Evidence for a Nodal-Line Superconducting State in LaFePO

Journal Article · Tue Feb 23 23:00:00 EST 2010 · Physical Review Letters

OSTI ID:972672

Fletcher, J D

In several iron-arsenide superconductors there is strong evidence for a fully gapped superconducting state consistent with either a conventional s-wave symmetry or an unusual s{sub {+-}} state where the gap changes sign between the electron and hole Fermi-surface sheets. Here we report measurements of the penetration depth {lambda}(T) in very clean samples of the related iron-phosphide superconductor, LaFePO, at temperatures down to {approx}100mK. We find that {lambda}(T) varies approximately linearly with T strongly suggesting the presence of gap nodes in this compound. Taken together with other data, this suggests the gap function is not universal for all pnictide superconductors.

• Research Organization: SLAC National Accelerator Laboratory (SLAC)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 972672
• Report Number(s): SLAC-REPRINT-2010-019
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 14 Vol. 102; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ELECTRONS
FERMI LEVEL
MATSCI
PENETRATION DEPTH
PNICTIDES
SUPERCONDUCTORS
SYMMETRY