Tuning of Spin-Orbit Coupling and Electronic Correlation in Pyrochlore Iridate
by Dr. Harish Kumar (Research Scholar, Jawaharlal Nehru University, New Delhi)
Thursday, October 10, 2019 from to (Asia/Kolkata)
The 5d based pyrochlore iridates (A2Ir2O7) have recently attracted a lot of attention due to its inherent magnetic frustration and the presence of iridium . In general, iridium exhibits large spin-orbit coupling (SOC) effect due to the heavy nature of iridium. On the other hand, the electronic correlation (U) effect reduces substantially due to the extended character of 5d orbitals. In these materials, SOC, U and crystal field effect (CFE) show a comparable strength. Therefore, a variety of quantum phases has been proposed due to an exotic interplay between SOC and U [1, 2]. In this talk, we will discuss the structural, electronic and magnetic properties of pyrochlore iridate Y2Ir2O7 which is an ideal system to the study combined physics of magnetic frustration, SOC and U on electronic and magnetic properties because Y3+ is nonmagnetic. We will discuss its evolution with magnetic Ru and nonmagnetic Ti doping at Ir-site (Y2(Ir1-xMx)2O7, M = Ru and Ti) while magnetic Pr at Y-site ((Y1-xPrx)2Ir2O7) which are aimed to tune the vital interactions (SOC, U and possible f-d exchange interaction) [4, 5, 6]. References: 1. D. Pesin et al Nat. Phys. 6, 376 (2010). 2. W. Witczak-Krempa, et al Annual Rev. Condens. Matter Phys. 5, 57 (2014). 3. H. Kumar et al. J. Magn. Magn. Mater 409, 20(2016), 4. H. Kumar et al. Phys. Rev. B 95, 054415 (2017), 5. H. Kumar et al. J. Phys. Chem. C 123, 13036 (2019). 6. H. Kumar et al. J. Magn. Magn. Mater. 478, 148 (2019).