Magnetism and electrical transport in Y-doped layered iridate Sr$_2$IrO$_4$

Abstract: Here, we report an investigation of structural, magnetic and electronic properties in Y-doped layered iridate (Sr$_{1-x}$Y$_x$)$_2$IrO$_4$ ($x$ $\leq$ 0.1). The parent Sr$_2$IrO$_4$ is a well-studied spin-orbit coupling (SOC) induced insulator with an antiferromagnetic ground state. The Y-doping here equivalently acts for electron doping without altering the vital parameters such as, SOC and electron correlation. Experimental results show a minute change in structural parameters and an equivalent charge conversion from Ir$^{4+}$ to Ir$^{3+}$. Unlike similarly other electron-doped system, the low temperature magnetic and electronic state in present series is minimally influenced. The charge conduction mechanism follows 2-dimensional hopping model in whole series. Magnetoresistance (MR) data show an interesting sign change with both temperature and magnetic field. The positive MR both at low temperature follows weak antilocalization behavior where the sign change in MR is believed to be caused by an interplay between SOC and magnetic moment.