Observation of Phonon-Assisted Magnon Absorption in Spin-Orbit Coupling Induced Mott Insulator Sr${}_2$IrO${}_4$

Abstract

The infrared transmission measurement was performed for a two-dimensional spin-orbit coupling induced Mott insulator Sr${}_2$IrO${}_4$ with a layered-perovskite structure. A phonon-assisted magnon mode was observed at around 1870 cm${}^{-1}$ in the absorption spectrum below 180 K. The nearest-neighbor superexchange interaction $J$ was estimated to be 57 meV, which is about a half of the $J$ value of a copper oxide La${}_2$CuO${}_4$. Our results indicate the possibility that nontrivial properties such as superconductivity are realized at rather high temperature in iridium oxides.

References in corpus (3)

• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Novel Jeff = 1/2 Mott State Induced by Relativistic Spin-Orbit Coupling in Sr2IrO4
• Twisted Hubbard Model for Sr2IrO4: Magnetism and Possible High Temperature Superconductivity

Cited by in corpus (2)

• Direct observation of the Mott gap in strontium iridate with a scanning tunneling microscope
• Pseudospin heat conductivity in the $J_{\mathrm{eff}}=1/2$ antiferromagnet Sr${}_2$IrO${}_4$