Spectroscopic Evidence for Electron-Boson Coupling in Electron-Doped Sr2IrO4

Yong Hu, Xiang Chen, S.-T. Peng, C. Lane, M. Matzelle, Z.-L. Sun, M. Hashimoto, D.-H. Lu, E. F. Schwier, M. Arita, T. Wu, R. S. Markiewicz (+6 others)
2019 Physical Review Letters  
The pseudogap, d-wave superconductivity and electron-boson coupling are three intertwined key ingredients in the phase diagram of the cuprates. Sr_{2}IrO_{4} is a 5d-electron counterpart of the cuprates in which both the pseudogap and a d-wave instability have been observed. Here, we report spectroscopic evidence for the presence of the third key player in electron-doped Sr_{2}IrO_{4}: electron-boson coupling. A kink in nodal dispersion is observed with an energy scale of ∼50 meV. The strength
more » ... f the kink changes with doping, but the energy scale remains the same. These results provide the first noncuprate platform for exploring the relationship between the pseudogap, d-wave instability, and electron-boson coupling in doped Mott insulators.
doi:10.1103/physrevlett.123.216402 pmid:31809181 fatcat:vdokanawaba3vg7j2fsrgdqrxm