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

18 Oct 2004

Volume 85, Issue 16, pp. 3343-3639

Issue Cover Spotlight Figure

Appl. Phys. Lett. 85, 3570 (2004); http://dx.doi.org/10.1063/1.1807953 (2 pages)

X. N. Zhang, C. R. Li, Z. Zhang, and Z. X. Cao
Enlarge Image | Read More
Page 1 of 5 Pages Next Page | Jump to Page
back to top
RSS Feeds

Efficient Raman amplification in silicon-on-insulator waveguides

T. K. Liang and H. K. Tsang

Appl. Phys. Lett. 85, 3343 (2004); http://dx.doi.org/10.1063/1.1807960 (3 pages) | Cited 42 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We describe a silicon-on-insulator waveguide Raman amplifier which achieves a large fiber-to-fiber optical gain of 6.8 dB using stimulated Raman scattering in a 1.7-cm-long silicon waveguide. By using picosecond pulse pumping at 1557.4 nm wavelength, high net optical gain at the first-order Stokes wavelength of 1694.6 nm was measured. The optical loss from two-photon absorption generated free carriers was reduced by using a low pulse duty cycle and picosecond pulse pumping.
Show PACS
42.55.Wd Fiber lasers
42.55.Px Semiconductor lasers; laser diodes
42.81.Dp Propagation, scattering, and losses; solitons
42.65.Dr Stimulated Raman scattering; CARS
42.65.Es Stimulated Brillouin and Rayleigh scattering
78.30.Am Elemental semiconductors and insulators

High-Q ring resonators in thin silicon-on-insulator

Tom Baehr-Jones, Michael Hochberg, Chris Walker, and Axel Scherer

Appl. Phys. Lett. 85, 3346 (2004); http://dx.doi.org/10.1063/1.1781355 (2 pages) | Cited 20 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have fabricated high-Q microrings from thin silicon-on-insulater SOI layers and measured Q values of 45 000 in these rings, which were then improved to 57 000 by adding a PMMA cladding. The optimal waveguide designs were calculated, and the waveguide losses were analyzed. These high-Q resonators are expected to lead to interesting devices for telecommunication filters and sources as well as optical refractive index sensing.
Show PACS
42.79.Gn Optical waveguides and couplers
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)

Ultrafast-pulse diagnostic using third-order frequency-resolved optical gating in organic films

G. Ramos-Ortiz, M. Cha, S. Thayumanavan, J. Mendez, S. R. Marder, and B. Kippelen

Appl. Phys. Lett. 85, 3348 (2004); http://dx.doi.org/10.1063/1.1807952 (3 pages) | Cited 7 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on the diagnostic of ultrafast pulses by frequency-resolved optical gating (FROG) based on strong third-harmonic generation (THG) in amorphous organic thin films. The high THG conversion efficiency of these films allows for the characterization of sub-nanojoule short pulses emitting at telecommunication wavelengths using a low cost portable fiber spectrometer.
Show PACS
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
42.60.Fc Modulation, tuning, and mode locking
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation

Experimental verification of cross talk reduction in photonic crystal waveguide crossings

Young-Geun Roh, Sungjoon Yoon, Heonsu Jeon, Seung-Ho Han, and Q-Han Park

Appl. Phys. Lett. 85, 3351 (2004); http://dx.doi.org/10.1063/1.1808224 (3 pages) | Cited 8 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have experimentally demonstrated a very low cross talk in photonic crystal waveguide crossings of any kind. For cross talk reduction, we added a resonant cavity to the waveguide intersection designed to operate in microwave frequencies. The two-dimensional waveguide crossing structure was sandwiched between two parallel metal plates to eliminate radiation loss in the vertical direction. Transmission measurements revealed that when designed properly the cross talk reduction was as large as −30 dB at resonance, which is qualitatively consistent with simulation results. From the experimental results, the detailed resonant mode shape at the waveguide intersection was found to play a key role in relaying the input signal in the forward direction and therefore reducing cross talk.
Show PACS
42.79.Gn Optical waveguides and couplers
42.70.Qs Photonic bandgap materials
42.25.Hz Interference

Dual-frequency addressed hybrid-aligned nematic liquid crystal

Yan-Qing Lu, Xiao Liang, Yung-Hsun Wu, Fang Du, and Shin-Tson Wu

Appl. Phys. Lett. 85, 3354 (2004); http://dx.doi.org/10.1063/1.1809282 (3 pages) | Cited 19 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Dual-frequency addressed hybrid-aligned nematic (HAN) liquid crystal cell is demonstrated as a variable optical attenuator at 1.55 μm wavelength. By controlling the low- and high-frequency electric field, the dual-frequency liquid crystal (DFLC) molecules can be reoriented parallel or perpendicular to the substrates so that the maximum obtainable phase modulation is doubled. In comparison to a homogeneous cell, the DFLC HAN cell shows a lower operating voltage and faster response time. Furthermore, the DFLC HAN cell exhibits three stable states that have some applications such as ternary photonic devices.
Show PACS
42.70.Df Liquid crystals
42.79.Kr Display devices, liquid-crystal devices
61.30.Gd Orientational order of liquid crystals; electric and magnetic field effects on order
61.30.Eb Experimental determinations of smectic, nematic, cholesteric, and other structures

Efficient single-layer “twistacene”-doped polymer white light-emitting diodes

Qianfei Xu, Hieu M. Duong, Fred Wudl, and Yang Yang

Appl. Phys. Lett. 85, 3357 (2004); http://dx.doi.org/10.1063/1.1808250 (3 pages) | Cited 70 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Bright, efficient, and stable white polymer light-emitting diodes based on blue polyfluorene doped by a “twistacene,” 6, 8, 15, 17-tetraphenyl-1.18, 4.5, 9.10, 13.14-tetrabenzoheptacene (3) (TBH), are demonstrated. In “twistacene” the terminal pyrene moieties serve two functions: (i) to stabilize the inherently unstable heptacene and (ii) to enable the oligoacene to be a strongly fluorescent molecule. As a result, efficient and very bright white polymer light-emitting diodes are obtained. The maximum luminance of the devices exceeds 20 000 cd∕m2. The maximum luminous efficiency is 3.55 cd∕A at 4228 cd∕m2 while the maximum power efficiency is 1.6 lm∕W at 310 cd∕m2. The device obtains a stable white balance by a combination of energy transfer from the blue polyfluorene to TBH by 1% TBH doping plus the host emission. The device emission color is not a function of bias current, which is ideal for various applications, from lighting to the backlight for liquid crystal displays.
Show PACS
85.60.Jb Light-emitting devices
78.60.Fi Electroluminescence
78.55.Kz Solid organic materials
78.66.Qn Polymers; organic compounds

Ultrabroadband detection of multi-terahertz field transients with GaSe electro-optic sensors: Approaching the near infrared

C. Kübler, R. Huber, S. Tübel, and A. Leitenstorfer

Appl. Phys. Lett. 85, 3360 (2004); http://dx.doi.org/10.1063/1.1808232 (3 pages) | Cited 58 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Field-resolved detection of ultrabroadband infrared pulses is implemented with GaSe crystals. Via phase matching, we extend the detectable frequency range toward the near infrared (λ=2.5 μm) and directly record transform-limited pulses as short as 28 fs with a 3 dB bandwidth of 41 THz. The continuous tunability of the center frequency over a wide interval ranging from 31 THz to the far-infrared is demonstrated using thick sensors.
Show PACS
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors
42.79.Pw Imaging detectors and sensors
85.60.Gz Photodetectors (including infrared and CCD detectors)
42.65.Re Ultrafast processes; optical pulse generation and pulse compression

Optical properties of erbium-implanted porous silicon microcavities

P. J. Reece, M. Gal, H. H. Tan, and C. Jagadish

Appl. Phys. Lett. 85, 3363 (2004); http://dx.doi.org/10.1063/1.1808235 (3 pages) | Cited 10 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have used ion implantation for erbium doping of mesoporous silicon microcavities. Optically active erbium-doped microcavities with Q factors in excess of 1500 have been demonstrated. We observed strong modification of the emission properties of the erbium in the microcavity with an accompanying cavity enhancement factor of 25. In addition, power- and temperature-dependent photoluminescence measurements indicate that erbium-implanted porous silicon has excitation mechanism very similar to that of erbium in a crystalline silicon host.
Show PACS
78.66.Db Elemental semiconductors and insulators
78.55.Ap Elemental semiconductors
78.55.Mb Porous materials
42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.72.uf Ge and Si

Mid-infrared absorption spectroscopy across a 14.4 THz spectral range using a broadband femtosecond optical parametric oscillator

K. A. Tillman, R. R. J. Maier, D. T. Reid, and E. D. McNaghten

Appl. Phys. Lett. 85, 3366 (2004); http://dx.doi.org/10.1063/1.1808239 (3 pages) | Cited 11 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We describe the implementation of optical absorption spectroscopy in which a Ti:sapphire pumped femtosecond optical parametric oscillator based on periodically poled lithium niobate was used as a broadband source to directly acquire a midinfrared absorption spectrum of methane gas. Fourier-transform spectroscopy was performed using the idler output from the optical parametric oscillator to directly acquire spectra spanning over 600 nm (14.4 THz or 480 cm−1) with around 3 nm (78 GHz or 2.6 cm−1) resolution. This approach combines the advantages of spectroscopy using broadband thermal sources with the high power and excellent beam quality of a mode-locked laser source.
Show PACS
07.57.Ty Infrared spectrometers, auxiliary equipment, and techniques
51.70.+f Optical and dielectric properties

High-contrast modulation of light with light by control of surface plasmon polariton wave coupling

A. V. Krasavin, K. F. MacDonald, N. I. Zheludev, and A. V. Zayats

Appl. Phys. Lett. 85, 3369 (2004); http://dx.doi.org/10.1063/1.1808240 (3 pages) | Cited 32 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have demonstrated a mechanism for modulating light with light by controlling the efficiency with which light is coupled into a plasmon polariton wave. An optical fluence of 15 mJ∕cm2 in the control channel is sufficient to achieve nearly a ten-fold intensity modulation of the signal beam reflected from a Glass ∕MgF2∕Ga structure. The mechanism depends on a nanoscale light-induced structural transformation in the gallium layer and has transient switching times of the order of a few tens of nanoseconds. It offers high modulation contrast for signals in the visible and near infrared spectral ranges.
Show PACS
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)
78.68.+m Optical properties of surfaces
64.70.K- Solid-solid transitions
81.30.Hd Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder

Generation and propagation of surface plasmons in periodic metallic structures

G. Torosyan, C. Rau, B. Pradarutti, and R. Beigang

Appl. Phys. Lett. 85, 3372 (2004); http://dx.doi.org/10.1063/1.1806280 (3 pages) | Cited 24 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The generation and propagation of surface plasmon polaritons in periodic metallic structures using femtosecond terahertz pulses is reported. The transmission and emission properties clearly show the influence of Wood’s anomalies. The velocity of propagation is determined experimentally and is in good agreement with a simple model.
Show PACS
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)
71.36.+c Polaritons (including photon-phonon and photon-magnon interactions)

Temperature-dependent photovoltaic effects in the manganite-based heterojunction

J. R. Sun, B. G. Shen, Z. G. Sheng, and Y. P. Sun

Appl. Phys. Lett. 85, 3375 (2004); http://dx.doi.org/10.1063/1.1806560 (3 pages) | Cited 30 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Strong temperature-dependent photovoltaic effects have been observed in the heterojunction composed of a La0.32Pr0.35Ca0.33MnO3 (LPCM) film and a 0.5 wt % Nb-doped SrTiO3 substrate. The photovoltage shows a monotonic increase with the decrease of temperature, and its relative change can be as large as ∼7000% for a modest light intensity of 20 mW (wavelength=632 nm) when cooled from room temperature down to 17 K. The synchronous variation of photovoltage and the magnetization of LPCM indicates the magnetic origin of the temperature dependence of the photovoltaic effect. It is suggested that the temperature affects the photovoltaic effect by modifying the magnetic order, then the band structure of LPCM. An enhancement of the photovoltaic effect under strong light illumination is also observed, which is probably a result of illumination-induced change of the band structure of LPCM.
Show PACS
73.50.Pz Photoconduction and photovoltaic effects
75.70.Cn Magnetic properties of interfaces (multilayers, superlattices, heterostructures)
73.40.Lq Other semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
71.20.Nr Semiconductor compounds

Laser emission from a dye-doped cholesteric liquid crystal pumped by another cholesteric liquid crystal laser

Andro Chanishvili, Guram Chilaya, Gia Petriashvili, Riccardo Barberi, Roberto Bartolino, Gabriella Cipparrone, and Alfredo Mazzulla

Appl. Phys. Lett. 85, 3378 (2004); http://dx.doi.org/10.1063/1.1806561 (3 pages) | Cited 12 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the observation of laser emission from a luminescent dye-doped cholesteric liquid crystal (CLC) excited by another dye-doped CLC laser. The idea is based on the cascade of two CLC cells containing two different dyes where the emission band of the first overlaps the absorption band of the second. This system of low threshold mirrorless lasers emphasizes the main advantages of these organic materials for lasing applications and identifies a simple laser device. Preliminary characterizations of these CLC laser systems produce evidence of remarkable features that suggest fascinating developments. The main aspects are related to the wavelength tunability of the laser emission and to the miniaturization of the device.
Show PACS
42.55.Mv Dye lasers
42.70.Df Liquid crystals
42.79.Kr Display devices, liquid-crystal devices
42.60.Fc Modulation, tuning, and mode locking
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation
78.55.Bq Liquids

Prism coupling to on-chip silicon based bragg cladding waveguide

Yasha Yi, Jessica G. Sandland, Shoji Akiyama, Xiaoman Duan, and Lionel C. Kimerling

Appl. Phys. Lett. 85, 3381 (2004); http://dx.doi.org/10.1063/1.1806562 (3 pages) | Cited 3 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We developed a silicon based asymmetric Bragg cladding waveguide, which is composed of high index contrast Si and Si3N4 clad layers and has omnidirectional reflectivity. Prism coupling was used to demonstrate the guiding mechanism by Bragg reflection. The effective index of the propagation mode was measured directly. The measured effective mode index is less than either the Si or Si3N4 cladding layers, which is a clear demonstration of the Bragg waveguiding principle. Low loss of the Si Bragg cladding waveguide around 0.5 dB∕cm for both TE and TM polarizations is achieved. Potential applications include high power transmission, low dispersion, thin cladding thickness, and nonlinear properties engineering on silicon chip.
Show PACS
42.79.Gn Optical waveguides and couplers
78.30.Hv Other nonmetallic inorganics
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)

Parametric fluorescence based on the third-order susceptibility χ(3) in high nonlinearity fiber

Yi Ni, Qing Wang, Xiaoming Liu, Jiangde Peng, and Bingkun Zhou

Appl. Phys. Lett. 85, 3384 (2004); http://dx.doi.org/10.1063/1.1808506 (3 pages) | Cited 2 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Parametric fluorescence based on the third-order susceptibility χ(3) in high nonlinearity fiber (HNLF) is quantitatively analyzed by the semiclassical method. In an all-fiber setup consisting of 1.45 km HNLF with nonlinear coefficient γ=12 W−1 km−1, parametric fluorescence power of 360 nW and conversion efficiency as high as 6×10−6 W∕W has been measured with pump power of 57 mW. The measured parametric fluorescence spectrum has good symmetry.
Show PACS
42.81.Dp Propagation, scattering, and losses; solitons
42.65.An Optical susceptibility, hyperpolarizability

Efficient ultraviolet electroluminescence from a Gd-implanted silicon metal–oxide–semiconductor device

J. M. Sun, W. Skorupa, T. Dekorsy, M. Helm, L. Rebohle, and T. Gebel

Appl. Phys. Lett. 85, 3387 (2004); http://dx.doi.org/10.1063/1.1808488 (3 pages) | Cited 24 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Strong ultraviolet electroluminescence with an external quantum efficiency above 1% is observed from an indium-tin oxide/SiO2:Gd∕Si metal–oxide–semiconductor structure. The SiO2:Gd active layer is prepared by thermal oxidation followed by Gd+ implantation and annealing. The electroluminescence spectra show a sharp peak at 316 nm from the 6P7∕2 to 8S7∕2 transition of Gd3+ ions. Micrometer-sized electroluminescent devices are demonstrated.
Show PACS
85.60.Jb Light-emitting devices
85.30.Tv Field effect devices
78.60.Fi Electroluminescence
61.72.Cc Kinetics of defect formation and annealing
81.65.Mq Oxidation
78.55.Ap Elemental semiconductors
61.72.up Other materials

Kerr nonlinear effects in AlGaAs multimode waveguides

Marco A. Magaña-Cervantes, Richard M. De La Rue, Daniele Modotto, Costantino De Angelis, Roberto Morandotti, Stefan Linden, Jessica P. Mondia, Henry M. van Driel, and J. Stewart Aitchison

Appl. Phys. Lett. 85, 3390 (2004); http://dx.doi.org/10.1063/1.1807025 (3 pages) | Cited 1 time

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have experimentally investigated the linear and nonlinear characteristics of AlGaAs multimode waveguides. By varying the angle of incidence and∕or the intensity of the input beam, it is possible to change the multipeak intensity distributions at the output facet in a controllable fashion. Numerical simulations have reproduced the main features of the intensity profiles observed at the waveguide output over a range of intensities and angles.
Show PACS
42.79.Gn Optical waveguides and couplers
42.65.Wi Nonlinear waveguides
42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
back to top
RSS Feeds

Electric fields in a sheath near a metal–dielectric interface

E. V. Barnat and G. A. Hebner

Appl. Phys. Lett. 85, 3393 (2004); http://dx.doi.org/10.1063/1.1766075 (3 pages)

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Spatially resolved electric fields in the sheath region near a metal–dielectric junction were measured in a radio-frequency-driven argon plasma. The fields were determined by observing the Stark shifted transitions to the 13d[3∕2]1 Rydberg state by laser-induced fluorescence-dip spectroscopy. Calibration of the Stark shifts for the 13d[3∕2]1 Rydberg state were experimentally obtained in a separate apparatus. Maps of the electric fields illustrate that the structure of the sheath formed around the junction depended on both the surface material and on the configuration of the surface.
Show PACS
52.40.Kh Plasma sheaths
52.70.Kz Optical (ultraviolet, visible, infrared) measurements
52.25.Os Emission, absorption, and scattering of electromagnetic radiation
52.40.Hf Plasma-material interactions; boundary layer effects
32.70.Jz Line shapes, widths, and shifts
32.60.+i Zeeman and Stark effects

Nonmonotonic excitation rates in argon positive column

R. R. Arslanbekov, V. I. Kolobov, E. A. Bogdanov, and A. A. Kudryavtsev

Appl. Phys. Lett. 85, 3396 (2004); http://dx.doi.org/10.1063/1.1806557 (3 pages) | Cited 7 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Nonmonotonic radial distributions of electron excitation rates are obtained in simulations of positive column (PC) in argon for a wide range of gas pressures 5<p<100 Torr, in the tube of radius R=1 cm. This effect cannot be understood from the hydrodynamic point of view and has its origin in the peculiarities of electron kinetics in PC under the studied conditions.
Show PACS
52.25.Fi Transport properties
51.50.+v Electrical properties (ionization, breakdown, electron and ion mobility, etc.)
52.80.-s Electric discharges
52.65.-y Plasma simulation
back to top
RSS Feeds

Thermophotovoltaic generation with selective radiators based on tungsten surface gratings

Hitoshi Sai and Hiroo Yugami

Appl. Phys. Lett. 85, 3399 (2004); http://dx.doi.org/10.1063/1.1807031 (3 pages) | Cited 18 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Two-dimensional surface-relief gratings with a period of 1.0–0.2 μm composed of rectangular microcavities were fabricated on single crystalline W substrates to develop spectrally selective radiators for thermophotovoltaic generation. The radiators displayed strong emission in the near-infrared region where narrow-band-gap photovoltaic cells could convert photons into electricity. The enhancement of thermal emission was attributed to the microcavity effect. Power generation tests were carried out and the W gratings showed more than two times higher generation efficiency, compared to a SiC radiator. The results showed that the microstructured W radiators behave as good selective radiator, with both high efficiency and high power density.
Show PACS
84.60.Jt Photoelectric conversion
85.60.Dw Photodiodes; phototransistors; photoresistors
42.79.Dj Gratings
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
78.66.Fd III-V semiconductors
78.30.Fs III-V and II-VI semiconductors

Oxygen transport and incorporation mechanisms in the dry thermal oxidation of 6H-SiC

C. Radtke, I. J. R. Baumvol, B. C. Ferrera, and F. C. Stedile

Appl. Phys. Lett. 85, 3402 (2004); http://dx.doi.org/10.1063/1.1807033 (3 pages) | Cited 14 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Thermal oxidation of 6H-SiC was investigated by means of isotopic tracing and narrow nuclear resonant reaction profiling techniques. The mechanisms of oxygen transport and incorporation were accessed by sequential oxidations in dry O2 enriched or not in the 18O isotope and subsequent determinations of the 18O profiles. After sequential 16O2∕18O2 or 18O2∕16O2 oxidations of SiC, the 18O profiles were seen to be markedly different from those observed in Si oxidation, which led to the identification of different mechanisms of oxygen incorporation and transport. The gradual nature of the SiO2∕SiC interface was also evidenced by the 18O depth distributions in samples oxidized in a single step in 18O-enriched O2. A probable explanation for this gradual SiO2∕SiC interface is shown to be the formation of C clusters during oxidation.
Show PACS
81.65.Mq Oxidation
82.80.-d Chemical analysis and related physical methods of analysis
68.35.Ct Interface structure and roughness
81.05.Hd Other semiconductors

Second-harmonic generation in transparent surface crystallized glasses in the BaO–B2O3–TeO2 system

G. Senthil Murugan, Takenobu Suzuki, Yasutake Ohishi, Yoshihiro Takahashi, Yasuhiko Benino, Takumi Fujiwara, and Takayuki Komatsu

Appl. Phys. Lett. 85, 3405 (2004); http://dx.doi.org/10.1063/1.1808873 (3 pages) | Cited 8 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A transparent glass–ceramic containing borate crystallites in tellurite glass is reported. Controlled heat treatment resulted in surface crystallization of BaB4O7 in the BaO–B2O3–TeO2 glass system. The second-order optical nonlinearities observed in these surface crystallized glasses were attributed to the distortion present in the BaB4O7 unit cell as evidenced by x-ray powder diffraction studies. A d33 value of 0.08 pm∕V was obtained from the Maker fringe analysis for a surface crystallized glass.
Show PACS
81.05.Pj Glass-based composites, vitroceramics
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
81.40.Gh Other heat and thermomechanical treatments

Effect of nitride passivation on the visible photoluminescence from Si-nanocrystals

Moon-Seung Yang, Kwan-Sik Cho, Ji-Hong Jhe, Se-Young Seo, Jung H. Shin, Kyung Joong Kim, and Dae Won Moon

Appl. Phys. Lett. 85, 3408 (2004); http://dx.doi.org/10.1063/1.1787599 (3 pages) | Cited 27 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The effect of nitride passivation on the visible photoluminescence from nanocrystal Si (nc-Si) is investigated. Silicon-rich silicon nitride (SRSN) and silicon-rich silicon oxide (SRSO), which consist of nc-Si embedded in silicon nitride and silicon oxide, respectively, were prepared by reactive ultrahigh vacuum ion beam sputter deposition followed by a high temperature anneal. Both SRSN and SRSO display photoluminescence peaks after high temperature annealing, coincident with the formation of Si nanocrystals, and similar changes in the peak luminescence position with the excess Si content. However, the luminescence peak positions from SRSN are blueshifted by about 0.6 eV over that of comparable SRSO such that its luminescence peaks in the visible range. The results demonstrate that control of the surface passivation is critical in controlling the nc-Si luminescence, and indicate the possibility of using nitride-passivated nc-Si for visible luminescence applications including white luminescence.
Show PACS
68.55.A- Nucleation and growth
81.65.Rv Passivation
81.40.Gh Other heat and thermomechanical treatments
81.15.Cd Deposition by sputtering
81.15.Jj Ion and electron beam-assisted deposition; ion plating
78.55.Ap Elemental semiconductors
78.66.Db Elemental semiconductors and insulators

Revealing all types of threading dislocations in GaN with improved contrast in a single plan view image

R. Datta, M. J. Kappers, J. S. Barnard, and C. J. Humphreys

Appl. Phys. Lett. 85, 3411 (2004); http://dx.doi.org/10.1063/1.1807962 (3 pages) | Cited 23 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this letter, we demonstrate a transmission electron microscope based technique which reveals all types of threading dislocations (TDs) in GaN with high contrast over a relatively large area, even if the specimen is bent. This method uses a bright-field image with the crystal oriented at the 〈1–21–3〉 zone axis, taken using multi-beam diffraction conditions. Such an image reveals all screw, edge, and mixed types of threading dislocations. The multi-beam imaging technique described here for GaN is more generally applicable to counting the total dislocation density in a wide range of materials and structures.
Show PACS
61.72.Ff Direct observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.)
61.72.Lk Linear defects: dislocations, disclinations
68.55.-a Thin film structure and morphology
68.37.Lp Transmission electron microscopy (TEM)

Surface tension of superheated and undercooled liquid Co–Si alloy

H. P. Wang, W. J. Yao, C. D. Cao, and B. Wei

Appl. Phys. Lett. 85, 3414 (2004); http://dx.doi.org/10.1063/1.1808880 (3 pages) | Cited 6 times

Online Publication Date: 22 October 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The surface tension of superheated and undercooled liquid Co 25 wt.% Si alloy was measured by an electromagnetic oscillating drop method. The experimental temperature regime was from 1384 to 2339 K and a maximum undercooling of 223 K (0.14 TL) was achieved. The surface tension of liquid Co 25 wt.% Si alloy is 1.604 Nm−1 at the liquidus temperature of 1607 K, and its temperature coefficient is −4.0×10−4 Nm−1K−1. On the basis of previous research results of pure Co and Si, an expression is developed to predict the surface tension of binary Co–Si alloy system. The other thermophysical properties, such as the viscosity, the solute diffusion coefficient, and the density of liquid Co 25 wt.% Si alloy are also derived by the relevant theoretical models.
Show PACS
68.03.Cd Surface tension and related phenomena
66.20.-d Viscosity of liquids; diffusive momentum transport
66.10.C- Diffusion and thermal diffusion
Page 1 of 5 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close