Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Lower critical fields in an ellipsoid-shaped YBa[sub 2]Cu[sub 3]O[sub 6. 95] single crystal

Journal Article · · Physical Review, B: Condensed Matter; (United States)
; ; ;  [1];  [2]
  1. Department of Physics, University of British Columbia, Vancouver, British Columbia, V6T1Z1 (Canada)
  2. Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, L8S4M1 (Canada)
The lower critical fields of YBa[sub 2]Cu[sub 3]O[sub 6.95] have been determined by magnetization [ital M]([ital H]) measurements using an ellipsoidal-shaped crystal and a thin platelet for [bold H][parallel][ital c] and [bold H][perpendicular][ital c], respectively. Careful data analysis rules out the effects of surface barriers. The data show a linear temperature dependence of [ital H][sub [ital c]1] below about 0.5[ital T][sub [ital c]], with [ital H][sub [ital c]1](0)=1100 Oe and 200 Oe for [bold H][parallel][ital c] and [bold H][perpendicular][ital c], respectively. The anisotropy factor [gamma] is almost temperature independent and has the value 5.6[plus minus]0.3. By comparison of the [ital H][sub [ital c]1] data to results of London penetration-depth measurements, the vortex core energy is found to be linear with temperature.
OSTI ID:
6669417
Journal Information:
Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 50:6; ISSN PRBMDO; ISSN 0163-1829
Country of Publication:
United States
Language:
English