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991.
This research proposes a practical multiport optical circulator design by using polarizing beam splitter cubes as spatial walk-off polarizers. The use of Porro prisms for directing light requires fewer components and improves space-efficiency. Therefore, a high performance device can be produced at a reduced cost. A six-port optical circulator prototype was fabricated to show the feasibility of the proposed design. The insertion losses range between 0.52 and 1.05 dB, the isolations range between 26.20 and 45.13 dB, and the return losses are 27.72 dB. The benefits of this design's simple and symmetrical structure include cost-efficiency, simple fabrication processes, polarization-independence, the resolve of polarization-mode dispersion issues, and high performance. Additionally, the number of ports can be increased easily. 相似文献
992.
The current–voltage characteristics and photoresponse of mesa structured {111}‐oriented homoepitaxial CVD diamond p(i)n‐junctions with different intrinsic layer thickness are investigated. When a sufficiently thick intrinsic layer is present, a rectification ratio of 108 at ±10 V could be obtained. Good rectifying diodes show a high photoresponse ratio between 210 nm (above bandgap) and 500 nm (below bandgap), making them suitable for UV detection purposes. The results are compared with similar measurements carried out on polycrystalline CVD diamond pn‐junctions.
993.
Geometric Formulation and Multi‐dark Soliton Solution to the Defocusing Complex Short Pulse Equation 下载免费PDF全文
In the present paper, we study the defocusing complex short pulse (CSP) equations both geometrically and algebraically. From the geometric point of view, we establish a link of the complex coupled dispersionless (CCD) system with the motion of space curves in Minkowski space , then with the defocusing CSP equation via a hodograph (reciprocal) transformation, the Lax pair is constructed naturally for the defocusing CSP equation. We also show that the CCD system of both the focusing and defocusing types can be derived from the fundamental forms of surfaces such that their curve flows are formulated. In the second part of the paper, we derive the defocusing CSP equation from the single‐component extended Kadomtsev‐Petviashvili (KP) hierarchy by the reduction method. As a by‐product, the N‐dark soliton solution for the defocusing CSP equation in the form of determinants for these equations is provided. 相似文献
994.
Hiroaki Kobayashi Yôtarô Nishio Ken Kanazawa Shinji Kuroda Masanori Mitome Yoshio Bando 《Physica B: Condensed Matter》2012,407(15):2947-2949
We have studied the structural properties of the phase separation in Zn1−xCrxTe films grown by MBE with a relatively high Cr composition x∼0.2. In the combined analyses using TEM and EELS, it has been revealed that the Cr-aggregated regions are composed of precipitates of the hexagonal structure, which are formed in a particular crystallographic relation with the zinc-blende (ZB) structure of the matrix that the c-plane of the hexagonal structure nearly parallel to the (1 1 1) plane of the ZB structure. In the XRD measurements, the diffraction from the hexagonal precipitates has been detected in the ω-scan. From the measurements on the series of films grown at different temperatures, it has been suggested the hexagonal precipitates were formed in a larger quantity with the increase in growth temperature. 相似文献
995.
Observation of temporal vector soliton propagation and collision in birefringent fiber 总被引:1,自引:0,他引:1
Rand D Glesk I Brès CS Nolan DA Chen X Koh J Fleischer JW Steiglitz K Prucnal PR 《Physical review letters》2007,98(5):053902
We report the experimental observation of temporal vector soliton propagation and collision in a linearly birefringent optical fiber. To the best of the authors' knowledge, this is both the first demonstration of temporal vector solitons with two mutually incoherent component fields, and of vector soliton collisions in a Kerr nonlinear medium. Collisions are characterized by an intensity redistribution between the two components, and the experimental results agree with numerical predictions of the coupled nonlinear Schr?dinger equation. 相似文献
996.
997.
998.
Motohiro Akazome Shusaku TomaTatsunori Horiguchi Ken MegumiShoji Matsumoto 《Tetrahedron》2011,67(16):2844-2848
Inclusion compounds of a dipeptide, (S)-threonyl-(S)-phenylglycine (Thr-Phg), with several aliphatic alcohols were easily prepared by grinding them in a mortar. Thr-Phg molecules arranged in antiparallel to construct a sheet, and guest alcohols were accommodated in a chiral pocket between the sheets. 3-Butyn-2-ol and 2-butanol were included with moderate enantioselectivity, 57% ee (R) and 49% ee (R), respectively. The role of the hydroxy group of Thr-Phg is not only to construct the unique pocket but also to capture guest alcohols by hydrogen bonding. 相似文献
999.
1000.
Shi Li Lishan Zhou Ken‐Ichiro Kanno Tamotsu Takahashi 《Journal of heterocyclic chemistry》2011,48(3):517-528
Metallacyclopentadiene, which is recognized as a metallo‐heterocycle, is an important intermediate for the formation of aromatic derivatives. In this short review, we summarized the recent advance on construction of axial, central, planar, and helical chirality by transition‐metal‐catalyzed aromatic compounds formation via metallacyclopentadienes. J. Heterocyclic Chem., (2011). 相似文献