# Optical signature of a crossover from Mott- to Slater-type gap in ${\mathrm{Sr}}_{2}{\mathrm{Ir}}_{1\ensuremath{-}x}{\mathrm{Rh}}_{x}{\mathrm{O}}_{4}$

• Xu, Bîng University of Fribourg, Department of Physics and Fribourg Center for Nanomaterials, Fribourg, Switzerland
• Marsik, Premysl University of Fribourg, Department of Physics and Fribourg Center for Nanomaterials, Fribourg, Switzerland
• Sheveleva, Evgeniia University of Fribourg, Department of Physics and Fribourg Center for Nanomaterials, Fribourg, Switzerland
15.01.2020
Published in:
• Physical Review Letters. - 2020, vol. 124, no. 2, p. 027402
English With optical spectroscopy we provide evidence that the insulator-metal transition in Sr2Ir1−xRhxO4 occurs close to a crossover from the Mott- to the Slater-type. The Mott gap at x=0 persists to high temperature and evolves without an anomaly across the Néel temperature, TN. Upon Rh doping, it collapses rather rapidly and vanishes around x=0.055. Notably, just as the Mott gap vanishes yet another gap appears that is of the Slater-type and develops right below TN. This Slater gap is only partial and is accompanied by a reduced scattering rate of the remaining free carriers, similar as in the parent compounds of the iron arsenide superconductors.
Faculty
Faculté des sciences et de médecine
Department
Département de Physique
Language
• English
Classification
Physics