Abstract
We report voltage noise studies in the superconducting transition of thin Tin (Sn) films. Voltage noises are measured as a function of temperature and ac current. The noise spectral power S 1/2 strongly depends on the temperature and current, with the peak temperature in S 1/2 shifted down from that of dR/dT. Comparison with the dc noise measurement shows the S 1/2 is much larger with ac current than dc. I-V characteristics and voltage noises are measured simultaneously to reveal the nature of the excess noises. The noise dependence on voltage strongly suggests the nature of vortex shot noise with a characteristic √V dependence for small V and reduction of S 1/2 due to strong correlation of vortices at large V.
Original language | English (US) |
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Pages (from-to) | 206-210 |
Number of pages | 5 |
Journal | Journal of Low Temperature Physics |
Volume | 151 |
Issue number | 1-2 PART 1 |
DOIs | |
State | Published - Apr 2008 |
Keywords
- Superconducting transition
- Voltage noises
- Vortex motion
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Materials Science(all)
- Condensed Matter Physics