGaN micro-ring light-emitting diodes

H. W. Choi, M. D. Dawson, P. R. Edwards, and R. W. Martin

Appl. Phys. Lett. 83, 4483 (2003); http://dx.doi.org/10.1063/1.1630352 (3 pages) | Cited 43 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Light-emitting diodes (LEDs) based on an interconnected array of GaN/InGaN micro-ring elements have been demonstrated. The devices have electrical characteristics similar to those of conventional broad-area devices. However, due to the large surface areas provided by the sidewalls, the extraction efficiency is greatly enhanced. Intense light emission at the periphery of the micro-rings is observed upon excitation by an electron beam, suggesting scattering of the photons which are extracted through the sidewalls. The devices provide a doubling in total light output compared to a broad-area reference LED of equal light-generation area. © 2003 American Institute of Physics.
Show PACS
85.60.Jb Light-emitting devices
73.61.Ey III-V semiconductors
78.66.Fd III-V semiconductors

Optical waveguide focusing system with short free-working distance

Haifeng Wang, F. H. Groen, S. F. Pereira, and J. J. M. Braat

Appl. Phys. Lett. 83, 4486 (2003); http://dx.doi.org/10.1063/1.1631063 (2 pages) | Cited 4 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In photonics, light usually diffracts in all directions when it emerges from a planar optical waveguide. Besides this fact, in this letter we show that a waveguide with a rectangular cross section can be turned to a focusing system by using three-dimensional self-imaging technique. We obtained a configuration where the focus of the field lies outside the waveguide, in air, with a spot size of approximately the resolution limit of half a wavelength. This type of waveguide could be used as a coupling element in integrated optics or in high numerical aperture optical systems. © 2003 American Institute of Physics.
Show PACS
42.79.Gn Optical waveguides and couplers
42.82.Et Waveguides, couplers, and arrays

Optical amplification of the cutoff mode in planar asymmetric polymer waveguides

M. Pauchard, M. Vehse, J. Swensen, D. Moses, A. J. Heeger, E. Perzon, and M. R. Andersson

Appl. Phys. Lett. 83, 4488 (2003); http://dx.doi.org/10.1063/1.1627477 (3 pages) | Cited 8 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Modes with low threshold for optical gain were observed at wavelengths close to the cutoff in experiments probing the amplified spontaneous emission of light-emitting polymer thin films. The polymer was the semiconductor layer in a multilayer semiconductor–insulator–metal structure that simulates the one-dimensional waveguide characteristics in the channel of a field-effect transistor. The “cutoff” mode propagates at the polymer/gate-insulator interface, has an optical gain threshold of approximately 10 kW/cm2, and is not influenced by absorption of the gate electrode. The wavelength of the amplified emission tracks the cutoff wavelength of the asymmetric double-waveguide structure and the cutoff mode is, therefore, tunable in wavelength. Our results suggest that the light-emitting field-effect transistor architecture is a promising route for the construction of an injection laser. © 2003 American Institute of Physics.
Show PACS
78.66.Qn Polymers; organic compounds
42.82.Et Waveguides, couplers, and arrays
42.79.Gn Optical waveguides and couplers
42.70.Jk Polymers and organics
78.45.+h Stimulated emission
78.60.Fi Electroluminescence
78.55.Kz Solid organic materials
85.60.Jb Light-emitting devices

Tuning the microcavity resonant wavelength in a two-dimensional photonic crystal by modifying the cavity geometry

G. Subramania, S. Y. Lin, J. R. Wendt, and J. M. Rivera

Appl. Phys. Lett. 83, 4491 (2003); http://dx.doi.org/10.1063/1.1630842 (3 pages) | Cited 4 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
High-quality-factor microcavities in two-dimensional photonic crystals at optical frequencies have a number of technological applications, such as cavity quantum electrodynamics, optical switching, filtering, and wavelength multiplexing. For such applications, it is useful to have a simple approach to tune the microcavity resonant wavelength. In this letter, we propose a microcavity design by which we can tune the resonant wavelength by changing the cavity geometry while still obtaining a high quality factor. © 2003 American Institute of Physics.
Show PACS
42.70.Qs Photonic bandgap materials
42.50.Pq Cavity quantum electrodynamics; micromasers
42.65.Pc Optical bistability, multistability, and switching, including local field effects
42.79.Ci Filters, zone plates, and polarizers
42.79.Sz Optical communication systems, multiplexers, and demultiplexers
42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks

Unusually narrowed emission lines from a single crystal of thiophene/phenylene co-oligomer

Kouki Shimizu, Daichi Hoshino, and Shu Hotta

Appl. Phys. Lett. 83, 4494 (2003); http://dx.doi.org/10.1063/1.1631385 (3 pages) | Cited 16 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have observed unusually narrowed emission lines from a single crystal of thiophene/phenylene co-oligomer. Very narrow lines (0.07 nm of linewidth) arise around 493 and 466 nm by photopumping a long slender region of the crystal. The relevant emissions are due to the lasing caused by high gain media. The photopumping configuration of the crystal in the present studies is useful in examining how the relevant lines are gain narrowed under each specific measurement. © 2003 American Institute of Physics.
Show PACS
78.45.+h Stimulated emission
78.55.Kz Solid organic materials
42.70.Jk Polymers and organics
42.70.Hj Laser materials

Room temperature terahertz phase shifter based on magnetically controlled birefringence in liquid crystals

Chao-Yuan Chen, Tsong-Ru Tsai, Ci-Ling Pan, and Ru-Pin Pan

Appl. Phys. Lett. 83, 4497 (2003); http://dx.doi.org/10.1063/1.1631064 (3 pages) | Cited 25 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present the use of magnetically controlled birefringence in a nematic liquid crystal cell for phase shifting of electromagnetic waves in the range of terahertz frequencies. This device can be operated at room temperature. A maximum phase shift of 141° has been demonstrated at 1.025 THz and the results are in good agreement with theoretical predictions. © 2003 American Institute of Physics.
Show PACS
42.79.Kr Display devices, liquid-crystal devices
85.70.Sq Magnetooptical devices

Focusing light with a single subwavelength aperture flanked by surface corrugations

F. J. García-Vidal, L. Martín-Moreno, H. J. Lezec, and T. W. Ebbesen

Appl. Phys. Lett. 83, 4500 (2003); http://dx.doi.org/10.1063/1.1631384 (3 pages) | Cited 111 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this letter, we show theoretically how a single subwavelength aperture surrounded by a finite array of grooves made on a metallic film can act as a “lens” for electromagnetic radiation within a certain frequency range. The dependence of this resonant focusing ability with the geometrical parameters defining the structure is extensively analyzed. Universal curves for the depth, length and width of the focus as a function of the number of grooves are also given. © 2003 American Institute of Physics.
Show PACS
42.79.Bh Lenses, prisms and mirrors
back to top
RSS Feeds

Sonoplasma generated by a combination of ultrasonic waves and microwave irradiation

Shinfuku Nomura and Hiromichi Toyota

Appl. Phys. Lett. 83, 4503 (2003); http://dx.doi.org/10.1063/1.1631062 (3 pages) | Cited 26 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Plasma chemical vapor deposition (plasma CVD) is a generic term for methods in which a precursor containing a material to be deposited is dissociated in a plasma where it is subject to chemical reactions, and is then deposited as a film on the surface of a heated substrate. A drawback of plasma CVD is that this process cannot be used to synthesize large amounts of adsorbate, or to deposit onto substrates that are vulnerable to high temperatures. As liquids are much denser than gases, synthesis rates are thought to be much higher in the former. The authors have observed the ignition and maintenance of a stable plasma in a liquid hydrocarbon exposed to a combination of ultrasonic waves and microwave radiation. Microwave energy is effectively injected into the interior of acoustic cavitation bubbles, which act as nuclei for the ignition and maintenance of the plasma. Because the plasma is formed in a liquid environment, it is possible to obtain much higher film deposition rates at much lower plasma temperatures than ever before. In addition, this process can be carried out at normal temperatures and pressures. © 2003 American Institute of Physics.
Show PACS
52.50.Dg Plasma sources
43.35.Kp Plasma acoustics
52.77.Dq Plasma-based ion implantation and deposition
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
43.25.Yw Nonlinear acoustics of bubbly liquids
43.35.Ei Acoustic cavitation in liquids
47.55.dp Cavitation and boiling
47.55.D- Drops and bubbles
back to top
RSS Feeds

On the negative value of dielectric permittivity of the water surface layer

N. T. Cherpak, A. A. Barannik, Yu. V. Prokopenko, T. A. Smirnova, and Yu. F. Filipov

Appl. Phys. Lett. 83, 4506 (2003); http://dx.doi.org/10.1063/1.1625792 (3 pages) | Cited 3 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The present letter reports on experimental measurements of a resonant frequency shift of a radially two-layer quasioptical dielectric resonator with whispering gallery wave modes when the internal layer is water or benzine. The sign of the shift indicates that the real part of dielectric permittivity of the water surface layer adjacent to a solid-state dielectric becomes negative (ε′<0). The measurements were carried out at room temperature in microwave K band. © 2003 American Institute of Physics.
Show PACS
77.22.Ch Permittivity (dielectric function)
77.84.Nh Liquids, emulsions, and suspensions; liquid crystals

Temperature-dependent spectral generalized magneto-optical ellipsometry

G. Neuber, R. Rauer, J. Kunze, T. Korn, C. Pels, G. Meier, U. Merkt, J. Bäckström, and M. Rübhausen

Appl. Phys. Lett. 83, 4509 (2003); http://dx.doi.org/10.1063/1.1629145 (3 pages) | Cited 14 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present a setup for temperature-dependent spectral generalized magneto-optical ellipsometry (SGME). This technique gives access to the electronic as well as the magnetic properties of ferromagnetic materials within one single magneto-optical measurement. It also allows the determination of the orientation of the magnetization. We show spectra of the real and the imaginary part of the refractive index N as well as the magneto-optical coupling parameter Q of permalloy and iron films for in-plane magnetization. Our findings demonstrate the relevance of SGME for the understanding of the interplay between electronic and magnetic properties of ferromagnetics. © 2003 American Institute of Physics.
Show PACS
78.20.Ls Magneto-optical effects
07.60.Fs Polarimeters and ellipsometers
75.70.Ak Magnetic properties of monolayers and thin films
75.50.Bb Fe and its alloys
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
78.66.Bz Metals and metallic alloys
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)

Correlation between the volume change during crystallization and the thermal stability of supercooled liquids

T. D. Shen, U. Harms, and R. B. Schwarz

Appl. Phys. Lett. 83, 4512 (2003); http://dx.doi.org/10.1063/1.1631056 (3 pages) | Cited 19 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have measured the density of Pd40Ni40−xCuxP20 (x = 0–40) alloys in the amorphous and crystalline states. For x>30, the alloys are denser in the amorphous than in the crystalline states, which is contrary to the behavior of all known metallic glasses. For Pd40Ni40−xCuxP20 and all other bulk metallic glasses where density data are available in both the amorphous and crystalline states, we find a correlation between the stability of the supercooled liquids and the difference between the molar volumes of the glassy and crystalline phases. The supercooled liquid region is largest for those alloys that show no change in molar volume upon crystallization. © 2003 American Institute of Physics.
Show PACS
61.43.Fs Glasses
64.70.D- Solid-liquid transitions
64.70.P- Glass transitions of specific systems
64.70.Q- Theory and modeling of the glass transition

Interface stability and solid-state amorphization in an immiscible Cu–Ta system

H. R. Gong and B. X. Liu

Appl. Phys. Lett. 83, 4515 (2003); http://dx.doi.org/10.1063/1.1630353 (3 pages) | Cited 10 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Assisted by ab initio calculation, a realistic Cu–Ta potential is derived and applied to determine the energies of Cu/Ta interfaces with various orientations by molecular dynamics simulations. It turns out that the (111) Cu/(100) Ta and (111) Cu/(110) Ta interfaces are thermally stable at a temperature of 873 K and that for the other Cu/Ta interfaces, the interface energies are sufficiently high to drive interfacial reaction and solid-state amorphization, which features an asymmetric behavior, i.e., the amorphous interlayer grows faster toward Cu than that toward Ta. © 2003 American Institute of Physics.
Show PACS
68.35.Fx Diffusion; interface formation
61.43.Dq Amorphous semiconductors, metals, and alloys
68.35.Md Surface thermodynamics, surface energies
61.43.Bn Structural modeling: serial-addition models, computer simulation

Step instability and island formation during annealing of pseudomorphic InGaAs/GaAs layers

A. Riposan, G. K. M. Martin, and J. Mirecki Millunchick

Appl. Phys. Lett. 83, 4518 (2003); http://dx.doi.org/10.1063/1.1631053 (3 pages) | Cited 4 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The morphological stability of compressively strained In0.27Ga0.73As/GaAs pseudomorphic layers has been investigated during annealing. Large three-dimensional islands form at the beginning of annealing on initially flat surfaces, likely to relieve strain energy. The islands disappear with increasing annealing, being reabsorbed into the terraces. At the same time, the step line destabilizes forming cusps that inject two-dimensional vacancy islands into the terrace. At high temperatures, this process leads to a severe deterioration of the morphology that is not due to decomposition. The island dissolution and the development of the step instability are likely alternative paths towards the reduction of surface energy. © 2003 American Institute of Physics.
Show PACS
68.35.B- Structure of clean surfaces (and surface reconstruction)
61.72.Cc Kinetics of defect formation and annealing
68.55.-a Thin film structure and morphology
68.35.Md Surface thermodynamics, surface energies

Room-temperature electroluminescence properties of Er,O-codoped GaAs injection-type light-emitting diodes grown by organometallic vapor phase epitaxy

A. Koizumi, Y. Fujiwara, A. Urakami, K. Inoue, T. Yoshikane, and Y. Takeda

Appl. Phys. Lett. 83, 4521 (2003); http://dx.doi.org/10.1063/1.1630165 (3 pages) | Cited 10 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Room-temperature Er-related electroluminescence (EL) properties have been investigated in Er,O-codoped GaAs (GaAs:Er,O) light-emitting diodes grown by organometallic vapor phase epitaxy. Under forward bias, characteristic emission due to a luminescence center consisting of Er coordinated by O and As was clearly observed at room temperature. The injection current density dependence of the EL intensity and its dynamics revealed extremely large excitation cross section of 1–2×10−15 cm2. The excitation cross section for current injection (σc) is by five orders of magnitude larger than that for optical excitation (σo) in Er-doped fiber amplifiers (10−21–10−20 cm2). © 2003 American Institute of Physics.
Show PACS
78.60.Fi Electroluminescence
85.60.Jb Light-emitting devices

Improvement of InAs quantum-dot optical properties by strain compensation with GaNAs capping layers

X. Q. Zhang, S. Ganapathy, I. Suemune, H. Kumano, K. Uesugi, Yoichi Nabetani, and Takashi Matsumoto

Appl. Phys. Lett. 83, 4524 (2003); http://dx.doi.org/10.1063/1.1629803 (3 pages) | Cited 10 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Two kinds of self-assembled InAs quantum dots (QDs) grown on GaAs (001) substrates were studied. One is capped with GaAs layers and the other with GaNAs strain-compensating layers. Photoluminescence (PL) measurements on the two kinds of InAs QDs showed distinct dependence on the selection of the capping layers. The homogeneity and luminescence efficiency of the InAs QDs were much improved when the net strain was reduced with GaNAs layers. These results demonstrate the importance of net strain compensation for the improved optical quality of InAs QDs. © 2003 American Institute of Physics.
Show PACS
78.67.Hc Quantum dots
78.55.Cr III-V semiconductors
68.65.Hb Quantum dots (patterned in quantum wells)
81.07.Ta Quantum dots
81.16.Dn Self-assembly

Pareto-optimal alloys

Thomas Bligaard, Gisli H. Jóhannesson, Andrei V. Ruban, Hans L. Skriver, Karsten W. Jacobsen, and Jens K. Nørskov

Appl. Phys. Lett. 83, 4527 (2003); http://dx.doi.org/10.1063/1.1631051 (3 pages) | Cited 12 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Large databases that can be used in the search for new materials with specific properties remain an elusive goal in materials science. The problem is complicated by the fact that the optimal material for a given application is usually a compromise between a number of materials properties and the cost. In this letter we present a database consisting of the lattice parameters, bulk moduli, and heats of formation for over 64 000 ordered metallic alloys, which has been established by direct first-principles density-functional-theory calculations. Furthermore, we use a concept from economic theory, the Pareto-optimal set, to determine optimal alloy solutions for the compromise between low compressibility, high stability, and cost. © 2003 American Institute of Physics.
Show PACS
71.15.Mb Density functional theory, local density approximation, gradient and other corrections
02.60.Pn Numerical optimization
82.60.Cx Enthalpies of combustion, reaction, and formation
61.66.Dk Alloys
62.20.D- Elasticity

Heteroepitaxy of GaN on Si(111) realized with a coincident-interface AlN/β-Si3N4(0001) double-buffer structure

Chung-Lin Wu, Jhih-Chun Wang, Meng-Hsuan Chan, Tom T. Chen, and Shangjr Gwo

Appl. Phys. Lett. 83, 4530 (2003); http://dx.doi.org/10.1063/1.1629384 (3 pages) | Cited 24 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present a stacked buffer mechanism for heteroepitaxial growth with large lattice mismatch. The stacked buffer consists of constituent layers, which can form coincident lattices at layer/layer and layer/substrate interfaces. For the case of GaN-on-Si(111) heteroepitaxy, we utilize the 1:2 and 5:2 coincident lattices formed at the β-Si3N4(0001)/Si(111) and AlN(0001)/β-Si3N4(0001) interfaces, respectively, to facilitate the double-buffer layer for GaN-on-Si heteroepitaxial growth. By using this buffer technique, we resolve the issue of autodoping resulting from Si outdiffusion when grown with a single AlN(0001) buffer. As a result, the epitaxial quality of GaN film is also significantly improved. © 2003 American Institute of Physics.
Show PACS
68.55.-a Thin film structure and morphology
68.35.Fx Diffusion; interface formation

Optical properties of gallium oxide films deposited by electron-beam evaporation

M. F. Al-Kuhaili, S. M. A. Durrani, and E. E. Khawaja

Appl. Phys. Lett. 83, 4533 (2003); http://dx.doi.org/10.1063/1.1630845 (3 pages) | Cited 19 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Thin films of gallium oxide were deposited by electron-beam evaporation on unheated substrates. Samples were deposited either without oxygen, or under an oxygen partial pressure of 5×10−4 mbar. The films were amorphous. Films deposited with oxygen were stoichiometric, whereas those deposited without oxygen were substoichiometric. The optical properties of the films were derived from measurements, at normal incidence, of transmittance and reflectance. Films deposited without oxygen had higher values of the refractive index and extinction coefficient. The energy gaps were 5.04 and 4.84 eV for films deposited with and without oxygen, respectively. © 2003 American Institute of Physics.
Show PACS
78.66.Nk Insulators
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
68.55.-a Thin film structure and morphology

Epitaxial growth of quaterphenyl thin films on gold(111)

S. Müllegger, I. Salzmann, R. Resel, and A. Winkler

Appl. Phys. Lett. 83, 4536 (2003); http://dx.doi.org/10.1063/1.1631380 (3 pages) | Cited 16 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The crystal structure and molecular arrangement of para-quaterphenyl (4P) grown on single crystalline Au(111) was investigated over a wide thickness range. The molecular arrangement in the first monolayer, as investigated with low energy electron diffraction, shows a highly regular structure. This wetting layer is defined by adsorbate–substrate interactions and forms a prestage for the epitaxial growth of 4P single crystalline islands, as observed in x-ray diffraction. Two similar orientations of the 4P bulk phase are observed, with the (211) and (311) planes parallel to the Au(111) surface. The alignment of the molecules was kept unchanged from the first monolayers up to a film thickness of 200 nm. © 2003 American Institute of Physics.
Show PACS
68.55.A- Nucleation and growth

Influence of various donors on nonlinear I–V characteristics of tin dioxide ceramics

S. R. Dhage and V. Ravi

Appl. Phys. Lett. 83, 4539 (2003); http://dx.doi.org/10.1063/1.1631390 (3 pages) | Cited 20 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The influence of different donors such as Nb, Ta, Sb, and V on nonlinear current (I)-voltage (V) relations of tin dioxide ceramics is investigated. The room-temperature resistivity (ρ), nonlinear coefficient (α), breakdown electric field (EB) and barrier height (ΦB) are calculated as a function of donor content. The present system contains fewer additives as compared to ZnO varistor wherein small quantities of variety of metal oxides are added. Optimum doping of antimony-doped samples shows promising behavior for low-voltage varistor application. © 2003 American Institute of Physics.
Show PACS
84.32.Ff Conductors, resistors (including thermistors, varistors, and photoresistors)
85.30.Hi Surface barrier, boundary, and point contact devices
73.30.+y Surface double layers, Schottky barriers, and work functions
77.22.Jp Dielectric breakdown and space-charge effects
72.80.Jc Other crystalline inorganic semiconductors
81.05.Je Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides)

Ultraviolet stimulated photocatalytic activity on polycrystalline diamond film surfaces

L. M. Apátiga and V. M. Castaño

Appl. Phys. Lett. 83, 4542 (2003); http://dx.doi.org/10.1063/1.1627470 (2 pages) | Cited 2 times

Online Publication Date: 24 November 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A photocatalytic reaction produced on polycrystalline diamond film surfaces by ultraviolet (UV) light was studied by micro-Raman spectroscopy. The diamond films were specially prepared for this study by the rf-assisted chemical vapor deposition technique. The photocatalytic activity was analyzed in terms of the sharpness of the typical diamond Raman band at 1332 cm−1 and by the weak nondiamond carbon (NDC) features around 1550 cm−1. The micro-Raman spectra show a decrease of the NDC content originally codeposited on diamond film surfaces during the synthesis. This decreasing is proportional to the UV irradiation time, suggesting that the photocatalytic reaction can be controlled by the UV irradiation dose. Since a selective reduction of the NDC phase was achieved on diamond surfaces. The UV irradiation was applied continuously during 1, 2, and 3 days in open atmosphere at room temperature. The role of oxygen radicals, such as ozone (O3) and atomic oxygen (O∗) on the photocatalytic reaction is discussed, as well. © 2003 American Institute of Physics.
Show PACS
82.50.Hp Processes caused by visible and UV light
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces
Page 1 of 3 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close