Experimental determination of the symmetry of the superconducting pairing state in yttrium barium copper oxide
Wollman, David Anders
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/20693
Description
Title
Experimental determination of the symmetry of the superconducting pairing state in yttrium barium copper oxide
Author(s)
Wollman, David Anders
Issue Date
1996
Doctoral Committee Chair(s)
Greene, Laura H.
Department of Study
Physics
Discipline
Physics
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Physics, Condensed Matter
Language
eng
Abstract
In this thesis I present measurements of bimetallic Pb-Au-YBCO dc SQUIDs (Superconducting QUantum Interference Devices) and Josephson junctions that provide an important clue to the origin of the pairing mechanism for high temperature superconductivity in the cuprates. By probing the momentum space anisotropy of the phase of the superconducting order parameter, we can experimentally determine the symmetry of the superconducting pairing state in YBCO and distinguish between the leading candidate states that have been proposed. We find that the superconducting order parameter in YBCO changes sign between orthogonal directions in momentum space, unlike the isotropic order parameter in conventional superconductors. The sign change of the order parameter is consistent with a $d\sb{x\sp2-y\sp2}$ pairing state symmetry.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.