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991.
992.
We propose a pushing gate for entangling two ions in a planar Coulomb crystal in the view of realizing large-scale quantum simulations. A tightly focused laser is irradiated from the direction perpendicular to the crystal plane and its spatial intensity profile generates a state-dependent force. We analyze the error sources in this scheme and obtain low infidelity. 相似文献
993.
Chan M. Lim 《Optics Communications》2010,283(7):1553-1557
Highly-directive light-emitting diodes showing high extraction efficiency are designed and demonstrated based on a two-dimensional super-periodic photonic-crystal structure. With this specific design, a super-periodic photonic-crystal structure can generate a highly directional beam by satisfying the multiple-resonance conditions of distributed Bragg reflectors and the topmost slab. Dependence of the power efficiency on the thickness of the topmost slab and the etching depth of the photonic-crystal holes is then analyzed by the three-dimensional finite-difference time-domain method. From subsequent analyses, it has been determined that >80% of the extracted power could be funneled into a small divergence angle of 30°. 相似文献
994.
FU WangYang LIU Lei WANG WenLong WU MuHong XU Zhi BAI XueDong & WANG EnGe Beijing National Laboratory for Condensed Matter Physics 《中国科学:物理学 力学 天文学(英文版)》2010,(5)
Carbon nanomaterials,including the one-dimensional(1-D) carbon nanotube(CNT) and two-dimensional(2-D) graphene,are heralded as ideal candidates for next generation nanoelectronics.An essential component for the development of advanced nanoelectronics devices is processing-compatible oxide.Here,in analogy to the widespread use of silicon dioxide(SiO2) in silicon microelectronic industry,we report the proof-of-principle use of graphite oxide(GO) as a gate dielectrics for CNT field-effect transistor(FET) via a... 相似文献
995.
J. H. Han 《Opto-Electronics Review》2008,16(2):185-188
Improvement in frequency bandwidth of a packaged diode laser is investigated by the circuit impedance matching. To overcome
the structural limitation of the electronic package for high frequencies, employing conventional lumped element impedance
matching technique in conjunction with the manipulation of signal path of the package connections showed significant enhancement
for 3-dB bandwidth to more than 6 GHz. 相似文献
996.
An ultrathin poly(methyl methacrylate) (PMMA) buffer layer was developed to improve the performance of n‐channel organic thin‐film transistors (OTFTs). The 8 nm‐thick PMMA film, prepared by spin‐coating, provided a very smooth surface and a uniform coverage on SiO2 surface reproducibly, which was confirmed by X‐ray reflectivity (XR) measurement. Then, we fabricated N,N′‐ditridecyl‐3,4,9,10‐perylenetetracarboxylic diimide (PTCDI‐C13) thin‐film transistors with and without this 8 nm‐thick PMMA insulating layer on SiO2 gate insulators and achieved one‐order increase of field‐effect mobility (up to 0.11 cm2/(Vs) in a vacuum), one‐half decrease of threshold voltage, and reduction of current hysteresis with the PMMA layer. Only TFTs with the PMMA layer displayed n‐channel operation in air and showed field‐effect mobility of 0.10 cm2/(Vs). We consider that electrical characteristics of n‐channel OTFTs were considerably improved because the ultrathin PMMA film could effectively passivate the SiO2 insulator surface and decrease interfacial electron traps. This result suggests the importance of the ultrathin PMMA layer for controlling the interfacial state at the semiconductor/insulator interface and the device characteristics of OTFTs. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
997.
Mustafa M. Musameh Daniela Klink Jonghyun Choi Yen Bach Truong Ilias Louis Kyratzis 《Electroanalysis》2012,24(5):1207-1211
In this work, GC electrodes modified with thick electrospun nanofibrous Nafion webs were characterized using scanning electron microscopy (SEM) and cyclic voltammetry (CV) and used for the extraction and electrochemical detection of cadmium by differential pulse voltammetry. Cadmium was detected after 10 min incubation at open circuit followed by anodic stripping using 60 s reduction at ?1.4 V. The electrode yielded well‐defined, undistorted and reproducible (RSD of 7.0 % based on 10 measurements) voltammetric response with two linear ranges from 0.1 to 3 µM (R2=0.994 ) and from 3 to 10 µM (R2=0.977) and a detection limit and sensitivity of 0.01 µM and 32 and 7.725 µA/µM for both linear portions of the curve respectively. 相似文献
998.
Mapping equivalent approach to analysis and realization of memristor-based dynamical circuit
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A novel mapping equivalent approach is proposed in this paper, which can be used for analyzing and realizing a memristor-based dynamical circuit equivalently by a nonlinear dynamical circuit with the same topologies and circuit parameters. A memristor-based chaotic circuit and the corresponding Chua’s chaotic circuit with two output differentiators are taken as examples to illustrate this approach. Equivalent dynamical analysis and realization of the memristor-based chaotic circuit are performed by using Chua’s chaotic circuit. The results indicate that the outputs of memristor-based chaotic circuit and the corresponding outputs of Chua’s chaotic circuit have identical dynamics. The proposed approach verified by numerical simulations and experimental observations is useful in designing and analyzing memristor-based dynamical circuits. 相似文献
999.
Optical switch fabric plays an important role in building multiple-user optical quantum communication networks.Owing to its self-routing property and low complexity, a banyan network is widely used for building switch fabric. While,there is no efficient way to remove internal blocking in a banyan network in a classical way, quantum state fusion, by which the two-dimensional internal quantum states of two photons could be combined into a four-dimensional internal state of a single photon, makes it possible to solve this problem. In this paper, we convert the output mode of quantum state fusion from spatial-polarization mode into time-polarization mode. By combining modified quantum state fusion and quantum state fission with quantum Fredkin gate, we propose a practical scheme to build an optical quantum switch unit which is block free. The scheme can be extended to building more complex units, four of which are shown in this paper. 相似文献
1000.
Artificial ear is being used to evaluate the acoustic response and the sound quality of the mobile telephony devices, which simulates the practical listening condition of the outer ears. In this paper, a method to estimate the coupled acoustic response of the device with an artificial ear is studied to be effectively used in the design. To this end, an equivalent circuit model of the total receiver system including all accessory elements is established. Acoustic impedance of artificial ear, which is essential in the equivalent model, is directly measured by using three microphones arranged in tandem on the duct wall connected to the artificial ear. Input impedances of two artificial ears, Type 3.3 and 3.4, which are currently employed as the standard devices, are measured. The measured data is incorporated into the model to predict the acoustic response. To validate the proposed model using the measured impedance, the measured acoustic responses of two simulation systems including mobile phone and artificial ear are compared with the predicted ones. A reasonably good agreement between measurement and prediction is observed, and their difference is less than 4.5 dB at the narrow communication band for a mobile phone (f < 3.4 kHz). It is also found that the input impedance of Type 3.3 ear is more robust to the change of measuring condition than Type 3.4 ear. 相似文献