Magnetization of underdoped YBa2Cu3Oy above the irreversibility field

Scientific paper - Original scientific paper

• Author: Jing Fei Yu
• Author: B. J. Ramshaw
• Author: Ivan Kokanović
• Author: K. A. Modic
• Author: N. Harrison
• Author: James Day
• Author: Ruixing Liang
• Author: W. N. Hardy
• Author: D. A. Bonn
• Author: A. McCollam
• Author: S. R. Julian
• Author: J. R. Cooper
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

Torque magnetization measurements on YBa2Cu3Oy (YBCO) at doping y = 6.67 (p = 0.12), in dc fields (B) up to 33 T and temperatures down to 4.5 K, show that weak diamagnetism persists above the extrapolated irreversibility field Hirr(T = 0) ≈ 24 T. The differential susceptibility dM/dB, however, is more rapidly suppressed for B 16 T than expected from the properties of the low field superconducting state, and saturates at a low value for fields B 24 T. In addition, torque measurements on a p = 0.11 YBCO crystal in pulsed field up to 65 T and temperatures down to 8 K show similar behavior, with no additional features at higher fields. We offer two candidate scenarios to explain these observations: (a) superconductivity survives but is heavily suppressed at high field by competition with charge-density-wave (CDW) order; (b) static superconductivity disappears near 24 T and is followed by a region of fluctuating superconductivity, which causes dM/dB to saturate at high field. The diamagnetic signal observed above 50 T for the p = 0.11 crystal at 40 K and below may be caused by changes in the normal state susceptibility rather than bulk or fluctuating superconductivity. There will be orbital (Landau) diamagnetism from electron pockets and possibly a reduction in spin susceptibility caused by the stronger three-dimensional ordered CDW.

• Keywords (english): superconductivity; superconducting fluctuations; charge-density-wave
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Physical review B: Condensed matter and materials physics
• Numbering: vol. 92, no. 18, 180509(R)
• p-ISSN: 1098-0121
• e-ISSN: 1550-235X
• DOI: https://doi.org/10.1103/PhysRevB.92.180509
• URN:NBN: urn:nbn:hr:217:010213
• Publication: 2015
• Project: Number: IP-2013-11-6216; Title (croatian): Transporna, magnetska i termodinamička svojstva odabranih anorganskih i organskih materijala; Acronym: TRANMAGTHERPROMAT; Leader: Ivan Kokanović; Jurisdiction: Croatia; Funding stream: IP
• Document URL: https://journals.aps.org/prb/abstract/10.1103/PhysRevB.92.180509
• Type of resource: Text
• Access conditions: Open access
• Public note: Copyright (2015) by the American Physical Society. Received 18 September 2015; revised manuscript received 1 November 2015; published 23 November 2015.
• Created on: 2020-01-23 16:20:26