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

Resistive transition curves in magnetic fields for Tl sub 2 Ba sub 2 Ca sub n minus 1 Cu sub n O sub y ( n =1, 2, 4) compounds: Dependence on the number of Cu-O layers

Journal Article · · Physical Review, B: Condensed Matter; (USA)
; ;  [1]; ; ;  [2]
  1. Sanyo Tsukuba Research Center, 2-1 Koyadai, Tsukuba, Ibaraki 305 (Japan)
  2. National Research Institute for Metals, Tsukuba Laboratories, 1-2-1, Sengen, Tsukuba, Ibaraki (Japan)
A systematic measurement of the superconducting resistive transition curves in magnetic fields has been performed for Tl{sub 2}Ba{sub 2}Ca{sub {ital n}{minus}1}Cu{sub {ital n}}O{sub {ital y}} ({ital n}=1, 2, 4) compounds. It is found that the broadening of the transition curves varies systematically with the number of Cu-O layers (i.e., the value {ital n}). The slope of the field-versus-temperature curves in fields parallel to the {ital c} plane increases with decreasing {ital n}, while the slope in perpendicular fields is almost independent of {ital n}. This result suggests that the upper critical fields and the coherence lengths of these compounds have a strong correlation with {ital n}. It is concluded that the coherence length along the {ital c} axis of Tl{sub 2}Ba{sub 2}CuO{sub {ital y}} is smaller than the thickness of the Tl-O-layer region. According to the Josephson-coupled layer model, Tl{sub 2}Ba{sub 2}CuO{sub {ital y}} is expected to be a two-dimensional superconductor.
OSTI ID:
6436998
Journal Information:
Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 42:4; ISSN 0163-1829; ISSN PRBMD
Country of Publication:
United States
Language:
English