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Mott-Hubbard transition in infinite dimensions

Ning-Hua Tong·Shun-Qing Shen·Fu-Cho Pu
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Abstract

We analyze the unanalytical structure of metal-insulator transition (MIT) in infinite dimensions. By introducing a simple transformation into the dynamical mean-field equation of Hubbard model, a multiple-valued structure in Green's function and other thermodynamical quantities with respect to the interaction strength $U$ are found at low temperatures. A unified description of stable, metastable and unstable phases is obtained in the regime $U_{c1}(T) 0$ evolves into second-order one at $U_{c2}(0)$ for $T=0 $. The phase diagram near MIT is presented.

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Ning-Hua Tong, Shun-Qing Shen, Fu-Cho Pu. 2001-09-01. Mott-Hubbard transition in infinite dimensions. https://doi.org/10.1103/physrevb.64.235109

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