Absolute value and temperature dependence of the magnetic penetration depth in Ba(Co 0.074Fe 0.926) 2As 2
2012 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 85, no 6, 060506- p.Article in journal (Refereed) Published
The absolute value and temperature dependence of the in-plane magnetic penetration depth lambda have been measured on a single crystal of Ba(Co0.074Fe0.926)(2)As-2 using low-energy muon-spin rotation and microwave cavity perturbation. The magnetic field profiles in the Meissner state are consistent with a local London model beyond a depth of 15 nm. We determine the gap symmetry through measurements of the temperature dependence of the superfluid density which follows a two-gap s-wave model over the entire temperature range below T-c. While the intermediate to high temperature data is well fit by an energy gap model in the BCS-like (weak-coupling) limit, a second smaller gap becomes apparent at low temperatures.
Place, publisher, year, edition, pages
2012. Vol. 85, no 6, 060506- p.
Mu-Sr; Superconductor; Yba2cu3o6.95; Surface; Psi
IdentifiersURN: urn:nbn:se:kth:diva-99606DOI: 10.1103/PhysRevB.85.060506ISI: 000300830500001ScopusID: 2-s2.0-84863260853OAI: oai:DiVA.org:kth-99606DiVA: diva2:542434
QC 201506262012-08-012012-08-012015-06-26Bibliographically approved