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تسجيل مستخدم جديدEquilibrium properties of mesoscopic quantum conductors
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Review article on equilibrium properties of mesoscopic quantum conductors.
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A theory of non-equilibrium (``shot) noise and high frequency conductance in diffusive mesoscopic conductors with screening is presented. Detailed results are obtained for two simple geometries, for both large and short electron-electron scattering l
ength $l_{ee}$, at frequencies of the order of the inverse Thouless time $1/tau_T$. The conductance and the noise are found to exhibit significant frequency dependence. For $L ll l_{ee}$, the high-frequency ($omegatau_T gg 1$) shot noise spectral density $S_I(omega)$ approaches a finite value between $2eI/3$ and $2eI$, depending on the screening properties of the system, with temperature corrections to $S_I(omega)$ being linear in $T$. However, when $L gg l_{ee}$, $S_I(omega)$ grows as $omega^{1/4}$ (at T=0), is not upper-bound by $2eI$, and has a temperature-dependent component quadratic in $T$. As a result, measurements of $S_I(omega, T)$ can be utilized as a probe of the strength of electron-electron scattering.
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A dilute concentration of magnetic impurities can dramatically affect the transport properties of an otherwise pure metal. This phenomenon, known as the Kondo effect, originates from the interactions of individual magnetic impurities with the conduct
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