Anisotropy in transport and magnetic properties of K0.64Fe1.44Se2

TL;DR

This study investigates the anisotropic transport and magnetic properties of K0.64Fe1.44Se2 single crystals, revealing significant resistivity anisotropy, weak magnetic susceptibility variation, and nearly isotropic critical currents, contributing to understanding iron-based superconductor behavior.

Contribution

It provides detailed measurements of anisotropic transport and magnetic properties of K0.64Fe1.44Se2, highlighting its weak anisotropy and comparing it with other iron-based superconductors.

Findings

Resistivity anisotropy up to tenfold between 1.8 K and 300 K.

Weak temperature dependence of magnetic susceptibility.

Nearly isotropic critical currents around 10-10^3 A/cm^2.

Abstract

We report a study of anisotropy in transport and magnetic properties of K0.64Fe1.44Se2.00 single crystals. The anisotropy in resistivity is up to one order of magnitude between 1.8 K and 300 K. Magnetic susceptibility exhibits weak temperature dependence in the normal state with decrease in temperature with no significant anomalies. The lower critical fields Hc1 of K0.64Fe1.44Se2.00 are only about 3 Oe and the anisotropy of Hc1,c/Hc1,ab is about 1. The critical currents for H||ab and H||c are about 10-10^3 A/cm2, smaller than in iron pnictides and in FeTe_{1-x}Se_{x} and nearly isotropic.