Strongly correlated systems in which spin, lattice, orbital, and charge are closely related have attracted great interest for their fascinating physical properties includ- ing multiferroicity, magnetism, superconductivity, etc. Such a novel properties have been found in transition metal oxides (TMOs). Spin-orbit coupling (SOC) is an im- portant factor in determining the electronic and magnetic environment of strongly correlated TMOs. All crystals show a SOC behavior, even though its effects are different. SOC arises when the electrons feel a relativistic field from the nucleus; the degree of the SOC becomes larger when the atomic weight increases. Many un- usual phenomena observed in Sr2IrO4 in this study could be attributed to the total angular momentum induced by strong SOC and Hubbard repulsion. We have in- vestigated the physical properties of Sr2IrO4 in various electronic, magnetic, and magnetoelectronic environments. These environments were obtained by changing parameters such as the field strength and orientation, and the temperature. Further- more, we have investigated the parameters to modify the strength of the SOC by chemical doping and creation of oxygen vacancies.
Thesis Advisor: Prof. Younjung Jo