TY - JOUR
T1 - Anisotropic fluctuations and quasiparticle excitations in FeSe 0.5 Te0.5
AU - Serafin, A.
AU - Coldea, A. I.
AU - Ganin, A. Y.
AU - Rosseinsky, M. J.
AU - Prassides, K.
AU - Vignolles, D.
AU - Carrington, A.
PY - 2010/9/20
Y1 - 2010/9/20
N2 - We present data for the temperature dependence of the magnetic penetration depth λ (T), heat capacity C (T), resistivity ρ (T), and magnetic torque τ for highly homogeneous single-crystal samples of Fe1.0 Se0.44 (4) Te0.56 (4). λ (T) was measured down to 200 mK in zero field. We find λ (T) follows a power law Δλ∼ Tn with n=2.2±0.1. This is similar to some 122 iron arsenides and likely results from a sign-changing pairing state combined with strong scattering. Magnetic fields of up to B=55 or 14 T were used for the τ (B) and C (T) /ρ (T) measurements, respectively. The specific heat, resistivity, and torque measurements were used to map out the (H,T) phase diagram in this material. All three measurements were conducted on exactly the same single-crystal sample so that the different information revealed by these probes is clearly distinguished. Heat-capacity data strongly resemble those found for the high- Tc cuprates, where strong fluctuation effects wipe out the phase transition at Hc2. Unusually, here we find the fluctuation effects appear to be strongly anisotropic.
AB - We present data for the temperature dependence of the magnetic penetration depth λ (T), heat capacity C (T), resistivity ρ (T), and magnetic torque τ for highly homogeneous single-crystal samples of Fe1.0 Se0.44 (4) Te0.56 (4). λ (T) was measured down to 200 mK in zero field. We find λ (T) follows a power law Δλ∼ Tn with n=2.2±0.1. This is similar to some 122 iron arsenides and likely results from a sign-changing pairing state combined with strong scattering. Magnetic fields of up to B=55 or 14 T were used for the τ (B) and C (T) /ρ (T) measurements, respectively. The specific heat, resistivity, and torque measurements were used to map out the (H,T) phase diagram in this material. All three measurements were conducted on exactly the same single-crystal sample so that the different information revealed by these probes is clearly distinguished. Heat-capacity data strongly resemble those found for the high- Tc cuprates, where strong fluctuation effects wipe out the phase transition at Hc2. Unusually, here we find the fluctuation effects appear to be strongly anisotropic.
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U2 - 10.1103/PhysRevB.82.104514
DO - 10.1103/PhysRevB.82.104514
M3 - Article
AN - SCOPUS:77957558311
VL - 82
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
SN - 0163-1829
IS - 10
M1 - 104514
ER -