Experimental evidence for a multicritical point in the magnetic phase diagram for the mixed state of clean untwinned YBa2Cu3O7
Ημερομηνία
1993Συγγραφέας
Safar, H.Gammel, P. L.
Huse, D. A.
Bishop, D. J.
Lee, W. C.
Giapintzakis, John
Ginsberg, D. M.
Source
Physical Review LettersVolume
70Pages
3800-3803Google Scholar check
Metadata
Εμφάνιση πλήρους εγγραφήςΕπιτομή
We report on transport measurements in fields up to 16 T in clean, untwinned single crystals of YBa2Cu3O7 which indicate that there is a critical end point for first-order melting in the H-T phase diagram in the mixed state of that system. Our data show that at a well defined value of the magnetic field, the phase boundary sharply changes slope where the first-order melting transition gives way to a second-order vortex-glass transition. These data suggest that the recently observed first-order transition is robust in the presence of a finite amount of disorder and that the vortex-glass transition only occurs for disorder beyond a certain critical amount. © 1993 The American Physical Society.