Synthesis, anisotropy, and superconducting properties of LiFeAs single crystal

Applied Physics Letters (Impact Factor: 3.79). 05/2010; 96(21):212508-212508-3. DOI: 10.1063/1.3435472
Source: arXiv

ABSTRACT A LiFeAs single crystal with Tconset ∼ 19.7 K was grown in a sealed tungsten crucible using the Bridgeman method. The electrical resistivity experiments revealed a ratio of room temperature to residual resistivity of approximately 46 and 18 for the in-plane and out-of plane directions, respectively. The estimated anisotropic resistivity, γρ = ρc/ρab, was approximately 3.3 at Tconset. The upper critical fields had large Hc2∥ab and Hc2∥c values of 83.4 T and 72.5 T, respectively, and an anisotropy ratio is γH = Hc2∥ab/Hc2∥c ∼ 1.15. The high upper critical field value and small anisotropy highlight the potential use of LiFeAs in a variety of applications. The calculated critical current density (Jc) from the M-H loop is approximately 103 A/cm2

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