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arXiv · 0808.0913

Electronic Griffiths phase of the d=2 Mott transition

E. C. Andrade·E. Miranda·V. Dobrosavljevic
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Abstract

We investigate the effects of disorder within the T=0 Brinkman-Rice (BR) scenario for the Mott metal-insulator transition (MIT) in two dimensions (2d). For sufficiently weak disorder the transition retains the Mott character, as signaled by the vanishing of the local quasiparticles (QP) weights Z_{i} and strong disorder screening at criticality. In contrast to the behavior in high dimensions, here the local spatial fluctuations of QP parameters are strongly enhanced in the critical regime, with a distribution function P(Z) ~ Z^{α-1} and αtends to zero at the transition. This behavior indicates a robust emergence of an electronic Griffiths phase preceding the MIT, in a fashion surprisingly reminiscent of the "Infinite Randomness Fixed Point" scenario for disordered quantum magnets.

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E. C. Andrade, E. Miranda, V. Dobrosavljevic. 2009-05-05. Electronic Griffiths phase of the d=2 Mott transition. https://doi.org/10.1103/physrevlett.102.206403

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