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arXiv · 1503.04630

Universality Class of the Mott Transition

M. Abdel-Jawad·R. Kato·I. Watanabe·N. Tajima·Y. Ishii
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Abstract

Pressure dependence of the conductivity and thermoelectric power is measured through the Mott transition in the layer organic conductor EtMe3P[Pd(dmit)2]2. The critical behavior of the thermoelectric effect provides a clear and objective determination of the Mott-Hubbard transition during the isothermal pressure sweep. Above the critical end point, the metal-insulator crossing, determined by the thermoelectric effect minimum value, is not found to coincide with the maximum of the derivative of the conductivity as a function of pressure. We show that the critical exponents of the Mott-Hubbard transition fall within the Ising universality class regardless of the dimensionality of the system.

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M. Abdel-Jawad, R. Kato, I. Watanabe, N. Tajima, Y. Ishii. 2015-03-16. Universality Class of the Mott Transition. https://doi.org/10.1103/physrevlett.114.106401

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