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

27 Nov 2006

Volume 89, Issue 22, Articles (22xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 89, 223115 (2006); http://dx.doi.org/10.1063/1.2397384 (3 pages)

D. L. Fan, F. Q. Zhu, R. C. Cammarata, and C. L. Chien
Enlarge Image | Read More
Page 1 of 7 Pages Next Page | Jump to Page
back to top
RSS Feeds

Silicon-based photonic crystal nanocavity light emitters

Maria Makarova, Jelena Vuckovic, Hiroyuki Sanda, and Yoshio Nishi

Appl. Phys. Lett. 89, 221101 (2006); http://dx.doi.org/10.1063/1.2396903 (3 pages) | Cited 22 times

Online Publication Date: 27 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors have demonstrated an up to sevenfold enhancement of photoluminescence from silicon-rich silicon nitride film due to a single photonic crystal cavity. The enhancement is partially attributed to the Purcell effect [Purcell, Phys. Rev. 69, 681 (1946)], which is predicted to be up to 35-fold by finite difference time-domain calculations for emitters spectrally and spatially aligned with the electric field. Experimentally measured cavity quality factors vary in the range of 200–300, showing excellent agreement with calculations. The emission peak can be tuned to any wavelength in the 600–800 nm range.
Show PACS
42.70.Qs Photonic bandgap materials
78.55.Hx Other solid inorganic materials
78.66.Nk Insulators
42.79.Wc Optical coatings

Temporal-coherence gain of superlens image with quasimonochromatic source

Xunya Jiang, Wenda Han, Peijun Yao, and Wei Li

Appl. Phys. Lett. 89, 221102 (2006); http://dx.doi.org/10.1063/1.2390627 (3 pages) | Cited 3 times

Online Publication Date: 27 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
From numerical experiments, a dramatic observation of temporal-coherence gain of the image field is made for the negative-index superlens with a random quasimonochromatic source, even when there is almost no reflection and no frequency filtering effects. A single-parameter theory which can explain the phenomenon quantitatively is constructed based on the physical picture that signals propagating through the negative-index material on different paths have a different retardation time. The theoretical results agree excellently with the numerical ones.
Show PACS
42.70.-a Optical materials
42.79.Bh Lenses, prisms and mirrors

Increasing the electrical conductivity of poly(vinylidene fluoride) by KrF excimer laser irradiation

Yaling Ji and Yijian Jiang

Appl. Phys. Lett. 89, 221103 (2006); http://dx.doi.org/10.1063/1.2390632 (3 pages) | Cited 4 times

Online Publication Date: 27 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This letter describes the increase in electrical conductivity of poly(vinylidene fluoride) induced by excimer laser irradiation with λ = 248 nm. The electrical conductivity was found to increase from 10−13 to 10−4 Ω−1 cm−1. As a result, experiments produced a transition in the property of the material from an insulator to a conductor. Optimal conditions for laser irradiation were determined in terms of the laser energy density, the repetition frequency, and the total number of laser shots. This letter also discusses the micromechanics of increasing conductivity in the light of Raman spectroscopy and x-ray photoelectron spectroscopy.
Show PACS
72.60.+g Mixed conductivity and conductivity transitions
72.80.Le Polymers; organic compounds (including organic semiconductors)
71.30.+h Metal-insulator transitions and other electronic transitions
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
77.65.-j Piezoelectricity and electromechanical effects
77.84.Jd Polymers; organic compounds

Achievement of ultrahigh quality factors in GaAs photonic crystal membrane nanocavity

Evelin Weidner, Sylvain Combrié, Nguyen-Vi-Quynh Tran, Alfredo De Rossi, Julien Nagle, Simone Cassette, Anne Talneau, and Henri Benisty

Appl. Phys. Lett. 89, 221104 (2006); http://dx.doi.org/10.1063/1.2390648 (3 pages) | Cited 38 times

Online Publication Date: 27 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors realized an ultrahigh quality factor nanocavity in a GaAs membrane with the highest loaded Q reported to date of 250 000 in a side-coupled cavity-waveguide system. This result could be obtained using an original aluminum-free material system combined with a carefully adjusted fabrication technology, yielding a device with small roughness and very good verticality of holes as well as small disorder. The authors show that the intrinsic Q factor is around 3.0×105 using a coupled-mode model.
Show PACS
42.82.Et Waveguides, couplers, and arrays
42.70.Qs Photonic bandgap materials
42.79.Gn Optical waveguides and couplers

Spectroscopy of GaAs/AlGaAs quantum-cascade lasers using hydrostatic pressure

S. R. Jin, C. N. Ahmad, S. J. Sweeney, A. R. Adams, B. N. Murdin, H. Page, X. Marcadet, C. Sirtori, and S. Tomić

Appl. Phys. Lett. 89, 221105 (2006); http://dx.doi.org/10.1063/1.2364159 (3 pages) | Cited 5 times

Online Publication Date: 27 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors have measured the output spectrum and the threshold current in 9.2 μm wavelength GaAs/Al0.45Ga0.55As quantum-cascade lasers at 115 K as a function of hydrostatic pressure up to 7.3 kbars. By extrapolation back to ambient pressure, thermally activated escape of electrons from the upper lasing state up to delocalized states of the Γ valley is shown to be an important contribution to the threshold current. On the other hand leakage into the X valley, although it has a very high density of states and is nearly degenerate with the Γ band edge in the barrier, is insignificant at ambient pressure.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.By Design of specific laser systems

Time resolved photoluminescence spectroscopy of surface-plasmon-enhanced light emission from conjugate polymers

Terrell D. Neal, Koichi Okamoto, Axel Scherer, Michelle S. Liu, and Alex K.-Y. Jen

Appl. Phys. Lett. 89, 221106 (2006); http://dx.doi.org/10.1063/1.2397481 (3 pages) | Cited 13 times

Online Publication Date: 28 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors have experimentally verified that the light emission from conjugated polymers can be enhanced through the use of surface plasmon coupling layers. Carrier dynamics of such plasmon-enhanced organic light emitters were studied and a recombination rate increase due to surface plasmon polaritons was experimentally observed. Internal quantum efficiency data from the polyfluorenes studied follow the trend supported by the time resolved photoluminescence measurements.
Show PACS
78.55.Kz Solid organic materials
78.47.-p Spectroscopy of solid state dynamics
78.68.+m Optical properties of surfaces
42.70.Jk Polymers and organics
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
71.36.+c Polaritons (including photon-phonon and photon-magnon interactions)

Synthesis and thermoelectric properties of KyCo4Sb12

Y. Z. Pei, L. D. Chen, W. Zhang, X. Shi, S. Q. Bai, X. Y. Zhao, Z. G. Mei, and X. Y. Li

Appl. Phys. Lett. 89, 221107 (2006); http://dx.doi.org/10.1063/1.2397538 (3 pages) | Cited 49 times

Online Publication Date: 28 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Polycrystalline K-filled CoSb3 are synthesized successfully. The uplimit for K filling is at least 0.45, being higher than those of either alkaline-earth (AE) or rare-earth (RE) metals but being in consistent with our earlier theoretical prediction. The measured transport properties (300–800 K) show that K filling does not lower thermal conductivity much in comparison with AE or RE filling due to the relatively low mass of K atom. However, it improves electrical conductivity, retains large Seebeck coefficient, and leads to a reasonably good thermoelectric performance for the filled skutterudites. The maximum figure of merit ZT reaches 1 at 800 K for K0.38Co4Sb12.
Show PACS
81.05.Bx Metals, semimetals, and alloys
72.15.Jf Thermoelectric and thermomagnetic effects
72.15.Eb Electrical and thermal conduction in crystalline metals and alloys

Multiple transmission bands through metal films perforated with two periodic arrays of apertures

Yong-Hong Ye, Zhi-Bing Wang, Desheng Yan, and Jia-Yu Zhang

Appl. Phys. Lett. 89, 221108 (2006); http://dx.doi.org/10.1063/1.2397540 (3 pages) | Cited 4 times

Online Publication Date: 28 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors report experimental results of optical transmission through metal films perforated with two periodic arrays of subwavelength holes in the middle-infrared region. Multiple transmission bands can be achieved by such single-layer structured metal film, and their locations were controlled independently by the periodicities of the individual hole arrays. The coupling between surface plasmon polaritons in the cascaded structure is also studied.
Show PACS
78.66.Bz Metals and metallic alloys
68.55.-a Thin film structure and morphology
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)

Directional edge-emitting UV random laser diodes

Eunice S. P. Leong, S. F. Yu, and S. P. Lau

Appl. Phys. Lett. 89, 221109 (2006); http://dx.doi.org/10.1063/1.2397551 (3 pages) | Cited 35 times

Online Publication Date: 28 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors have achieved directional coherent random lasing from p-GaN/i-ZnO–SiO2 nanocomposite/n-ZnO heterojunction diodes. This is due to the use of relatively low refractive indexed carrier injection layers (i.e., cladding layers) and relatively high refractive indexed intrinsic layer with stripes of ZnO clusters (i.e., core layer) that allows the transverse confinement of in-plane closed-loop random cavities. Hence, directional lasing emission can be observed from the edge of the diodes. However, the choice of highly concentrated ZnO clusters, which is supposed to enhance the transverse confinement and optical gain, is not preferred for the fabrication of intrinsic layer. This is because the influence of corrugation effect (i.e., strong surface scattering) supersedes the transverse optical confinement of the diodes.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.55.Zz Random lasers
42.60.By Design of specific laser systems
42.72.Bj Visible and ultraviolet sources

High accuracy optical characterization of anisotropic liquids by merging standard techniques

V. Tkachenko, G. Abbate, A. Marino, F. Vita, M. Giocondo, A. Mazzulla, and L. De Stefano

Appl. Phys. Lett. 89, 221110 (2006); http://dx.doi.org/10.1063/1.2397553 (3 pages) | Cited 5 times

Online Publication Date: 28 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The design and fabrication of active and passive hybrid photonic devices, with tunable optical properties, based on liquid crystals require a very accurate knowledge of their anisotropic refractive indices up to 100 ppm in the wavelength region of interest. At this aim, the authors have integrated two standard optical techniques commonly used in liquid crystals characterization, the variable angle spectroscopic ellipsometry and the half leaky guided mode spectroscopy, exploiting their best performances and overcoming their limits. The dispersion curves of nematic liquid crystal E7 have been estimated in the 450–1700 nm wavelength interval with both precision and accuracy of 10−4.
Show PACS
42.70.Df Liquid crystals
61.30.-v Liquid crystals
07.60.Fs Polarimeters and ellipsometers

Positioning cavity solitons with a phase mask

F. Pedaci, P. Genevet, S. Barland, M. Giudici, and J. R. Tredicce

Appl. Phys. Lett. 89, 221111 (2006); http://dx.doi.org/10.1063/1.2388867 (3 pages) | Cited 20 times

Online Publication Date: 28 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Nonlinear interaction between a coherent electric field and a semiconductor medium inside a high Fresnel number cavity may give rise to the formation of cavity solitons. It is theoretically predicted that the position of these structures, mutually independent and bistable, can be controlled by gradients in the injection beam. Using a liquid crystal light valve to spatially modulate the phase of a coherent beam injected into a broad area vertical cavity semiconductor laser, the authors create reconfigurable arrays of cavity solitons. Fast time scales associated with semiconductor lasers and plasticity of localized structures suggest their potential for optical data processing.
Show PACS
42.65.Tg Optical solitons; nonlinear guided waves
42.79.Hp Optical processors, correlators, and modulators
42.79.Kr Display devices, liquid-crystal devices
42.55.Px Semiconductor lasers; laser diodes

Observation of random lasing in gold-silica nanoshell/water solution

Jin U. Kang

Appl. Phys. Lett. 89, 221112 (2006); http://dx.doi.org/10.1063/1.2397546 (3 pages) | Cited 6 times

Online Publication Date: 29 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The author reports experimental observation of resonant surface plasmon enhanced random lasing in gold-silica nanoshells in de-ionized water. The gold-silica nanoshell/water solution with concentration of 8×109 particles/ml was pumped above the surface plasmon resonance frequency using 514 nm argon-krypton laser. When pumping power was above the lasing threshold, sharp random lasing peaks occurred near and below the plasmon peak from 720 to 860 nm with a lasing linewidth less than 1 nm.
Show PACS
42.55.Zz Random lasers
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)

Electron spin coherence in n-doped CdTe/CdMgTe quantum wells

R. Bratschitsch, Z. Chen, S. T. Cundiff, E. A. Zhukov, D. R. Yakovlev, M. Bayer, G. Karczewski, T. Wojtowicz, and J. Kossut

Appl. Phys. Lett. 89, 221113 (2006); http://dx.doi.org/10.1063/1.2397552 (3 pages) | Cited 6 times

Online Publication Date: 29 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The spin coherence of a two-dimensional electron gas (2DEG) at different densities in CdTe/Cd0.85Mg0.15Te quantum wells has been examined by the time-resolved Kerr rotation technique using resonant excitation of either trions or excitons. The formation of negatively charged trions, either excited resonantly or via exciton states, causes strong spin polarization of the 2DEG. This effect leads to a long lasting exponential decay in the nanosecond regime. Spin dephasing times T2* of the 2DEG measured as a function of electron density up to 2.4×1011 cm−2 show a nonmonotonic behavior with a maximum at 8×1010 cm−2.
Show PACS
72.25.-b Spin polarized transport
73.63.Hs Quantum wells
42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
73.21.Fg Quantum wells
71.35.-y Excitons and related phenomena

Method based on atomic photoionization for spot-size measurement on focused soft x-ray free-electron laser beams

A. A. Sorokin, A. Gottwald, A. Hoehl, U. Kroth, H. Schöppe, G. Ulm, M. Richter, S. V. Bobashev, I. V. Domracheva, D. N. Smirnov, K. Tiedtke, S. Düsterer, J. Feldhaus, U. Hahn, U. Jastrow, et al.

Appl. Phys. Lett. 89, 221114 (2006); http://dx.doi.org/10.1063/1.2397561 (3 pages) | Cited 17 times

Online Publication Date: 29 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A method has been developed and applied to measure the beam waist and spot size of a focused soft x-ray beam at the free-electron laser FLASH of the Deutsches Elektronen-Synchrotron in Hamburg. The method is based on a saturation effect upon atomic photoionization and represents an indestructible tool for the characterization of powerful beams of ionizing electromagnetic radiation. At the microfocus beamline BL2 at FLASH, a full width at half maximum focus diameter of (15±2) μm was determined.
Show PACS
41.60.Cr Free-electron lasers
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation
07.85.Fv X- and γ-ray sources, mirrors, gratings, and detectors

CH4 monitoring in ambient air by communication band laser diode based difference frequency generation in a quasi-phase-matched LiNbO3 waveguide

Tsutomu Yanagawa, Osamu Tadanaga, Katsuaki Magari, Yoshiki Nishida, Hiroshi Miyazawa, Masaki Asobe, and Hiroyuki Suzuki

Appl. Phys. Lett. 89, 221115 (2006); http://dx.doi.org/10.1063/1.2397565 (3 pages) | Cited 10 times

Online Publication Date: 29 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Methane in ambient air is detected by difference frequency generation in a direct-bonded quasi-phase-matched LiNbO3 ridge waveguide using near infrared communication band laser diodes as pump and signal sources. Absorption lines for the Q branch in the 3.3 μm ν3 band are measured by using a Hanst configuration multipass cell with a 107 m path length. The authors detect 35 ppb CH4 in 2 kPa ambient air with a single wavelength scan of a signal external cavity laser diode by suppressing various spectroscopic fringes and stabilizing the pump laser diode oscillation mode with a fiber Bragg grating.
Show PACS
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
82.80.-d Chemical analysis and related physical methods of analysis
42.62.Eh Metrological applications; optical frequency synthesizers for precision spectroscopy
42.79.Gn Optical waveguides and couplers

Nonlinear inverse scattering and three-dimensional near-field optical imaging

George Y. Panasyuk, Vadim A. Markel, P. Scott Carney, and John C. Schotland

Appl. Phys. Lett. 89, 221116 (2006); http://dx.doi.org/10.1063/1.2396921 (3 pages) | Cited 9 times

Online Publication Date: 29 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The nonlinear inverse scattering problem for electromagnetic fields with evanescent components is considered. A solution to this problem is obtained in the form of a functional series expansion. The first term in the expansion corresponds to the pseudoinverse solution to the linearized inverse problem. The higher order terms represent nonlinear corrections to this result. Applications to the problem of three-dimensional optical imaging with subwavelength resolution are described and illustrated with numerical simulations.
Show PACS
87.63.L- Visual imaging
42.25.Fx Diffraction and scattering
42.30.Wb Image reconstruction; tomography

Impacts of intrinsic defects on luminescence properties of CuAlS2

Yuichiro Kuroki, Tomoichiro Okamoto, Masasuke Takata, and Minoru Osada

Appl. Phys. Lett. 89, 221117 (2006); http://dx.doi.org/10.1063/1.2400101 (3 pages) | Cited 1 time

Online Publication Date: 29 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors report on Raman scattering of CuAlS2 in order to study the influences of intrinsic defects on luminescence properties. The A1 mode is dominated in stoichiometric samples, whereas sulfur-poor conditions prepared at high temperatures ( ≥ 800 °C) cause defect-specific shift and broadening. They also find that additional mode (at 330 cm−1) caused by antisite defects is resonated at 2.16 eV excitation, in accordance with visible luminescence attributed to donor-acceptor pair (DAP) emission in photoluminescence. These results suggest that the DAP emissions may be caused by the defect complexes such as AlCu–VCu and VS–VCu, which reduces ultraviolet excitonic emission in this system.
Show PACS
78.55.Hx Other solid inorganic materials
78.30.Hv Other nonmetallic inorganics
61.72.J- Point defects and defect clusters
61.66.Bi Elemental solids
61.66.Dk Alloys
71.35.-y Excitons and related phenomena

Experimental confirmation of backscattering enhancement induced by a photonic jet

Alexander Heifetz, Kevin Huang, Alan V. Sahakian, Xu Li, Allen Taflove, and Vadim Backman

Appl. Phys. Lett. 89, 221118 (2006); http://dx.doi.org/10.1063/1.2398907 (3 pages) | Cited 24 times

Online Publication Date: 30 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The authors report experimental confirmation of backscattering enhancement induced by a photonic jet emerging from a dielectric sphere, a phenomenon recently predicted by theoretical solutions of Maxwell’s equations. To permit relatively straightforward laboratory measurements at microwave frequencies rather than visible light, they appropriately scaled the original conceptual dimensions of the dielectric microsphere and its adjacent perturbing nanoparticle (located within the microsphere’s photonic jet). Their experiments verified the existence of enhanced position-dependent backscattering perturbations by the adjacent particle. Their measured backscattering perturbations agreed well with prior theory and with additional finite-difference time-domain computational models of the complete microwave test geometry.
Show PACS
79.20.Ap Theory of impact phenomena; numerical simulation
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces

Acousto-optic-modulator-stabilized low-threshold mode-locked Nd:YVO4 laser

Aniruddha Ray, Susanta Kumar Das, Sourabh Mukhopadhyay, and Prasanta Kumar Datta

Appl. Phys. Lett. 89, 221119 (2006); http://dx.doi.org/10.1063/1.2399357 (3 pages) | Cited 1 time

Online Publication Date: 30 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A substantially low-threshold, kilohertz repetition rate and laser-diode-array pumped Nd:YVO4 laser, actively Q switched by an acousto-optic modulator and passively mode locked by a nonlinear mirror consisting of a KTiOPO4, second harmonic generating crystal, and a dichroic output coupler, is demonstrated with enhanced efficiency. The mode-locked pulses with a width of 11.5 ps lie underneath a Q-switched envelope having a width of 58 ns with a Q-switched modulation frequency of 40 kHz. For 10 W of pump power, a peak power of 719 kW is obtained under stable Q-switched and mode-locked operation, which is a marked improvement compared to the earlier reports.
Show PACS
42.55.Rz Doped-insulator lasers and other solid state lasers
42.60.Fc Modulation, tuning, and mode locking
42.60.By Design of specific laser systems
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.55.Xi Diode-pumped lasers

Oxygen induced strong green light emission from low-temperature grown amorphous silicon nitride films

Rui Huang, Kunji Chen, Bo Qian, San Chen, Wei Li, Jun Xu, Zhongyuan Ma, and Xinfan Huang

Appl. Phys. Lett. 89, 221120 (2006); http://dx.doi.org/10.1063/1.2399393 (3 pages) | Cited 14 times

Online Publication Date: 30 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Luminescent amorphous silicon nitride films were fabricated by plasma-enhanced chemical vapor deposition at room temperature followed by thermal oxidation at 100 °C. Very bright green emissions were clearly observed with the naked eye in a bright room after the samples had been oxidized. The emission peak is located at 495 nm. Fourier-transform infrared absorption spectra and results of depth profiling with x-ray photoelectron spectroscopy indicate that the introduction of oxygen is of a key role in enhancing the photoluminescence intensity of the films. Emission and excitation spectra analyses suggest that the green emission is originated from the radiative recombination in the localized states related to the Si–O bonds.
Show PACS
78.66.Jg Amorphous semiconductors; glasses
78.55.Hx Other solid inorganic materials
78.35.+c Brillouin and Rayleigh scattering; other light scattering
79.60.Bm Clean metal, semiconductor, and insulator surfaces

Suppression of transmission minima and maxima with structured metal surface

Qian-Jin Wang, Cheng-Ping Huang, Jia-Qi Li, and Yong-Yuan Zhu

Appl. Phys. Lett. 89, 221121 (2006); http://dx.doi.org/10.1063/1.2400098 (3 pages) | Cited 8 times

Online Publication Date: 30 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Extraordinary optical transmission through perforated metal films has received much attention recently. In this letter, the authors propose a method for studying the transmission properties, in which the Fourier coefficient of reciprocal lattice vectors is manipulated. Especially, due to a zero Fourier coefficient, the suppression of transmission minima and maxima has been experimentally observed. The results open a way to tailor the transmission properties of light.
Show PACS
78.66.Bz Metals and metallic alloys

30 nm resolution x-ray imaging at 8 keV using third order diffraction of a zone plate lens objective in a transmission microscope

Gung-Chian Yin, Yen-Fang Song, Mau-Tsu Tang, Fu-Rong Chen, Keng S. Liang, Frederick W. Duewer, Michael Feser, Wenbing Yun, and Han-Ping D. Shieh

Appl. Phys. Lett. 89, 221122 (2006); http://dx.doi.org/10.1063/1.2397483 (3 pages) | Cited 44 times

Online Publication Date: 1 December 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A hard x-ray transmission microscope with 30 nm spatial resolution has been developed employing the third diffraction order of a zone plate objective. The microscope utilizes a capillary type condenser with suitable surface figure to generate a hollow cone illumination which is matched in illumination range to the numerical aperture of the third order diffraction of a zone plate with an outmost zone width of 50 nm. Using a test sample of a 150 nm thick gold spoke pattern with finest half-pitch of 30 nm, the authors obtained x-ray images with 30 nm resolution at 8 keV x-ray energy.
Show PACS
07.85.Tt X-ray microscopes
back to top
RSS Feeds

Confinement of nonequilibrium plasmas in microcavities with diamond or circular cross sections: Sealed arrays of Al/Al2O3/glass microplasma devices with radiating areas above 20 cm2

S.-J. Park, K. S. Kim, A. Y. Chang, L. Z. Hua, J. C. Asinugo, T. Mehrotra, T. M. Spinka, and J. G. Eden

Appl. Phys. Lett. 89, 221501 (2006); http://dx.doi.org/10.1063/1.2393024 (3 pages) | Cited 4 times

Online Publication Date: 29 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Arrays of Al/Al2O3/glass microplasma devices with microcavities having diamond or circular cross-sectional geometries and radiating (active) areas >20 cm2 have been operated sealed-off in Ne, Ar, and Ar/D2 gas mixtures. Microcavities are fabricated in only one of the two electrodes, and the thickness of the completed package is ∼ 170 μm (excluding the quartz output window). Excited by a sinusoidal 20 kHz voltage wave form, arrays with active areas of 4.5×3 cm2 exhibit ignition voltages as low as 110±5 V rms for Ne pressures of 400–700 Torr. Mixtures of 1% D2 in Ar at a total pressure of 300 Torr produce wavelength-integrated (λ ∼ 250–400 nm) intensities of ∼ 1 mW cm−2 over a 25 cm2 area. Optical micrographs show the operation of the microplasmas in two well-defined modes. For current densities below a threshold value ( ∼ 53 mA cm−2 for 250 μm dia. cavities and pNe = 400 Torr), diffuse uniform plasma is produced in each cavity but, with higher currents, a positive column having near-cylindrical geometry appears, as evidenced by the generation of intense emission localized in the region of weak electric field gradient near the axis of symmetry.
Show PACS
52.75.-d Plasma devices
52.58.Qv Electrostatic and high-frequency confinement
52.25.Os Emission, absorption, and scattering of electromagnetic radiation
52.70.Kz Optical (ultraviolet, visible, infrared) measurements
52.50.Dg Plasma sources
52.80.Yr Discharges for spectral sources (including inductively coupled plasma)

Observation of femtosecond-laser-induced ablation plumes of aluminum using space- and time-resolved soft x-ray absorption spectroscopy

Yasuaki Okano, Katsuya Oguri, Tadashi Nishikawa, and Hidetoshi Nakano

Appl. Phys. Lett. 89, 221502 (2006); http://dx.doi.org/10.1063/1.2398931 (3 pages) | Cited 7 times

Online Publication Date: 30 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The dynamics of the laser ablation plume expansion of aluminum was investigated by using space- and time-resolved soft x-ray absorption spectroscopy. Blueshifts of the Al L-shell photoabsorption edge indicating the state of aluminum were observed in the plumes, which were generated by irradiating an aluminum target with 120 fs near-infrared pulses at an intensity of 1014 W/cm2. The spatiotemporal evolution of the plumes exhibited a multilayer structure consisting of vaporized aluminum and condensed aluminum particles, following the expansion of plasma, with expansion velocities of 104 m/s for the atomic state and 103 m/s for the condensed state.
Show PACS
79.20.Ds Laser-beam impact phenomena
52.38.Mf Laser ablation
52.50.Jm Plasma production and heating by laser beams (laser-foil, laser-cluster, etc.)
52.70.Kz Optical (ultraviolet, visible, infrared) measurements

Dispersion and transitions of dipolar plasmon modes in graded plasmonic waveguides

J. J. Xiao, K. Yakubo, and K. W. Yu

Appl. Phys. Lett. 89, 221503 (2006); http://dx.doi.org/10.1063/1.2396905 (3 pages) | Cited 5 times

Online Publication Date: 30 November 2006

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Coupled plasmon modes are studied in graded plasmonic waveguides, which are periodic chains of metallic nanoparticles embedded in a host with gradually varying refractive indices. The authors identify three types of localized modes called “light,” “heavy,” and “light-heavy” plasmonic gradons outside the passband, according to various localizations. The authors also demonstrate different transitions among extended and localized modes when the interparticle separation d is smaller than a critical dc, whereas the three types of localized modes occur for d>dc, with no extended modes. The transitions can be explained with phase diagrams constructed for the lossless metallic systems.
Show PACS
78.67.Bf Nanocrystals, nanoparticles, and nanoclusters
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
42.79.Gn Optical waveguides and couplers
63.20.Pw Localized modes
81.30.Bx Phase diagrams of metals, alloys, and oxides
Page 1 of 7 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close