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arXiv · 1802.00105

Can disorder act as a chemical pressure? An optical study of the Hubbard model

Himadri Barman·Mukul S. Laad·Syed R. Hassan
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Abstract

The optical properties have been studied using the dynamical mean-field theory (DMFT) on a disordered Hubbard model. Despite the fact that disorder turns a metal to an insulator in high dimensional correlated materials, we notice that it can enhance certain metallic behavior as if a chemical pressure is applied to the system resulting in an increase of the effective lattice bandwidth (BW). We study optical properties in such a scenario and compare results with experiments where the BW is changed through chemical doping and obtain remarkable similarities vindicating our claim. We also make a point that these similarities differ from some other forms of BW tuned optical effects.

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Himadri Barman, Mukul S. Laad, Syed R. Hassan. 2018-01-31. Can disorder act as a chemical pressure? An optical study of the Hubbard model. https://doi.org/10.1088/1361-648x/aabaa1

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