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Finite-temperature Mott transitions in multi-orbital Hubbard model

Kensuke Inaba·Akihisa Koga·Sei-ichiro Suga·Norio Kawakami
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Abstract

We investigate the Mott transitions in the multi-orbital Hubbard model at half-filling by means of the self-energy functional approach. The phase diagrams are obtained at finite temperatures for the Hubbard model with up to four-fold degenerate bands. We discuss how the first-order Mott transition points $U_{c1}$ and $U_{c2}$ as well as the critical temperature $T_c$ depend on the orbital degeneracy. It is elucidated that enhanced orbital fluctuations play a key role to control the Mott transitions in the multi-orbital Hubbard model.

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Kensuke Inaba, Akihisa Koga, Sei-ichiro Suga, Norio Kawakami. 2005-06-06. Finite-temperature Mott transitions in multi-orbital Hubbard model. https://doi.org/10.1103/physrevb.72.085112

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