SANS investigations of the flux line lattice in unconventional superconductors
Small-angle neutron scattering has been used to study the flux line lattice (FLL) in the \(d\)-wave superconductors YBa\(_2\)Cu\(_3\)O\(_7\) and CeCoIn\(_5\). Our studies on the High-\(T_c\) superconductor YBa\(_2\)Cu\(_3\)O\(_7\) were carried out using a twin-free sample, and we present the first o...
Main Author: | |
---|---|
Published: |
University of Birmingham
2009
|
Subjects: | |
Online Access: | https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.514083 |
id |
ndltd-bl.uk-oai-ethos.bl.uk-514083 |
---|---|
record_format |
oai_dc |
spelling |
ndltd-bl.uk-oai-ethos.bl.uk-5140832019-04-03T06:39:45ZSANS investigations of the flux line lattice in unconventional superconductorsWhite, Jonathan Stuart2009Small-angle neutron scattering has been used to study the flux line lattice (FLL) in the \(d\)-wave superconductors YBa\(_2\)Cu\(_3\)O\(_7\) and CeCoIn\(_5\). Our studies on the High-\(T_c\) superconductor YBa\(_2\)Cu\(_3\)O\(_7\) were carried out using a twin-free sample, and we present the first observations of the intrinsic FLL structure in this material, with a magnetic field applied parallel to the crystal c-axis (H || c). We observe a sequence of field-driven FLL structure transitions, the detailed physics of which can be broadly described in terms of field-induced non-locality, the potency of which is perhaps increased by the anisotropy of the order-parameter. The heavy-fermion superconductor CeCoIn\(_5\) exhibits an exotic ground state that combines unconventional superconductivity with strong paramagnetism. With H || c, these properties contribute towards both a rich FLL structure phase diagram, and new behaviour of the FLL form factor. Most notably, we observe the form factor to increase with field, in strong contrast to the monotonic decrease expected from predictions made using more conventional theories. These results can be qualitatively described by calculations made within the framework of the quasiclassical Eilenberger theory, which indicate the increase in the form factor as due to field-induced Pauli paramagnetic effects which manifest most strongly within the flux line cores.537.623QC PhysicsUniversity of Birminghamhttps://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.514083http://etheses.bham.ac.uk//id/eprint/319/Electronic Thesis or Dissertation |
collection |
NDLTD |
sources |
NDLTD |
topic |
537.623 QC Physics |
spellingShingle |
537.623 QC Physics White, Jonathan Stuart SANS investigations of the flux line lattice in unconventional superconductors |
description |
Small-angle neutron scattering has been used to study the flux line lattice (FLL) in the \(d\)-wave superconductors YBa\(_2\)Cu\(_3\)O\(_7\) and CeCoIn\(_5\). Our studies on the High-\(T_c\) superconductor YBa\(_2\)Cu\(_3\)O\(_7\) were carried out using a twin-free sample, and we present the first observations of the intrinsic FLL structure in this material, with a magnetic field applied parallel to the crystal c-axis (H || c). We observe a sequence of field-driven FLL structure transitions, the detailed physics of which can be broadly described in terms of field-induced non-locality, the potency of which is perhaps increased by the anisotropy of the order-parameter. The heavy-fermion superconductor CeCoIn\(_5\) exhibits an exotic ground state that combines unconventional superconductivity with strong paramagnetism. With H || c, these properties contribute towards both a rich FLL structure phase diagram, and new behaviour of the FLL form factor. Most notably, we observe the form factor to increase with field, in strong contrast to the monotonic decrease expected from predictions made using more conventional theories. These results can be qualitatively described by calculations made within the framework of the quasiclassical Eilenberger theory, which indicate the increase in the form factor as due to field-induced Pauli paramagnetic effects which manifest most strongly within the flux line cores. |
author |
White, Jonathan Stuart |
author_facet |
White, Jonathan Stuart |
author_sort |
White, Jonathan Stuart |
title |
SANS investigations of the flux line lattice in unconventional superconductors |
title_short |
SANS investigations of the flux line lattice in unconventional superconductors |
title_full |
SANS investigations of the flux line lattice in unconventional superconductors |
title_fullStr |
SANS investigations of the flux line lattice in unconventional superconductors |
title_full_unstemmed |
SANS investigations of the flux line lattice in unconventional superconductors |
title_sort |
sans investigations of the flux line lattice in unconventional superconductors |
publisher |
University of Birmingham |
publishDate |
2009 |
url |
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.514083 |
work_keys_str_mv |
AT whitejonathanstuart sansinvestigationsofthefluxlinelatticeinunconventionalsuperconductors |
_version_ |
1719013813336932352 |