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排序方式: 共有97条查询结果,搜索用时 15 毫秒
1.
A 1.3 ?m laser in a compact disc package is coupled to single-mode fibre using two graded-index lenses in a nearly confocal scheme. An increase in the alignment tolerance at the lens-lens interface by a factor of six suggests the design for a potentially very low-cost connectorised laser package. The coupling efficiency of approx. 6% (?12 dB) is shown to be adequate for local loop applications. 相似文献
2.
In this article we present our recent efforts in designing a comprehensive consistent scientific workflow, nicknamed Wolf2 Pack, for force-field optimization in the field of computational chemistry. Atomistic force fields represent a multiscale bridge that connects high-resolution quantum mechanics knowledge to coarser molecular mechanics-based models. Force-field optimization has so far been a time-consuming and error-prone process, and is a topic where the use of a scientific workflow can provide obvious great benefits. As a case study we generate a gas-phase force field for methanol using Wolf2 Pack, with special attention given toward deriving partial atomic charges. 相似文献
3.
Robert Burger Patrick Reith Victor Akujobi Jens Ducrée 《Microfluidics and nanofluidics》2012,13(4):675-681
This work presents a novel magnetic actuation scheme for advanced particle handling on our previously introduced, centrifugal microfluidic platform for array-based analysis of individual cells and beads. The conceptually simple actuation is based on the reciprocating motion of an elastomeric membrane featuring an integrated permanent magnet and a stationary magnet aligned along the orbit of a disc-based chamber. This compression chamber is placed at the downstream end of the particle capture chamber to induce centripetally directed, hydrodynamic lift forces on particles trapped in V-shaped geometrical barriers. Towards high frequencies of rotation, the on-disc magnet ceases to follow the rapidly oscillating magnetic field, so that the magnetic actuator is disabled during the initial, sedimentation-based filling of the trap array. At reduced spin speeds, the residence time of the magnetic actuator is sufficient to displace the magnetic actuator, resulting in a flow through the V-cup array that re-distributes, and eventually fully depletes, the previously trapped beads from the array. The same magnetic deflection scheme is also demonstrated to accelerate mixing, e.g. for upstream sample preparation. 相似文献
4.
We present results of a systematic growth study on the substrate temperature-driven de-wetting of CeIn3 thin films as a reference compound for the heavy-fermion superconductor CeCoIn5. This study is motivated by the last results on the improved surface morphology and in-plane orientation preference of c-axis oriented CeCoIn5 thin films. In apparently phase pure CeIn3 thin films, as far as x-ray diffraction can tell, we find evidence for minor In segregation by means of percolating resistance contributions of In in the films. We argue that further efforts into improving the films' morphology towards optimized surfaces for the preparation of macroscopic planar tunnel junctions may be futile. As an alternative approach, we present results of electronic transport measurements on CeIn3 and CeCoIn5 microcrystals isolated from the thin films by means of focused particle beam induced processing, such as focused ion beam milling and deposition. 相似文献
5.
A multicasting photonic space switch reconfigurable in 50 ns is demonstrated utilising commercially available acousto-optic Bragg cells at lambda =0.83 mu m. Insertion loss of 15 dB, extinction ratio of 33 dB, crosstalk of -24 dB and polarisation difference of 0.8 dB are reported.<> 相似文献
6.
F. Völklein H. Reith M. C. Schmitt M. Huth M. Rauber R. Neumann 《Journal of Electronic Materials》2010,39(9):1950-1956
This paper focuses on the determination of thermal and electrical properties of individual thermoelectric nanowires, primarily
bismuth and bismuth compound nanowires, as functions of their crystallinity, diameter, and composition. For measurements of
the Seebeck coefficient and the electrical and thermal conductivity, specially designed microchips have been developed and
employed. Finite-element simulations demonstrate that the temperature profiles of the microchips provide suitable temperature
gradients for Seebeck-effect measurements and heat-sink conditions for thermal conductivity investigations. First measurements
of thermal conductivity of metallic nanowires and of Seebeck coefficients of granular nanowires prepared by focused electron-beam-induced
deposition are presented. Some of these results are discussed in the framework of finite-size-effect theory. 相似文献
7.
An electroplating technique for permanently fixing single-mode fibers into position in optical device packages is described. In this technique, the fiber is mounted in a metal tube and aligned to an optical device mounted on a metal substrate. The fiber is in close proximity to the substrate and a flexible conductive gel is used to connect the two electrically. The fiber, gel, and substrate thus form the plating cathode. When immersed in a plating bath with an anode inserted, metal can be deposited across the gel, forming a strong metal bridge between the fiber and substrate, locking the fiber into position. Under appropriate conditions, misalignments within ±1 μm during the plating process have been observed. This technique was used to package a laser diode transmitter, which locked the laser-to-fiber alignment to within 0.7 μm, or 0.1 dB of the optimum coupled power 相似文献
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