Emergence of 1/3 magnetization plateau and successive magnetic transitions in Zintl phase Eu3InAs3

Single crystals of Eu3InAs3 have been successfully synthesized by indium flux reactions. Eu3InAs3 crystallizes in the Ca3AlAs3-type structure with an orthorhombic space-group Pnma. Theoretical calculations indicate that Eu3InAs3 is a semiconductor with a direct band gap of 0.3 eV. Eu3InAs3 has large negative Seebeck coefficients in the range of 300-450 mu V/K at room temperature. Eu3InAs3 displays two antiferromagnetic transitions (TN1 = 13 and TN2 = 10 K) for both H II b and H perpendicular to b which can be suppressed by magnetic fields. At 2 K, field-induced ferromagnetic states are reached for both H II b and H perpendicular to b. Particularly, the H II b magnetization curves show a plateau at 1/3 of the saturated magnetization and an anomaly at 2/3 of the saturated magnetization. Eu3InAs3 is a Zintl phase material showing a 1/3 magnetization plateau here.