JAP: Device Physics http://scitation.aip.org/ JAP: Device Physics InAs/InAsSb strain balanced superlattices for optical detectors: Material properties and energy band simulations http://link.aip.org/link/?JAP/111/034507/1&agg=rss D. Lackner, M. Steger, M. L. W. Thewalt, O. J. Pitts, Y. T. Cherng et al.<br/> InAsSb/InAs type II strain balanced superlattices lattice matched to GaSb have recently been proposed as an alternative to InAs/(In)GaSb short period superlattices for mid- to long infrared photodetectors. Photoluminescence data at 4 K of OMVPE grown InAsSb (multi-) quantum wells in an InAs matrix o ... [J. Appl. Phys. 111, 034507 (2012)] published Fri Feb 10, 2012. On the energy distribution of interface states and their relaxation time profiles in Al/pentacene/p-GaAs heterojunction diode http://link.aip.org/link/?JAP/111/034508/1&agg=rss Yasemin &#x015E;afak, Murat Soylu, Fahrettin Yakuphanoglu, and &#x015E;emsettin Alt&#x0131;ndal<br/> The energy density distribution profile of the interface states (N) and their relaxation time (tau) of Al/pentacene/p-GaAs heterojunction diodes were obtained from the admittance spectroscopy method, which is included in capacitance/conductance-voltage measurements in the frequency range of 10 kHz-1 ... [J. Appl. Phys. 111, 034508 (2012)] published Fri Feb 10, 2012. Magneto-resistance of organic spin valves due to spin-polarized tunnel injection and extraction of charge carriers http://link.aip.org/link/?JAP/111/034505/1&agg=rss A. Goswami, M. Yunus, P. P. Ruden, and D. L. Smith<br/> Spin-polarized tunnel injection and extraction of charge carriers can give rise to magneto-resistance in organic spin valves. To describe this magneto-resistance, the tunneling process is modeled as a transfer of electrons through a thin insulating layer between a ferromagnetic contact and an organi ... [J. Appl. Phys. 111, 034505 (2012)] published Mon Feb 6, 2012. Schottky barrier control gate-type carbon nanotube field-effect transistor biosensors http://link.aip.org/link/?JAP/111/034506/1&agg=rss Masuhiro Abe, Yasuhide Ohno, and Kazuhiko Matsumoto<br/> We propose a unique structure for carbon nanotube field-effect transistors (CNT-FETs/with a Schottky barrier control gate (SBC gate) to improve the sensitivity of CNT-FET biosensors. The performance of the new biosensors was compared with conventional devices with back gate-type CNT-FETs both throug ... [J. Appl. Phys. 111, 034506 (2012)] published Mon Feb 6, 2012. Impact ionization in quantum well infrared photodetectors with different number of periods http://link.aip.org/link/?JAP/111/034504/1&agg=rss Shan Dong, Ning Li, Sihai Chen, Xihui Liu, and Wei Lu<br/> This paper presents the detailed investigation of the photocurrent accompanied with impact ionization effect in InGaAs/GaAs multiple quantum well infrared photodetectors (QWIPs) with 10 and 50 periods. The sample with 50 periods exhibits remarkable enhancement at high electric field while a negative ... [J. Appl. Phys. 111, 034504 (2012)] published Fri Feb 3, 2012. Recombination lifetime of free polarons in polymer/fullerene bulk heterojunction solar cells http://link.aip.org/link/?JAP/111/034503/1&agg=rss Kejia Li, Lijun Li, and Joe C. Campbell<br/> The recombination lifetime of free polarons was measured using three different methods: electrical fielddependent photoresponse, transient photoconductivity, and forward-to-zero bias transient-current response. The average free polaron recombination lifetime is estimated to be a few microseconds for ... [J. Appl. Phys. 111, 034503 (2012)] published Thu Feb 2, 2012. Analytical solution for the photocurrent of solar cells with internal reflection http://link.aip.org/link/?JAP/111/034502/1&agg=rss Zhenli Wen<!--orlang--> (&#x95FB;&#x9707;&#x5229;)<!--orlang-->, Wenjing Wang<!--orlang--> (&#x738B;&#x6587;&#x9759;)<!--orlang-->, Chunlan Zhou<!--orlang--> (&#x5468;&#x6625;&#x5170;)<!--orlang-->, and Jun Zhang<!--orlang--> (&#x5F20;&#x4FCA;)<!--orlang--><br/> A 1 D analytical photocurrent expression of the base of a crystal silicon solar cell is derived for both the planar and the textured surfaces, with consideration of internal reflection. This expression separates the internal reflection effect from other effects in the photocurrent expression. The in ... [J. Appl. Phys. 111, 034502 (2012)] published Wed Feb 1, 2012. On the design and applicability of nanowire solar cells using low-grade semiconductors http://link.aip.org/link/?JAP/111/034501/1&agg=rss Majid Gharghi<br/> Nanowire based radial junction structure has been widely proposed to achieve high efficiency solar cells with low grade semiconductors, in particular silicon. We present a concise model based on the collection probability of photogenerated carriers to investigate the effect of size and geometry on t ... [J. Appl. Phys. 111, 034501 (2012)] published Wed Feb 1, 2012. Optical modeling and experimental verification of light induced phenomena in In-Ga-Zn-O thin film transistors with varying gate insulator thickness http://link.aip.org/link/?JAP/111/024511/1&agg=rss Yoon Jang Chung, Jeong Hwan Kim, Un Ki Kim, Sang Ho Rha, Eric Hwang et al.<br/> A simple optical model based on the transfer matrix method was used to simulate photon absorption in oxide semiconductor systems with varying insulator thickness in the thin film transistor (TFT) structure. For comparison with actual experimental results, hole current was measured in transparent met ... [J. Appl. Phys. 111, 024511 (2012)] published Mon Jan 30, 2012. Optimization of power and efficiency of thermoelectric devices with asymmetric thermal contacts http://link.aip.org/link/?JAP/111/024509/1&agg=rss Kazuaki Yazawa and Ali Shakouri<br/> We report the theoretical efficiency of thermoelectric power generation with asymmetric thermal contacts to reservoirs. A key ingredient is the electrical and thermal co-optimization. Generic formula of the maximum power output and the optimum leg length are obtained. The Curzon-Ahlborn limit at max ... [J. Appl. Phys. 111, 024509 (2012)] published Thu Jan 26, 2012. Interband cascade infrared photodetectors with enhanced electron barriers and p-type superlattice absorbers http://link.aip.org/link/?JAP/111/024510/1&agg=rss Z. Tian, R. T. Hinkey, Rui Q. Yang, D. Lubyshev, Y. Qiu et al.<br/> We present results on the optical and electrical performance of mid-infrared detectors based on interband-cascade structures. These devices include enhanced electron barriers, designed to suppress intraband-tunneling current between stages, and p-doped type-II InAs/GaSb superlattice absorbers. Withi ... [J. Appl. Phys. 111, 024510 (2012)] published Thu Jan 26, 2012. Rectification of elastic waves in a thin plate http://link.aip.org/link/?JAP/111/024507/1&agg=rss Yukihiro Tanaka, Takahiro Murai, and Norihiko Nishiguchi<br/> We propose a rectifier of elastic waves in a thin plate, which is made of an elastically isotropic material containing a periodic array of triangular holes as scatterers, and demonstrate numerically that it works both for the symmetric and anti-symmetric Lamb waves as well as shear horizontal waves. ... [J. Appl. Phys. 111, 024507 (2012)] published Wed Jan 25, 2012. Influence on electrical characteristics of the design of 4H-SiC ultraviolet photodetectors: Theoretical analysis and simulations http://link.aip.org/link/?JAP/111/024506/1&agg=rss Stephane Biondo, Wilfried Vervisch, Laurent Ottaviani, and Olivier Palais<br/> This paper deals with the simulation of the reverse current density of 4H-SiC ultraviolet- (UV) photodetector devices based on p-i-n diodes. Simulations using the finite-element method presented in this paper lead to an understanding of the photodetector current density levels in dark field, as well ... [J. Appl. Phys. 111, 024506 (2012)] published Wed Jan 25, 2012. Computational study of energy filtering effects in one-dimensional composite nano-structures http://link.aip.org/link/?JAP/111/024508/1&agg=rss Raseong Kim and Mark S. Lundstrom<br/> Possibilities to improve the Seebeck coefficient S versus electrical conductance G trade-off of diffusive composite nano-structures are explored using an electro-thermal simulation framework based on the non-equilibrium Green's function method for quantum electron transport and the lattice heat diff ... [J. Appl. Phys. 111, 024508 (2012)] published Wed Jan 25, 2012. Quantitative analysis of electroluminescence images from polymer solar cells http://link.aip.org/link/?JAP/111/024505/1&agg=rss Marco Seeland, Roland Rosch, and Harald Hoppe<br/> We introduce the micro-diode-model (MDM) based on a discrete network of interconnected diodes, which allows for quantitative description of lateral electroluminescence emission images obtained from organic bulk heterojunction solar cells. Besides the distributed solar cell description, the equivalen ... [J. Appl. Phys. 111, 024505 (2012)] published Mon Jan 23, 2012. Modeling of ferroelectric switching process in poly(vinylidene fluoride-trifluoroethylene) copolymer ultrathin films with electroactive interlayer http://link.aip.org/link/?JAP/111/024504/1&agg=rss Ying Hou, Xiuli Zhang, Yuan Zhang, Guoqiang Xu, and Haisheng Xu<br/> A universal model and experiments on the polarization switching for ferroelectric poly(vinylidene fluoride-trifluoroethylene) copolymer ultra-thin films with an interface layer have been studied. It is found that polarization switching could complete if the capacitance of the interface layer is larg ... [J. Appl. Phys. 111, 024504 (2012)] published Fri Jan 20, 2012. An improved model for non-resonant terahertz detection in field-effect transistors http://link.aip.org/link/?JAP/111/024502/1&agg=rss S. Preu, S. Kim, R. Verma, P. G. Burke, M. S. Sherwin et al.<br/> Transistors operating well above the frequencies at which they have gain can still rectify terahertz currents and voltages, and have attracted interest as room-temperature terahertz detectors. We show that such rectifying field-effect transistors may still be treated as a lumped element device in th ... [J. Appl. Phys. 111, 024502 (2012)] published Thu Jan 19, 2012. A multidentate lubricant for use in hard disk drives at sub-nanometer thickness http://link.aip.org/link/?JAP/111/024503/1&agg=rss X.-C. Guo, B. Marchon, R.-H. Wang, C. M. Mate, Q. Dai et al.<br/> We describe a second generation of multidentate lubricant structures for use on a magnetic media in a hard disk drive. Building on earlier work where a perfluoropolyether (PFPE) chain with hydroxyl bonding moieties were placed in the middle of the chain as well as on chain ends, creating a structure ... [J. Appl. Phys. 111, 024503 (2012)] published Thu Jan 19, 2012. The effect of salt on ion adsorption on a SiOx alignment film and reduced conductivity of a liquid crystal host http://link.aip.org/link/?JAP/111/024501/1&agg=rss Yi Huang, Achintya Bhowmik, and Philip J. Bos<br/> It is shown that the addition of salt to liquid crystal cells, using a SiOx alignment layer, can actually reduce the ion concentration. This seeming contradiction may be explained by the ability of salt to complex with water and to aid the drying of the liquid crystal material. The results show a pa ... [J. Appl. Phys. 111, 024501 (2012)] published Tue Jan 17, 2012. Photon recycling effect on electroluminescent refrigeration http://link.aip.org/link/?JAP/111/014511/1&agg=rss Kuan-Chen Lee and Shun-Tung Yen<br/> We study electroluminescent refrigeration in an AlGaAs/GaAs double heterostructure by a self-consistent calculation with photon recycling considered. To gain insight, we investigate the influence of the recycling on the carrier density and the current components due to various recombination mechanis ... [J. Appl. Phys. 111, 014511 (2012)] published Fri Jan 13, 2012. Percolation model for the threshold voltage of field-effect transistors with nanocrystalline channels http://link.aip.org/link/?JAP/111/014510/1&agg=rss I. P. Steinke and P. P. Ruden<br/> We present a model for determining the threshold voltage of field-effect transistors with nanocrystalline active channel layers. In this type of device, the multiple boundaries between neighboring crystalline grains limit the charge-carrier transport. Electrons in the channel may either populate the ... [J. Appl. Phys. 111, 014510 (2012)] published Thu Jan 12, 2012.