In-plane and interlayer magnetoresistance in FeSe

We report measurements of the in-plane and interlayer magnetoresistance on FeSe. The in-plane magnetoresistance Δρab/ρab(0) for B ∥ c is positive below Tₛ and grows 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 Δρc/ρc(0) is negative below Tₛ but turns positive below ~18 K, which is probably due to the contamination of 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 ∥ ab. The experimental magnetoresistance near B ∥ 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.