Spectroscopic evidence for electron-boson coupling in electron-doped Sr${}_2$IrO${}_4$

Abstract

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 of 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.

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Cited by in corpus (5)

• Superconductivity in high-$T_c$ and related strongly correlated systems from variational perspective: Beyond mean field theory
• Strain-engineering of the charge and spin-orbital interactions in Sr2IrO4
• Constrained-Path Auxiliary-Field Quantum Monte Carlo for Coupled Electrons and Phonons
• A Hubbard exciton fluid in a photo-doped antiferromagnetic Mott insulator
• Anomalous Nodal Gap in a Doped Spin-1/2 Antiferromagnetic Mott Insulator