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71.
We develop a theory of extrinsic spin currents in semiconductors, resulting from spin-orbit coupling at charged scatterers, which leads to skew-scattering and side-jump contributions to the spin-Hall conductivity. Applying the theory to bulk n-GaAs, without any free parameters, we find spin currents that are in reasonable agreement with experiments by Kato et al. [Science 306, 1910 (2004)]. 相似文献
72.
We analyze the frequency-dependent noise of a current through a quantum dot which is coupled to Fermi leads and which is in the Coulomb blockade regime. We show that the asymmetric shot noise, as a function of detection frequency, shows steps and becomes super-Poissonian. This provides experimental access to the quantum fluctuations of the current. We present an exact calculation of the noise for a single dot level and a perturbative evaluation of the noise in Born approximation (sequential tunneling regime but without Markov approximation) for the general case of many levels with charging interaction. 相似文献
73.
Difference Fourier transforms for nonreduced root systems 总被引:1,自引:0,他引:1
In the first part of the paper kernels are constructed which
meromorphically extend the Macdonald-Koornwinder polynomials in their degrees.
In the second part the kernels associated with
rank one root systems are used to define nonsymmetric variants of the
spherical Fourier transform on the quantum SU(1,1) group.
Related Plancherel and inversion formulas are derived using double
affine Hecke algebra techniques. 相似文献
74.
Valentina?CasarinoEmail author Klaus-Jochen?Engel Rainer?Nagel Gregor?Nickel 《Integral Equations and Operator Theory》2003,47(3):289-306
In this paper we convert a (linear abstract) initial boundary value
problem into an abstract Cauchy problem on some product space and use
semigroup methods to solve it. In particular, we apply spectral theory in
order to discuss stability under boundary feedback. 相似文献
75.
Jasper V. Stokman 《Transactions of the American Mathematical Society》2000,352(4):1527-1579
The five parameter family of Koornwinder's multivariable analogues of the Askey-Wilson polynomials is studied with four parameters generically complex. The Koornwinder polynomials form an orthogonal system with respect to an explicit (in general complex) measure. A partly discrete orthogonality measure is obtained by shifting the contour to the torus while picking up residues. A parameter domain is given for which the partly discrete orthogonality measure is positive. The orthogonality relations and norm evaluations for multivariable -Racah polynomials and multivariable big and little -Jacobi polynomials are proved by taking suitable limits in the orthogonality relations for the Koornwinder polynomials. In particular new proofs of several well-known -analogues of the Selberg integral are obtained.
76.
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79.
Engel T. G. Veracka M. J. Neri J. M. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2010,38(2):194-198
80.