Surface-barrier effects in grain-aligned HgBa{sub 2}CuO{sub 4+{delta}}, HgBa{sub 2}CaCu{sub 2}O{sub 6+{delta}}, and HgBa{sub 2}Ca{sub 2}Cu{sub 3}O{sub 8+{delta}} compounds
- Science and Technology Center for Superconductivity, Urbana, Illinois 61801 (United States)
- Department of Physics, University of North Dakota, Grand Forks, North Dakota 58202 (United States)
We have studied the magnetic hysteresis and relaxation processes of grain-aligned HgBa{sub 2}CuO{sub 4+{delta}}, HgBa{sub 2}CaCu{sub 2}O{sub 6+{delta}}, and HgBa{sub 2}Ca{sub 2}Cu{sub 3}O{sub 8+{delta}} compounds. The penetration field, {ital H}{sub {ital p}}, the width of the magnetization loops, {Delta}{ital M}, and the irreversibility field, {ital H}{sub irr}, of each compound were found to exhibit an exponential temperature dependence [i.e., {ital H}{sub {ital p}}, {ital H}{sub irr}, {Delta}{ital M}{proportional_to}exp({minus}{ital cT}/{ital T}{sub 0})]. This suggests that their magnetic relaxation is controlled by the penetration of two-dimensional pancake vortices over the Bean-Livingston surface barrier.
- Research Organization:
- Univ. of Illinois at Urbana-Champaign, IL (United States)
- DOE Contract Number:
- FG02-91ER45439
- OSTI ID:
- 90488
- Journal Information:
- Physical Review, B: Condensed Matter, Vol. 52, Issue 6; Other Information: PBD: 1 Aug 1995
- Country of Publication:
- United States
- Language:
- English
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