Results 161 to 170 of about 519,355 (198)

SUPERCONDUCTIVITY WITH SHORT COHERENCE LENGTH

International Journal of Modern Physics B, 2007
Exploiting the shortness of the coherence length in many of the recently discovered superconductors, we propose a new formulation to evaluate the superconducting transition temperature Tc. Its tentative application to the Hubbard-Holstein model suggests the appearance of very high Tc in a reasonable range of parameters involved in the model.
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Biaxial coherence length in a nematic π-cell

The European Physical Journal E, 2013
In a highly frustrated calamitic nematic phase, the strain can be relaxed by lowering the nematic order: the starting uniaxial symmetry can be broken and it can be replaced locally with transient biaxial domains. Using simple optical retardation measurements, we estimate the length scale over which the biaxial disturbance decays in space within a π ...
R. Hamdi, G. Lombardo, MP de Santo, BARBERI, Riccardo Cristoforo   +3 more
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Pairing-bag excitations in small-coherence-length superconductors

Physical Review Letters, 1988
Localized baglike solutions in the pairing theory of superconductivity are studied. Starting from the Bogoliubov--de Gennes equations on a two-dimensional square lattice for half-filled negative-U Hubbard model, cigar- and star-shaped bags are numerically obtained, inside of which the order parameter is reduced, self-consistently trapping an added ...
, Bishop, , Lomdahl, , Schrieffer, , Trugman   +3 more
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Pippard-coherence-length tensor for anisotropic superconductors

Physical Review B, 1988
In the framework of a generalized fully anisotropic Bardeen-Cooper-Schrieffer-type quantum theory, the low-temperature, low-field coherence-length tensor is derived from first principles. Anisotropy of the Fermi surface, the gap parameter, and the energy band structure in the effective-mass approximation is included.
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A coherence length for matter waves

Conference Digest. 2000 International Quantum Electronics Conference (Cat. No.00TH8504), 2005
We introduce the concept and mathematical description of a coherence length and a coherence momentum for matter states, and explain their significance via the example of the motional states of a single cold trapped ion. These parameters describe the coherence properties of matter waves analogously to the way in which optical coherence determines the ...
S. Franke-Arnold, S.M. Barnett, G. Huyet
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Holographic Coherence Length of a Pulse Laser

Applied Optics, 1971
A theoretical treatment of holographic brightness for a gaussian-shaped laser pulse permits a more rigorous consideration of holographic coherence length for single-mode (TEM(00q)) pulse laser. Three cases are treated: (1) the ideal single frequency pulse laser oscillator; (2) the pulse laser oscillator with frequency sweep; and (3) the pulse laser ...
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Transverse coherence lengths, processing limits and implications.

The Journal of the Acoustical Society of America, 2009
How does scattering in sound channels (deep and shallow waters) limit coherent array processing or what is the limitation of resolution in terms of the mutual coherence function and its temporal and spatial coherence lengths? The resolution of an array is limited by the mutual coherence function; but estimation in a partially coherent noise background ...
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Neutron interactions and coherent scattering lengths

2000
Abstract Scattering lengths are the relevant quantities for the description of the neutron-nuclear interaction at low energies and they are of substantial interest for the understanding of the basic nucleon-nucleon interaction. Related investigations are directly connected to the elementary hadron-hadron interactions, namely neutron ...
Helmut Rauch, Samuel A Werner
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Determination of Coherence Length from Directionality

1978
In this contribution we shall present a method for obtaining the coherence conditions on a planar, quasi-monochromatic, possibly virtual, source from the angular distribution of its emission. The result is obtained by assuming a special functional dependence of the cross-spectral density function [cf. Eq. (2.13)].
H. A. Ferwerda, M. G. van Heel
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Blending Donors with Different Molecular Weights: An Efficient Strategy to Resolve the Conflict between Coherence Length and Intermixed Phase in Polymer/Nonfullerene Solar Cells

Small, 2022
Qiuju Liang, Zicheng Ding, Kui Zhao
exaly