2007/03/24 by Y. Jia, Yun‐Fang Jia, Jia, Y. +23
Physics and Astronomy · #Condensed matter physics #Dissipation #FOS: Physical sciences #Magnetic field #Mechanics #Physics #Physics of Superconductivity and Magnetism #Quantum Hall effect #Quantum mechanics #Quantum tunnelling #Quasiparticle #Resistive touchscreen #Superconductivity #Superconductivity (cond-mat.supr-con) #Superconductivity in MgB2 and Alloys #Vortex #Vortex state #Zero-point energy #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.cond-mat/0703637
published in arXiv (Cornell University) (Cornell University) · 4 pages, 5 figures
arxiv created 2007/03/24 · openalex publication_date 2007/03/24 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We have studied mixed-state dissipation in epitaxial MgB2 thin films by measurements of resistive transition, current-voltage characteristics, Hall effect, and point-contact tunnelling spectrum. We found that unlike single gap superconductors with negligible vortex quantum fluctuations in which vortices are frozen at T=0 K, finite zero-temperature dissipation due to vortex motion exists in MgB2 over a wide magnetic field range. This dissipation was found to be associated with proliferation of quasiparticles from the π-band of MgB2. The result shows that the vortex fluctuations are enhanced by two-band superconductivity in MgB2 and we suggest that the vortex quantum fluctuation is a possible cause of the non-vanishing zero-temperature dissipation.