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881.
R. Yasuhara H. Kumigashira M. Oshima F. Guo T. Kinoshita K. Ono K. Ikeda Z. Liu 《Applied Surface Science》2008,254(15):4757-4761
We have applied the spectroscopic photoemission and low energy electron microscope to study high-k gate dielectrics and have performed the following in situ operations during ultrahigh vacuum annealing: real-time observation of surface morphology and microregion photoelectron spectroscopy measurements. Changes in surface morphology and electronic states were consistent with the models previously reported in the case of HfO2/Si. No clear differences between void regions and nonvoid regions have been observed in microregion photoelectron spectra for poly-Si/HfO2/Si, regardless of phase separation in real space. These results have suggested that the initial void formation occurs in about 100-nm wide regions for both HfO2/Si and poly-Si/HfO2/Si. 相似文献
882.
We propose some schemes for remote preparation of arbitraryhigh-dimensional equatorial entangled state via a single bipartitehigh-dimensional entangled state as quantum channel. We firstlypresent the remote preparation of bipartite three- and d-dimensionalequatorial entangled state by using a single entangled qutrit andqudit pair, respectively, and then directly generalize the schemesto multipartite case. The cases of the quantum channel beingnon-maximally two-qutrit and two-qudit entangled state are alsoconsidered, respectively. In these schemes the required resourcesare single-particle projective measurement, appropriate localunitary operation, auxiliary particle, and high-dimensional C-NOToperation. It is shown that the entanglement resource and classicalcommunication cost are both greatly reduced in our schemes. 相似文献
883.
Implementation of quantum controlled phase gate and preparation of multiparticle entanglement in cavity QED 下载免费PDF全文
Schemes are presented for realizing quantum controlled phase gate and preparing an N-qubit W-like state, which are based on the large-detuned interaction among three-state atoms, dual-mode cavity and a classical pulse. In particular, a class of W states that can be used for perfect teleportation and superdense coding is generated by only one step. Compared with the previous schemes, cavity decay is largely suppressed because the cavity is only virtually excited and always in the vacuum state and the atomic spontaneous emission is strongly restrained due to a large atom-field detuning. 相似文献
884.
Suppressing the hot carrier injection degradation rate in total ionizing dose effect hardened nMOSFETs 下载免费PDF全文
Annular gate nMOSFETs are frequently used in spaceborne integrated circuits due to their intrinsic good capability of resisting total ionizing dose (TID) effect. However, their capability of resisting the hot carrier effect (HCE) has also been proven to be very weak. In this paper, the reason why the annular gate nMOSFETs have good TID but bad HCE resistance is discussed in detail, and an improved design to locate the source contacts only along one side of the annular gate is used to weaken the HCE degradation. The good TID and HCE hardened capability of the design are verified by the experiments for I/O and core nMOSFETs in a 0.18 μm bulk CMOS technology. In addition, the shortcoming of this design is also discussed and the TID and the HCE characteristics of the replacers (the annular source nMOSFETs) are also studied to provide a possible alternative for the designers. 相似文献
885.
CHEN Chang-Yong 《理论物理通讯》2012,(5):649-652
We study the influence of multi-photon processes on the geometric quantum computation in the systems of superconducting qubits based on the displacement-like and the general squeezed operator methods. As an example, we focus on the question about how to implement a two-qubit geometric phase gate using superconducting circuit quantum electrodynamics with both single- and two-photon interaction between the qubits and the cavity modes. We find that the multiphoton processes are not only controllable but also improve the gating speed. The comparison with other physical systems and experimental feasibility are discussed in detail. 相似文献
886.
铁电材料作为感光功能薄膜的红外器件研究近年来十分活跃,其良好的压电、铁电、热释电、光电及非线性光学特性以及能够与半导体工艺相集成等特点,在微电子和光电子技术领域有着广阔的应用前景。实验将铁电材料锆钛酸铅作为感光层与GaN基高电子迁移率晶体管(HEMT)相结合,成功地制备出了感光栅极GaN基HEMT器件,并在波长为365 nm的光照下进行探测,经大量实验测试后发现器件在该波段的光照下饱和电流达到28 mA,相比无光照时饱和电流提高12 mA。另外,通过合理改变器件结构尺寸,包括器件栅长以及栅漏间距,发现随着栅长的增大,器件的饱和输出电流依次减小,而栅漏间距的变化对阈值电压以及饱和电流的影响并不大。由此可知,改变器件结构参数可以达到提高器件性能的目的并且可以提高探测效率。 相似文献
887.
Chirantan Gayen Upashi Goswami Kasturi Gogoi Srestha Basu Anumita Paul 《Chemphyschem》2019,20(7):953-958
Herein, we report the construction of intracellular logic operations using luminescent histidine stabilized gold nanoclusters (His Au NCs). The luminescence intensity of His Au NCs was found to be significantly enhanced following interaction with zinc ions, owing to “Crystallization induced emission enhancement”. Further, the luminescence intensity of His Au NCs was found to be effectively quenched in presence of sulphide ions, owing to transformation of emissive His Au NCs to non-emissive gold nanoparticles. Thus, the collective and individual effects of zinc ions and sulphide ions causing significant variation in the luminescence intensity of His Au NCs, were used as input parameters for construction of intracellular logic operations such as Tri state buffer, “on-off” switch and INHIBIT gate within mammalian cells. 相似文献
888.
889.
WANG Yan-Hui ZHANG Yong 《理论物理通讯》2008,49(6):1487-1490
Using cluster state and single qubit measurement one can perform the one-way quantum computation. Here we give a detailed scheme for realizing a modified Grover search algorithm using measurements on cluster state. We give the measurement pattern for the cluster-state realization of the algorithm and estimated the number of measurement needed for its implementation. It is found that O(2^3n/^2n^2) number of single qubit measurements is required for its realization in a cluster-state quantum computer. 相似文献
890.
V. G. Shcherbitskii V. É. Kisel' A. V. Podlipenskii M. I. Demchuk N. V. Kuleshov V. I. Levchenko V. N. Yakimovich M. Mond S. Kück G. Huber B. I. Denker S. E. Sverchkov 《Journal of Applied Spectroscopy》2002,69(2):254-259
The spectroscopic properties of Cr2+ ions in Cr:Cd1–x
Mn
x
Te (CMT) crystals are studied, and the possibility of using these impurity crystals as active media and saturable absorbers of solidstate lasers of medium IR range is demonstrated. The bands of absorption with a maximum at 1.9 m and of luminescence with a maximum at 2.6 m correspond to the transitions between the levels 5
T
2 and 5
E of the tetracoordinated Cr2+ ions with more than 1·10–18cm2 cross sections. The pulsed and continuous lasing modes of a Cr:CMT laser are realized in the 2.6m region. The Cr:CMT crystals are characterized by effective saturation of impurity absorption. The cross sections of absorption from the ground and excited states of the Cr2+ ions at = 2.09 m are determined: gsa = 1.1·10–18 cm2; esa/gsa < 0.1. With the use of the Cr:CMT crystals as a passive gate the regime of Qswitching of the Cr,Tm,Ho:YAG laser emitting at = 2.09 m is obtained. 相似文献