In-plane and interlayer magnetoresistance in FeSe

Abstract

We report measurements of the in-plane and interlayer magnetoresistances of FeSe. The in-plane magnetoresistance $\hat{I}”\ddot{I}{}_{ab}/\ddot{I}{}_{ab}(0)$ for $B\parallel c$ is positive below $T_s$ and increases with decreasing temperature, exceeding 2.5 at $T$ = 10 K and $B$ = 14 T. The field-direction dependence indicates that the in-plane magnetoresistance is basically determined by the $c$-axis component of the magnetic field. The interlayer magnetoresistance $\hat{I}”\ddot{I}{}_c/\ddot{I}{}_c(0)$ is negative below $T_s$ but turns positive below $\sim$18 K, which is probably due to the contamination by the large in-plane magnetoresistance. The field-direction dependence of the interlayer magnetoresistance can approximately be described by a standard formula for quasi-two-dimensional electron systems except near $B\parallel ab$. The experimental magnetoresistance near $B\parallel ab$ is larger than the formula, which can be attributed to the so-called interlayer coherence peak. The large width of the peak indicates the correspondingly large interlayer transfer energy.

15 pages, 7 figures