Abstract
Lowerature specific heat is measured on the overdoped Ba(Fe 1-xCox)2As2 (x = 0:13) single crystal under magnetic fields along three different directions. A clear anisotropy is observed on the field dependent electronic specific heat coefficient γ(H). The value of γ(H) is obviously larger with magnetic field along [001] (c-axis) than that within the ab-plane of the crystal lattice, which cannot be attributed to the effect by anisotropy of the upper critical field. Meanwhile, the data show a rather small difference when the direction of the field is rotated from [100] to [110] direction within the ab-plane. Our results suggest that a considerable part of the line nodes is not excited to contribute to the quasiparticle density of states by the field when the field is within the ab-plane. The constraints on the topology of the gap nodes are discussed based on our observations.
Original language | English |
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Article number | 054714 |
Journal | journal of the physical society of japan |
Volume | 82 |
Issue number | 5 |
DOIs | |
Publication status | Published - 2013 May |
Keywords
- Ba(fe Co)as
- Fe-based superconductors
- Gap structure
- Line nodes
- Specific heat
ASJC Scopus subject areas
- Physics and Astronomy(all)