Temperature dependence of Raman scattering spectra of SrIrO₃ thin films

The electronic states of a three-dimensional perovskite compound SrIrO₃ are characterized by spin-orbit interactions. In this compound, the half-filled j_eff = 1/2 band shows semimetallic properties. We have measured the Raman scattering spectra of SrIrO₃ thin films fabricated on DyScO₃ substrates [1]. In the Raman scattering spectra, a broad spectral component is observed at about 0.1 eV in addition to many phonon peaks. The energy of this broad structure is slightly lower than that of the electronic excitation within the j_eff = 1/2 band [2]. We have studied this structure in detail. The temperature dependence of the structure is different from that of the phonon peaks. In this presentation, we discuss the origin of the spectral structure not only from the viewpoint of the phonon modes but also from the viewpoint of the electronic excitation.

[1] S. Hori et al., Appl. Phys. Lett. 121, 022402 (2022).

[2] J. Fujioka et al., Phys. Rev. B 95, 121102(R) (2017).