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arXiv:1308.1209 · Journal of the Physical Society of Japan

Scaling Theory vs Exact Numerical Results for Spinless Resonant Level Model

Annamária Kiss, Junya Otsuki, Yoshio Kuramoto

Published Nov 20, 2013• 4 citations
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Abstract

The continuous-time quantum Monte Carlo method is applied to the interacting resonant level model (IRLM) using double expansion with respect to Coulomb interaction Ufc and hybridization V. Thermodynamics of the IRLM without spin is equivalent to the anisotropic Kondo model in the low-energy limit. Exact dynamics and thermodynamics of the IRLM are derived numerically for a wide range of Ufc with a given value of V. For negative Ufc, excellent agreement including a quantum critical point is found with a simple scaling formula that deals with V in the lowest-order, and Ufc up to infinite order. As Ufc becomes positive and large, lower order scaling results deviate from exact numerical results. Possible relevance of the results is discussed to certain Samarium compounds with unusual heavy-fermion behavior.

DOI
10.7566/jpsj.82.124713

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The continuous-time quantum Monte Carlo method is applied to the interacting resonant level model (IRLM) \nusing double expansion with respect to Coulomb interaction Ufc and hybridization V . Thermodynamics of the \nIRLM without spin is equivalent to the anisotropic Kondo model in the low-energy limit. Exact dynamics and \nthermodynamics of the IRLM are derived numerically for a wide range of Ufc with a given value of V . For \nnegative Ufc, excellent agreement including a quantum critical point is found with a simple scaling formula that \ndeals with V in the lowest-order, and Ufc up to infinite order. As Ufc becomes positive and large, lower order \nscaling results deviate from exact numerical results. Possible relevance of the results is discussed to certain \nSamarium compounds with unusual heavy-fermion behavior.
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