85 research outputs found
Quantum oscillations of rectified dc voltage as a function of magnetic field in an "almost" symmetric superconducting ring
Periodic quantum oscillations of a rectified dc voltage Vdc(B) vs the
perpendicular magnetic field B were measured near the critical temperature Tc
in a single superconducting aluminum almost symmetric ring (without specially
created circular asymmetry) biased by alternating current with a zero dc
component. With varying bias current and temperature, these Vdc(B) oscillations
behave like the Vdc(B) oscillations observed in a circular-asymmetric ring but
are of smaller amplitude. The Fourier spectra of the Vdc(B) functions exhibit a
fundamental frequency, corresponding to the ring area, and its higher
harmonics. Unexpectedly, satellite frequencies depending on the structure
geometry and external parameters were found next to the fundamental frequency
and around its higher harmonics.Comment: author english version, 2 pages, 3 figires, Proc. of the XXXIV
Conference on Low-Temperature Physics "NT-34" (Russia, 2006
Quantum Oscillations of the Critical Current of Asymmetric Aluminum Loops in Magnetic Field
The periodical dependencies in magnetic field of the asymmetry of the
current-voltage curves of asymmetric aluminum loop are investigated
experimentally at different temperatures below the transition into the
superconducting state T < Tc. The obtained periodical dependencies of the
critical current on magnetic field allow to explain the quantum oscillations of
the dc voltage as consequence of the rectification of the external ac current
and to calculate the persistent current at different values of magnetic flux
inside the loop and temperatures.Comment: 2 pages, 2 figures, will be published in the Proceedings of the 24th
International Conference on Low Temperature Physic
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