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The types of Mott insulator

Dung-Hai Lee·Steven A. Kivelson
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Abstract

There are two classes of Mott insulators in nature, distinguished by their responses to weak doping. With increasing chemical potential, Type I Mott insulators undergo a first order phase transition from the undoped to the doped phase. In the presence of long-range Coulomb interactions, this leads to an inhomogeneous state exhibiting ``micro-phase separation.'' In contrast, in Type II Mott insulators charges go in continuously above a critical chemical potential. We show that if the insulating state has a broken symmetry, this increases the likelihood that it will be Type I. There exists a close analogy between these two types of Mott insulators and the familiar Type I and Type II superconductors.

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Dung-Hai Lee, Steven A. Kivelson. 2002-08-27. The types of Mott insulator. https://doi.org/10.1103/physrevb.67.024506

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