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arXiv · 0901.2706

Surface dead layer for quasiparticles near a Mott transition

Giovanni Borghi·Michele Fabrizio·Erio Tosatti
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Abstract

Electron quasiparticles are progressively weakened by correlations upon approaching a continuos Mott metal insulator transition in a bulk solid. We show that corresponding to the bulk weakening, a dead layer forms below the surface of the solid, where quasiparticles are exponentially suppressed. The surface dead layer depth is a bulk property, and diverges when the Mott transition is approached. We describe this phenomenon in a Hubbard model within a self-consistent Gutzwiller approximation. Photoemission data of Rodolakis et al. in V2O3 appear to be in accord with this physical picture.

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Giovanni Borghi, Michele Fabrizio, Erio Tosatti. 2009-01-18. Surface dead layer for quasiparticles near a Mott transition. https://doi.org/10.1103/physrevlett.102.066806

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