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تسجيل مستخدم جديدThermoelectric effect in superconducting nanostructures
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We study thermoelectric effects in superconducting nanobridges and demonstrate that the magnitude of these effects can be comparable or even larger than that for a macroscopic superconducting circuit. The reason is related to a possibility to have very large gradients of electron temperature within the nanobridge. The corresponding heat conductivity problems are considered. It is shown that the nanoscale devices allow one to get rid of masking effects related to spurious magnetic fields.
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We demonstrate that thermoelectric currents in superconducting bilayers with a spin-active interface are controlled by the two competing processes. On one hand, spin-sensitive quasiparticle scattering at such interface generates electron-hole imbalan
ce and yields orders-of-magnitude enhancement of the thermoelectric effect in the system. On the other hand, this electron-hole imbalance gets suppressed in the superconductor bulk due to electron scattering on non-magnetic impurities. As a result, large thermoelectric currents can only flow in the vicinity of the spin-active interface and decay away from this interface at a distance exceeding the electron elastic mean free path $ell$. The magnitude of the thermoelectric effect reaches its maximum provided $ell$ becomes of order of the total bilayer thickness.
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