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arXiv · 1810.04092

Coherent and incoherent bands in La and Rh doped Sr3Ir2O7

V. Brouet·L. Serrier-Garcia·A. Louat·L. Fruchter·F. Bertran·P. Le Fevre·J. Rault·A Forget·D. Colson
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Abstract

In Sr2IrO4 and Sr3Ir2O7, correlations, magnetism and spin-orbit coupling compete on similar energy scales, creating a new context to study metal-insulator transitions (MIT). We use here Angle-Resolved photoemission to investigate the MIT as a function of hole and electron doping in Sr3Ir2O7, obtained respectively by Ir/Rh and Sr/La substitutions. We show that there is a clear reduction as a function of doping of the gap between a lower and upper band on both sides of the Fermi level, from 0.2eV to 0.05eV. Although these two bands have a counterpart in band structure calculations, they are characterized by a very different degree of coherence. The upper band exhibits clear quasiparticle peaks, while the lower band is very broad and loses weight as a function of doping. Moreover, their ARPES spectral weights obey different periodicities, reinforcing the idea of their different nature. We argue that a very similar situation occurs in Sr2IrO4 and conclude that the physics of the two families is essentially the same.

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V. Brouet, L. Serrier-Garcia, A. Louat, L. Fruchter, F. Bertran, P. Le Fevre, J. Rault, A Forget, D. Colson. 2018-10-09. Coherent and incoherent bands in La and Rh doped Sr3Ir2O7. https://doi.org/10.1103/physrevb.98.235101

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