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101.
102.
Chia EE Zhu JX Talbayev D Averitt RD Taylor AJ Oh KH Jo IS Lee SI 《Physical review letters》2007,99(14):147008
We present studies of the photoexcited quasiparticle dynamics in Tl(2)Ba(2)Ca(2)Cu(3)O(y) (Tl-2223) using femtosecond optical techniques. Deep into the superconducting state (below 40 K), a dramatic change occurs in the temporal dynamics associated with photoexcited quasiparticles rejoining the condensate. This is suggestive of entry into a coexistence phase which, as our analysis reveals, opens a gap in the density of states (in addition to the superconducting gap), and furthermore, competes with superconductivity resulting in a depression of the superconducting gap. 相似文献
103.
Tsuji S Yoshinari Y Kawai E Nakajima K Park HS Shindo D 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2007,188(2):380-386
A new method of surface microscopy is proposed, which combines three-dimensional electron spin resonance imaging by magnetic resonance force microscopy (MRFM) and topographic imaging of the sample surface by scanning force microscopy (SFM). In order to demonstrate its potential for the identification of microscale objects, the individual and combined images are used to provide the locations, shapes and spin density distributions of target phantom objects. We report spatial resolution in MRFM of 2.8 x 2.8 x 2.0 microm(3). This could be improved to the theoretical limit of 0.08 x 0.08 x 0.04 microm(3) through reduction of the thermal noise by cooling to cryogenic temperatures approximately 0.5K. We believe that this type of microscopy will become a very useful tool for the investigation of anomalies induced in surfaces by materials buried below the surface. 相似文献
104.
Regenerative pulsation from whispering gallery modes excited by a continuous-wave laser beam is observed in silica microspheres that feature a diminishing thermal nonlinearity near 20 K. The regenerative pulsation arises from the competition between Kerr nonlinearity and the much reduced thermal nonlinearity, when the two nonlinearities with very different timescales are comparable in magnitude but opposite in sign. 相似文献
105.
Sul Lee Sunho Jeong Dongjo Kim Bong Kyun Park Jooho Moon 《Superlattices and Microstructures》2007,42(1-6):361
We have fabricated a solution-processed ZnO thin-film transistor without vacuum deposition. ZnO nanoparticles were prepared by the polyol method from zinc acetate, polyvinyl pyrrolidone, and diethyleneglycol. The solution-processable semiconductor ink was prepared by dispersing the synthesized ZnO in a solvent. Inverted stagger type thin-film transistors were fabricated by spin casting the ZnO ink on the heavily doped Si wafer with 200 nm thick SiO2, followed by evaporation of Cr/Au source and drain electrodes. After the drying and heat treatment at 600 C, a relatively dense ZnO film was obtained. The film characteristics were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). In order to obtain the electrical properties of the solution-derived transistor, the on–off ratio, threshold voltage, and mobility were measured. 相似文献
106.
Dong‐Won Lee Won‐Ju Cho Jun‐Kwang Song Oh‐Yun Kwon Won‐Hee Lee Chi‐Hong Park Kyung‐Eun Park Heesoo Lee Yong‐Nam Kim 《Progress in Photovoltaics: Research and Applications》2015,23(7):829-837
High‐temperature‐induced and humidity‐induced degradation behaviors were investigated through the failure analysis of encapsulated Cu(In,Ga)Se2 (CIGS) modules and non‐encapsulated CIGS cells. After being exposed to high temperature (85 °C) for 1000 h, the efficiency loss of CIGS modules and the resistivities of the aluminum‐doped zinc oxide (AZO) layer, CIGS layer, and Mo layer were slightly increased. After damp heat (DH) testing (85 °C/85% RH), the efficiency of some modules decreased significantly accompanied by discoloration, and in these areas, the resistivity of the AZO layers increased markedly. The causes of degradation of CIGS cells after high temperature and DH tests were suggested through X‐ray photoelectron spectroscopy analysis. The high‐temperature‐induced degradation behaviors were revealed to be increases in series resistance of the CIGS cells, due to the adsorption of oxygen on the AZO, CIGS, and Mo layers. The degradation behavior after DH (85 °C/85% RH) exposure was caused by the adsorption of oxygen, as well as the generation of Zn(OH)2 due to water molecules. In particular, the humidity‐induced degradation behavior in discolored CIGS modules was ascribed to the generation of Zn(OH)2 and carboxylic acids in the AZO layer, due to a chemical reaction between the AZO, ethylene‐vinyl acetate copolymer, and water. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
107.
Won Sang Chung 《Fortschritte der Physik》2015,63(6):331-336
In this paper we consider the ‐graded parity generalizing the ordinary (or Z2‐graded ) parity. Using the ‐graded parity operator, we discuss the minimal bosonization of the N=2 SUSY with ‐graded parity. The lowest energy level is shown to be infinitely degenerate. In order to avoid the infinite degeneracy of the ground state we introduce the paraboson algebra to obtain the para‐supersymmetry. Finally, we discuss the hidden SUSY with Z3‐graded parity. 相似文献
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