The University of Southampton
University of Southampton Institutional Repository

Letter. Unconventional superconductivity in Ba0.6K0.4Fe2As2 from inelastic neutron scattering

Letter. Unconventional superconductivity in Ba0.6K0.4Fe2As2 from inelastic neutron scattering
Letter. Unconventional superconductivity in Ba0.6K0.4Fe2As2 from inelastic neutron scattering
A new family of superconductors containing layers of iron arsenide has attracted considerable interest because of their high transition temperatures (Tc), some of which are >50 K, and because of similarities with the high-Tc copper oxide superconductors. In both the iron arsenides and the copper oxides, superconductivity arises when an antiferromagnetically ordered phase has been suppressed by chemical doping. A universal feature of the copper oxide superconductors is the existence of a resonant magnetic excitation, localized in both energy and wavevector, within the superconducting phase. This resonance, which has also been observed in several heavy-fermion superconductors, is predicted to occur when the sign of the superconducting energy gap takes opposite values on different parts of the Fermi surface, an unusual gap symmetry which implies that the electron pairing interaction is repulsive at short range. Angle-resolved photoelectron spectroscopy shows no evidence of gap anisotropy in the iron arsenides, but such measurements are insensitive to the phase of the gap on separate parts of the Fermi surface. Here we report inelastic neutron scattering observations of a magnetic resonance below Tc in Ba0.6K0.4Fe2As2, a phase-sensitive measurement demonstrating that the superconducting energy gap has unconventional symmetry in the iron arsenide superconductors.
0028-0836
930-932
Christianson, A.D.
f72ae15b-1a06-426c-bfdb-5f19fee9837b
Goremychkin, E.A.
37f2b8ac-14dc-4957-9864-b490d9853451
Osborn, R.
12b613a4-baca-43c0-835f-9dc31a5e6a90
Rosenkranz, S.
44bc2d47-acdb-40bf-9d45-ca962617f0a1
Lumsden, M.D.
abb3e092-91ec-4a42-b854-4aff355cc906
Malliakas, C.D.
d606ddfa-5a65-4c2f-9fea-78e39e49bdc8
Todorov, I.S.
0dc1682a-8744-4c28-bc45-0004004459d2
Claus, H.
82561206-8e0d-4164-9a61-5ffe699a7f95
Chung, D.Y.
76308cb8-e635-44c8-a909-0047d169e998
Kanatzidis, M.G.
92475e9a-c256-4fe7-b02d-7b36895fc9a3
Bewley, R.I.
737eb157-f5d9-4cc0-bea2-d53c194a998e
Guidi, T.
6b233769-0059-4a2a-addf-f832ec2184eb
Christianson, A.D.
f72ae15b-1a06-426c-bfdb-5f19fee9837b
Goremychkin, E.A.
37f2b8ac-14dc-4957-9864-b490d9853451
Osborn, R.
12b613a4-baca-43c0-835f-9dc31a5e6a90
Rosenkranz, S.
44bc2d47-acdb-40bf-9d45-ca962617f0a1
Lumsden, M.D.
abb3e092-91ec-4a42-b854-4aff355cc906
Malliakas, C.D.
d606ddfa-5a65-4c2f-9fea-78e39e49bdc8
Todorov, I.S.
0dc1682a-8744-4c28-bc45-0004004459d2
Claus, H.
82561206-8e0d-4164-9a61-5ffe699a7f95
Chung, D.Y.
76308cb8-e635-44c8-a909-0047d169e998
Kanatzidis, M.G.
92475e9a-c256-4fe7-b02d-7b36895fc9a3
Bewley, R.I.
737eb157-f5d9-4cc0-bea2-d53c194a998e
Guidi, T.
6b233769-0059-4a2a-addf-f832ec2184eb

Christianson, A.D., Goremychkin, E.A., Osborn, R., Rosenkranz, S., Lumsden, M.D., Malliakas, C.D., Todorov, I.S., Claus, H., Chung, D.Y., Kanatzidis, M.G., Bewley, R.I. and Guidi, T. (2008) Letter. Unconventional superconductivity in Ba0.6K0.4Fe2As2 from inelastic neutron scattering. Nature, 456 (7224), 930-932. (doi:10.1038/nature07625).

Record type: Article

Abstract

A new family of superconductors containing layers of iron arsenide has attracted considerable interest because of their high transition temperatures (Tc), some of which are >50 K, and because of similarities with the high-Tc copper oxide superconductors. In both the iron arsenides and the copper oxides, superconductivity arises when an antiferromagnetically ordered phase has been suppressed by chemical doping. A universal feature of the copper oxide superconductors is the existence of a resonant magnetic excitation, localized in both energy and wavevector, within the superconducting phase. This resonance, which has also been observed in several heavy-fermion superconductors, is predicted to occur when the sign of the superconducting energy gap takes opposite values on different parts of the Fermi surface, an unusual gap symmetry which implies that the electron pairing interaction is repulsive at short range. Angle-resolved photoelectron spectroscopy shows no evidence of gap anisotropy in the iron arsenides, but such measurements are insensitive to the phase of the gap on separate parts of the Fermi surface. Here we report inelastic neutron scattering observations of a magnetic resonance below Tc in Ba0.6K0.4Fe2As2, a phase-sensitive measurement demonstrating that the superconducting energy gap has unconventional symmetry in the iron arsenide superconductors.

Full text not available from this repository.

More information

Published date: December 2008
Organisations: Quantum, Light & Matter Group

Identifiers

Local EPrints ID: 154941
URI: https://eprints.soton.ac.uk/id/eprint/154941
ISSN: 0028-0836
PURE UUID: a35aa7a0-66cf-4773-b019-0d133ca4ffc1

Catalogue record

Date deposited: 26 May 2010 13:46
Last modified: 16 Jul 2019 23:58

Export record

Altmetrics

Contributors

Author: A.D. Christianson
Author: E.A. Goremychkin
Author: R. Osborn
Author: S. Rosenkranz
Author: M.D. Lumsden
Author: C.D. Malliakas
Author: I.S. Todorov
Author: H. Claus
Author: D.Y. Chung
Author: M.G. Kanatzidis
Author: R.I. Bewley
Author: T. Guidi

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of https://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×