Effect of valence fluctuations on the ground state properties of SmB6

Abstract

We argue that because of valence-fluctuation caused dynamical changes (fluctuations) of impurity energies in the impurity band of SmB6, energies of electrons occupying impurity sites can be due to the uncertainty principle only estimated with corresponding uncertainty, so they can be represented by energy intervals of non-zero width. As a conse- quence, both occupied as well as unoccupied states can be found in the impurity band above as well as below Fermi level even in the ground state. Therefore the subsystem of localized charge carriers in the ground state of SmB6 cannot be described by an energy distribution function expected for T = 0 K. This fundamental conclusion adds another reason for absence of resistivity divergence in SmB6 at lowest temperatures, and sheds new light on interpretation of experimental data obtained for SmB6 and similar systems at lowest temperatures.

References in corpus (6)

• Surface electronic structure of the topological Kondo insulator candidate correlated electron system SmB6
• Correlated Topological Insulators with Mixed Valence
• Tuning bulk and surface conduction in topological Kondo insulator SmB6
• Emergence of a coherent in-gap state in SmB6 Kondo insulator revealed by scanning tunneling spectroscopy
• One-dimensional edge state transport in a topological Kondo insulator
• Breakdown of the Kondo insulating state in SmB6 by introducing Sm vacancies