Hall effect in untwinned single-crystal superconducting YBa2Cu307-y
Rice, Joseph Paul
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/2142/18885
Description
Title
Hall effect in untwinned single-crystal superconducting YBa2Cu307-y
Author(s)
Rice, Joseph Paul
Issue Date
1992
Doctoral Committee Chair(s)
Ginsberg, D.M.
Department of Study
Physics
Discipline
Physics
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Hall Effect
single-crystal
superconductor
untwinned domains
fluctuation
Hall coefficient
Language
en
Abstract
We measured the Hall effect in untwinned single-crystal
YBa2Cu3o7_Y, a high-Tc superconductor. The crystals were grown
using a technique that we invented, in which untwinned domains
are produced naturally without applying stress to the sample.
The Hall effect measurements were directed at understanding
fluctuation phenomena just above Tc, where small regions of a
sample experience short-lived thermodynamic fluctuations into the
superconducting state. Effects from these fluctuations appear in
the temperature dependences of the Hall coefficient and
conductivity as substantial deviations from the 1/T normal-state
behavior. Because the original Fukuyama, Ebisawa, and Tsuzuki
theory of the fluctuation-induced Hall effect is for an isotropic
superconductor and YBa2Cu3o7_Y is a layered material, we compared
our data to an extended version. We calculated terms that were
lacking and corrected mistakes in the literature to arrive at a
complete and consistent theory for the effect of fluctuations on
the Hall effect in a layered superconductor. From the fits of
this theory to our data we were able to obtain fundamental
information, such as the size of the superconducting coherence
length and the nature of the coupling of the superconducting
planes within the crystal structure of YBa2Cu307 _y•
Below Tc, we obtained information about vortex motion from
the Hall effect and magnetoresistance. For example, we found
that the Hall resistivity changes sign over a certain range of
magnetic field and temperature below Tc, even in untwinned
crystals. Thus this anomalous behavior, originally discovered in
twinned samples, is not due to effects of twin planes.
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.
