Effects of phosphorus doping on the physical properties of axion insulator candidate EuIn₂As₂

We report an investigation on the single crystal growth, magnetic and transport properties of EuIn₂(As_1-xP_x)₂ (0≤x≤ 1). The physical properties of axion insulator candidate EuIn₂As₂ can be effectively tuned by P-doping. With increasing x, the c-axis lattice parameter decreases linearly, the magnetic transition temperature gradually increases and ferromagnetic interactions are enhanced. This is similar to the previously reported high pressure effect on EuIn₂As₂. For x=0.40, a spin glass state at T_g=10 K emerges together with the observations of a butter-fly shaped magnetic hysteresis and slow magnetic behavior. Besides, magnetic transition has great influence on the charge carriers in this system and negative colossal magnetoresistance is observed for all P-doped samples. Our findings suggest that EuIn₂(As_1-xP_x)₂ is a promising material playground for exploring novel topological states.