Large magnetoresistance and quantum oscillations observed in superconductingβ-IrSn₄

Diverse quantum phenomena have been observed in TSn₄transition metal (T) stannides, including superconductivity, nontrivial topology, and large magnetoresistance (MR) at low temperatures. Here, we report the experimental and theoretical investigation of tetragonalβ-IrSn₄(space groupI4₁/acd) with the lattice parametersa= 6.362(3) Å andc= 22.723(0) Å. The temperature dependence of the electrical resistivity indicates thatβ-IrSn₄is a good metal with Fermi-liquid behavior above the superconducting transition atT_c∼ 0.7 K. Magnetic susceptibility measurements indicate it is non-magnetic. However, positive transverse MR with linear field dependence is observed. AtT= 2 K andΜ₀H= 14 T, the MR reaches 700% without sign of saturation. Shubnikov-de Haas oscillations are observed from proximity detector oscillator measurements up to 60 T. We experimentally extract several frequencies, and through comparison to first-principles calculations, identify corresponding electronic bands. ForH//c, two strong oscillations,F₁≈ 109 andF₂≈ 302 T, allow us to determine effective masses 0.266m₀and 0.300m₀(m₀is the free-electron mass), respectively. The topology of these bands is discussed.