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91.
Nadal F Argoul F Kestener P Pouligny B Ybert C Ajdari A 《The European physical journal. E, Soft matter》2002,9(4):387-399
We report a theoretical and experimental study of the hydrodynamic flow induced by an a.c. electric field in the vicinity
of a dielectric stripe deposited on a conducting plate. In the theoretical part, we model the stripe as a small change of
the surface capacitance of the plate, and a perturbative approach is used to perform the calculations. This approach predicts
an outwards rectified electro-osmotic slip along the surface that generates two steady counter-rotating rolls, the size of
which decreases with the frequency. In the experimental section, we use tracers to determine the structure of the flow and
investigate its dependence on the frequency and the amplitude of the applied voltage. The structure and amplitude of the observed
flow compares satisfactorily with the theoretical analysis. This could guide the design of surface-controlled flows and help
to understand the collective behavior of colloids near electrodes.
Received 20 June 2002
RID="a"
ID="a"e-mail: nadal@crpp.u-bordeaux.fr 相似文献
92.
We propose a simple scheme to generate two-mode entangled coherent state in two separated cavities and realize the entanglement
reciprocation between the superconducting charge qubits and continuous-variable system. By measuring the state of charge qubits,
we find that the entanglement of two charge qubits, which are initially prepared in the maximally entangled state, can be
transferred to the two-cavity field, and at this time the two-cavity field is in the entangled coherent state. We also find
that the entanglement can be retrieved back to the two charge qubits after measuring the state of the two-cavity field.
相似文献
93.
THILO GIPSER HUBERT A. JAGER LUTZ RAPP Swiss Federal Institute of Technology Communication Technology Laboratory ETH Zentrum Zurich Switzerland 《Fiber and Integrated Optics》1998,17(1):21-40
All-optical networks are a sound answer to the huge data traffic demand expected for the forthcoming information society. Interesting networking aspects are the broadcasting, scalability, and reconfiguration in an all-optical environment. These issues are addressed in the present article for an all-optical network called MATRIX, which is time slotted and uses packet switching. The architecture enables the all-optical interconnection of a large number of nodes with both a small number of wavelengths and wavelength continuity based on a consequent exploitation of wavelength-division multiplexing and space-division multiplexing (i.e., multiple fibers per cable are used). For an efficient use of the resources, each node is equipped with multiple transmitters and receivers, respectively. Two different broadcasting schemes are investigated. An analytical model is developed, and the corresponding simulation results are in good agreement. It is further shown how different networks of arbitrary size can be interconnected to larger all-optical network clusters, thereby providing scalability not only with respect to the number of nodes but also to the geographical extension. Finally, wavelength reassignments allow change of optical paths through the network in case of changing traffic patterns or network failures in order to best exploit the available network resources. The total number of possible configurations is determined by the theory of Latin Squares. 相似文献
94.
A new thin-film electro-optic switch employing two stable states of polarization is proposed and investigated. The design can be further employed to realize a TE-TM polarization converter by constructing a Mach-Zehnder type interferometer integrated optical switch. The limitations and design procedures for electro-optic devices are also discussed. 相似文献
95.
A review of physical principles of design as well as some ways of technical realization of controlled resonance semiconductor devices at millimeter and submillimeter wavelengths is presented. The operation of such devices is based on cyclotron and magnetoplasma resonances as well as on Fabry-Perot resonance. Such choice has been made due to the fact that these resonance phenomena are the most typical ones for the magnetized semiconductor plasma. 相似文献
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