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Temperature dependent band structure of the Kondo insulator

C. Groeber·R. Eder
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Abstract

We present a Qantum Monte Carlo (QMC) study of the temperature dependent dynamics of the Kondo insulator. Working at the so-called symmetrical point allows to perform minus-sign free QMC simulations and thus reach temperatures of less than 1% of the conduction electron bandwidth. Study of the temperature dependence of the single particle Green's function and dynamical spin correlation function shows a surprisingly intricate low temperature band structure and gives evidence for two characteristic temperatures, which we identify with the Kondo and coherence temperature, respectively. In particular, the data show a temperature induced metal-insulator transition at the coherence temperature.

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C. Groeber, R. Eder. 1998-01-08. Temperature dependent band structure of the Kondo insulator. https://doi.org/10.1103/physrevb.57.r12659

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