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

5 May 2008

Volume 92, Issue 18, Articles (18xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 92, 182104 (2008); http://dx.doi.org/10.1063/1.2917705 (3 pages)

Jiang Chen, Yibin Hu, Ke Xia, and Zhongshui Ma
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds

Electronic structure and optical gain of wurtzite ZnO nanowires

Xiu-Wen Zhang, Jingbo Li, Shu-Shen Li, and Jian-Bai Xia

Appl. Phys. Lett. 92, 181101 (2008); http://dx.doi.org/10.1063/1.2918445 (3 pages) | Cited 1 time

Online Publication Date: 5 May 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The electronic structure and optical gain of wurtzite ZnO nanowires are investigated in the framework of effective-mass envelope-function theory. We found that as the elliptical aspect ratio e increases to be larger than a critical value, the hole ground states may change from optically dark to optically bright. The optical gain of ZnO nanowires increases as the hole density increases. For elliptical wire with large e, the y-polarized mode gain can be several thousand cm−1, while the x-polarized mode gain may be 26 times smaller than the former, so they can be used as ultraviolet linearly polarized lasers.
Show PACS
73.22.-f Electronic structure of nanoscale materials and related systems
71.20.Nr Semiconductor compounds
71.18.+y Fermi surface: calculations and measurements; effective mass, g factor
42.55.Px Semiconductor lasers; laser diodes
78.67.-n Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures

Advanced light trapping management by diffractive interlayer for thin-film silicon solar cells

Philipp Obermeyer, Christian Haase, and Helmut Stiebig

Appl. Phys. Lett. 92, 181102 (2008); http://dx.doi.org/10.1063/1.2919727 (3 pages) | Cited 15 times

Online Publication Date: 5 May 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Thin-film silicon solar cells made of amorphous and microcrystalline silicon in tandem cell configuration enable high efficiency and low-cost production. Precise control of the absorption in each diode by a wavelength-selective and diffractive interlayer provides optimized current matching. For this purpose, intermediate reflectors with periodically textured interfaces are investigated. The propagation of electromagnetic waves is simulated using a three dimensional Maxwell solver which considers both near field and far field optics. Design rules for intermediate reflectors and textured interfaces are presented.
Show PACS
84.60.Jt Photoelectric conversion

Continuous wave operation of injectorless quantum cascade lasers at low temperatures

Simeon Katz, Andrea Friedrich, Gerhard Boehm, and Markus-Christian Amann

Appl. Phys. Lett. 92, 181103 (2008); http://dx.doi.org/10.1063/1.2841704 (3 pages) | Cited 5 times

Online Publication Date: 6 May 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A continuous wave operating quantum-cascade-laser without injector is presented. The core design was taken from a low-threshold pulsed staircase laser. The active zone of one sample was optimized for low threshold current densities, using 60 periods and a low doping of 2.4×1010 cm−2/period. The second sample consists of 50 periods and a high doping of 6.3×1010 cm−2/period. For the first (second) sample, the threshold current density at 77 K for continuous operation was measured with 0.13 (0.24) kA/cm2 and maximum output power of 16.2 (22.7) mW was observed. Continuous operation was maintained up to 140 K for both lasers.
Show PACS
42.55.Px Semiconductor lasers; laser diodes

Terahertz-wave absorption in liquids measured using the evanescent field of a silicon waveguide

Li Cheng, Shin’ichiro Hayashi, Adrian Dobroiu, Chiko Otani, Kodo Kawase, Teruo Miyazawa, and Yuichi Ogawa

Appl. Phys. Lett. 92, 181104 (2008); http://dx.doi.org/10.1063/1.2916825 (3 pages) | Cited 6 times

Online Publication Date: 6 May 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A technique is presented for the measurement of the absorption properties of liquids in the terahertz wave range, based on the interaction between the liquid and the evanescent wave covering the surface of a cylindrical waveguide made of high-resistivity silicon. The terahertz wave propagates inside the waveguide as the fundamental EH11 mode. The presence of a medium around the silicon rod has a measurable effect on the overall end-to-end transmission of the waveguide. As demonstration, we report the measurements of a D-glucose aqueous solution with a concentration ranging from 0% to 45%, using a backward-wave oscillator as the terahertz wave source.
Show PACS
78.90.+t Other topics in optical properties, condensed matter spectroscopy and other interactions of particles and radiation with condensed matter (restricted to new topics in section 78)
61.25.Em Molecular liquids
41.20.Jb Electromagnetic wave propagation; radiowave propagation

Sensitized erbium emission from silicon-rich nitride/silicon superlattice structures

L. Dal Negro, R. Li, J. Warga, and S. N. Basu

Appl. Phys. Lett. 92, 181105 (2008); http://dx.doi.org/10.1063/1.2920435 (3 pages) | Cited 27 times

Online Publication Date: 7 May 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Erbium-doped silicon-rich nitride/silicon superlattice structures were fabricated by direct magnetron cosputtering deposition on Si substrates. Rapid thermal annealing resulted in the nucleation of small amorphous Si clusters, which efficiently sensitize 1.54 μm emission via a nanosecond-fast nonresonant energy transfer process, providing an alternative route toward the fabrication of Si-compatible devices based on Er sensitization.
Show PACS
81.15.Cd Deposition by sputtering
68.65.Cd Superlattices
61.72.Cc Kinetics of defect formation and annealing

Role of barrier layers in electroluminescence from SiN-based multilayer light-emitting devices

Rui Huang, Hengping Dong, Danqing Wang, Kunji Chen, Honglin Ding, Xiang Wang, Wei Li, Jun Xu, and Zhongyuan Ma

Appl. Phys. Lett. 92, 181106 (2008); http://dx.doi.org/10.1063/1.2920819 (3 pages) | Cited 16 times

Online Publication Date: 7 May 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the effects of barrier layer on the electroluminescence properties of the SiN-based multilayer light-emitting devices (LEDs). It is found that the emission efficiency is significantly enhanced by more than one order of magnitude compared to that of LED without barrier layer. Meanwhile, the emission wavelength can also be tuned from 620 to 510 nm by controlling the Si/N ratio of the barrier layer. The improved performance of LEDs can be attributed to the variation in the band offset between the Si-rich SiN well layer and the N-rich SiN barrier layer.
Show PACS
85.60.Jb Light-emitting devices

Laser action from Yb3+ ions in the ferroelectric and paraelectric phases of strontium barium niobate

E. Martín Rodríguez, D. Jaque, J. García Solé, and R. Pankrath

Appl. Phys. Lett. 92, 181107 (2008); http://dx.doi.org/10.1063/1.2924283 (3 pages) | Cited 8 times

Online Publication Date: 7 May 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on continuous wave laser oscillation of trivalent ytterbium ions in the frequency converter Yb3+:Sr0.6Ba0.4Nb2O6 ferroelectric laser crystal. Pump induced thermal loading has been used to drive the crystal from its ferroelectric to paraelectric phase. Stable laser radiation at 1070 nm was found in both phases while a bistable laser output is observed through phase transition. In addition, diffuse green (535 nm) radiation was generated by self-frequency doubling of the fundamental laser radiation because of the random distribution of microferroelectric domains existing in the ferroelectric as grown crystal.
Show PACS
42.60.By Design of specific laser systems
42.55.Rz Doped-insulator lasers and other solid state lasers
42.70.Hj Laser materials
42.65.Pc Optical bistability, multistability, and switching, including local field effects
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation

High peak power single frequency pulses using a short polarization-maintaining phosphate glass fiber with a large core

M. Leigh, W. Shi, J. Zong, Z. Yao, S. Jiang, and N. Peyghambarian

Appl. Phys. Lett. 92, 181108 (2008); http://dx.doi.org/10.1063/1.2917470 (3 pages) | Cited 14 times

Online Publication Date: 8 May 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report a high power, single frequency 1.5 μm pulsed fiber master oscillator-power amplifier laser source using a large core, polarization-maintaining phosphate glass fiber. The phosphate glass fiber produces high powers with low nonlinearities using high Er–Yb codoping and short length. Using this fiber, we were able to generate single frequency pulses with peak powers up to 51.5 kW. This is the highest reported peak pulse power for eye safe single frequency fiber laser systems.
Show PACS
42.81.Gs Birefringence, polarization
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation
42.70.Ce Glasses, quartz

Thin cell fringe-field-switching liquid crystal display with a chiral dopant

Zhibing Ge, Shin-Tson Wu, Seong Su Kim, Ji Woong Park, and Seung Hee Lee

Appl. Phys. Lett. 92, 181109 (2008); http://dx.doi.org/10.1063/1.2918838 (3 pages) | Cited 15 times

Online Publication Date: 8 May 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A fringe-field-switching (FFS) liquid crystal display (LCD) using a thin cell doped with a reverse-handed chiral compound is proposed. Such a FFS LCD exhibits a fast response time ( ∼ 8 ms), high transmittance (>90%), low operating voltage (5 Vrms), and intrinsically wide viewing angle. Its application for LCD televisions in order to reduce image blurring is emphasized.
Show PACS
42.79.Kr Display devices, liquid-crystal devices
85.60.Pg Display systems

Phasematching in semiconductor nonlinear optics by linear long-period gratings

Alex Hayat, Yotam Elor, Eran Small, and Meir Orenstein

Appl. Phys. Lett. 92, 181110 (2008); http://dx.doi.org/10.1063/1.2918013 (3 pages) | Cited 9 times

Online Publication Date: 9 May 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We experimentally demonstrate a phasematching technique for frequency conversion in nonlinear semiconductor structures by employing linear long-period gratings. We designed a specific semiconductor photonic device for second harmonic generation using coupled-mode equations with parameters extracted from beam propagation method simulations. Optical frequency converters were fabricated according to the design with the main feature; linear long-period weak gratings imprinted on semiconductor waveguides, providing the required photon momentum difference for matching the phases of the different-wavelength photons. The measured nonlinear conversion efficiency and its spectrum comply with our theoretical predictions.
Show PACS
42.79.Nv Optical frequency converters
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
42.79.Dj Gratings
42.15.Eq Optical system design
42.65.Wi Nonlinear waveguides
42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials

A terahertz quantum cascade laser grown by low-pressure metalorganic vapor phase epitaxy

Lorenzo Sirigu, Alok Rudra, Eli Kapon, Maria I. Amanti, Giacomo Scalari, and Jérôme Faist

Appl. Phys. Lett. 92, 181111 (2008); http://dx.doi.org/10.1063/1.2924294 (3 pages) | Cited 9 times

Online Publication Date: 9 May 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Demonstration of a terahertz quantum cascade laser grown by a low-pressure metalorganic vapor phase epitaxy is reported. The structural analysis of the grown structure shows a very high degree of vertical uniformity and sharp interfaces. Lasing emission at λ = 90 μm up to 93 K with a threshold current density Jth = 330 A/cm2 at 7 K was obtained in a structure incorporating a single plasmon waveguide.
Show PACS
42.55.Px Semiconductor lasers; laser diodes

Irreversible redshift of transmission spectrum of gold nanoparticles doped in liquid crystals

Li-Hsuan Hsu, Kuang-Yao Lo, Shih-An Huang, Chi-Yen Huang, and Chung-Sung Yang

Appl. Phys. Lett. 92, 181112 (2008); http://dx.doi.org/10.1063/1.2926658 (3 pages) | Cited 6 times

Online Publication Date: 9 May 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The absorption peak of gold (Au) nanoparticles doped in liquid crystal (ANDLC) is controllable by applying an external applied voltage before aggregation occurs. Au nanoparticles aggregate when the dielectrophoresis force, which is induced by the gradient of the square of the electric filed close to the sides of the host liquid crystal cell, overcomes the viscosity between Au nanoparticles and the LCs. This result leads to the irreversible redshift. A controllable filter with unpolarized light enables an ANDLC cell under the threshold voltage to prevent the aggregation effect.
Show PACS
61.30.Gd Orientational order of liquid crystals; electric and magnetic field effects on order
66.20.-d Viscosity of liquids; diffusive momentum transport
78.30.C- Liquids
78.40.Dw Liquids
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close