Anisotropic $H_{c2}$ determined up to 92 T and the signature of multi-band superconductivity in Ca$_{10}$(Pt$_{4}$As$_{8}$)((Fe$_{1-x}$Pt$_{x}$)$_{2}$As$_{2}$)$_{5}$ superconductor

Eundeok Mun; Ni Ni; Jared M. Allred; Robert J. Cava; Oscar Ayala; Ross D. McDonald; Neil Harrison; Vivien S. Zapf

doi:10.1103/PhysRevB.85.100502

paper

Anisotropic $H_{c 2}$ determined up to 92 T and the signature of multi-band superconductivity in Ca $_{10}$ (Pt $_{4}$ As $_{8}$ )((Fe $_{1 - x}$ Pt $_{x}$ ) $_{2}$ As $_{2}$ ) $_{5}$ superconductor

arXiv:1202.5011 · doi:10.1103/PhysRevB.85.100502

Abstract

The upper critical fields, $H_{c 2}$ ( $T$ ), of single crystals of the superconductor Ca $_{10}$ (Pt $_{4 - δ}$ As $_{8}$ )((Fe $_{0.97}$ Pt $_{0.03}$ ) $_{2}$ As $_{2}$ ) $_{5}$ ( $δ$ $\approx$ 0.246) are determined over a wide range of temperatures down to $T$ = 1.42 K and magnetic fields of up to $μ_{0} H$ $≃$ 92 T. The measurements of anisotropic $H_{c 2}$ ( $T$ ) curves are performed in pulsed magnetic fields using radio-frequency contactless penetration depth measurements for magnetic field applied both parallel and perpendicular to the \textbf{ab}-plane. Whereas a clear upward curvature in $H_{c 2}^{∥ c}$ ( $T$ ) along \textbf{H} $∥$ \textbf{c} is observed with decreasing temperature, the $H_{c 2}^{∥ ab}$ ( $T$ ) along \textbf{H} $∥$ \textbf{ab} shows a flattening at low temperatures. The rapid increase of the $H_{c 2}^{∥ c}$ ( $T$ ) at low temperatures suggests that the superconductivity can be described by two dominating bands. The anisotropy parameter, $γ_{H}$ $\equiv$ $H_{c 2}^{∥ ab} / H_{c 2}^{∥ c}$ , is $\sim$ 7 close to $T_{c}$ and decreases considerably to $\sim$ 1 with decreasing temperature, showing rather weak anisotropy at low temperatures.

4pages, 3figures, accepted PRB Rapid Communication

Anisotropic $H_{c 2}$ determined up to 92 T and the signature of multi-band superconductivity in Ca $_{10}$ (Pt $_{4}$ As $_{8}$ )((Fe $_{1 - x}$ Pt $_{x}$ ) $_{2}$ As $_{2}$ ) $_{5}$ superconductor

Abstract

References in corpus (13)

Cited by in corpus (16)

Anisotropic Hc2​ determined up to 92 T and the signature of multi-band superconductivity in Ca10​(Pt4​As8​)((Fe1−x​Ptx​)2​As2​)5​ superconductor

Abstract

References in corpus (13)

Cited by in corpus (16)

Anisotropic $H_{c 2}$ determined up to 92 T and the signature of multi-band superconductivity in Ca $_{10}$ (Pt $_{4}$ As $_{8}$ )((Fe $_{1 - x}$ Pt $_{x}$ ) $_{2}$ As $_{2}$ ) $_{5}$ superconductor