UPPER THRESHOLD FIELDS OF DENDRITIC FLUX JUMPS IN GOLD-COATED MgB2 THIN FILMS

Autor:	D. V. Shantsev, Moo-Hyun Cho, V. V. Yurchenko, Hyeong-Jin Kim, Eun-Mi Choi, Jae Yeap Lee, Sung-Ik Lee, Å. A. F. Olsen, Tom H. Johansen, Hyun-Sook Lee
Rok vydání:	2007
Předmět:	Superconductivity Range (particle radiation) Materials science Field (physics) Condensed matter physics business.industry Flux Statistical and Nonlinear Physics Condensed Matter Physics Magnetic hysteresis Optics Condensed Matter::Superconductivity Thermal Thin film business Noise (radio)
Zdroj:	International Journal of Modern Physics B. 21:3310-3313
ISSN:	1793-6578 0217-9792
DOI:	10.1142/s0217979207044433
Popis:	We measured the magneto-optical images (MOIs) and the magnetic hysteresis (M – H) curves of c-axis-oriented MgB 2 thin films to investigate the flux penetration in the form of dendritic avalanches. In order to understand the role of the thermal effects, we prepared Au -coated MgB 2 thin films with different thicknesses of gold. While the MOI provides a spatially resolved flux pattern, the M – H curve presents global and average information about the flux noise associated with avalanches. These two types of measurements complement each other. The upper threshold field, above which the flux noise disappears, was determined from the M-H curves while the lower threshold field was determined from both the M – H curves and the MO images. The field range where the flux penetrates via avalanches is found to be smaller for thicker gold layers. These results are important for many superconducting applications.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::e2f12bb12ffece00723b1b15c1438164 https://doi.org/10.1142/s0217979207044433 Zobrazit plný text záznamu