Title :
Transitions in the vortex lattice of YBa2Cu3O 7
Author :
Hucho, C. ; Levy, M.
Author_Institution :
Dept. of Phys., Wisconsin Univ., Milwaukee, WI, USA
Abstract :
We present ultrasonic experiments on the elastic behavior of the magnetic vortex-system in YBCO. After a brief review of the influence of pinning-sites on the H-T phase diagram, results from a recently developed low frequency acoustic experiment, a sampled continuous wave technique on a twin-free YBCO single crystal, are presented. This technique is related to vibrating reed experiments, but has the advantage of constant angle between sample and applied magnetic field, thereby keeping the flux density inside the sample unaltered. It is related to ac-resistivity measurements as well, because the interaction between the driving sound-wave and the vortices is mediated by the sound-induced motion of charge carriers, but it operates at much lower current densities
Keywords :
barium compounds; flux pinning; flux-line lattice; high-temperature superconductors; ultrasonic absorption; yttrium compounds; 3 MHz; H-T phase diagram; US attenuation; YBa2Cu3O7; ac-resistivity measurements; constant angle; driving sound-wave vortex interaction; elastic behavior; low frequency acoustic experiment; magnetic vortex-system; pinning-sites; sampled continuous wave technique; sound-induced charge carrier motion; ultrasonic experiments; vibrating reed experiments; vortex lattice transitions; Acoustic measurements; Acoustic waves; Current measurement; Density measurement; Frequency; Lattices; Magnetic field measurement; Magnetic flux; Magnetoelasticity; Yttrium barium copper oxide;
Conference_Titel :
Ultrasonics Symposium, 1996. Proceedings., 1996 IEEE
Conference_Location :
San Antonio, TX
Print_ISBN :
0-7803-3615-1
DOI :
10.1109/ULTSYM.1996.584017
