arXiv:2308.03590 · Physical review. B./Physical review. B

Systematic compactification of the two-channel Kondo model. II. Comparative study of scaling and universality

Aleksandar Ljepoja, Nayana Shah, C. J. Bolech

Published Jul 8, 2024• 3 citations

Abstract

Following up on the systematic compactification of the two-channel Kondo model [and its multichannel extensions; see Ljepoja et al., Phys. Rev. B 110, 045108 (2024)] and the demonstration of its validity over the past proposal of compactification, we resort to a study of scaling using Anderson's simple poor man's procedure to carry out a comparative study of these two and the original model. By doing so we unveil a universal agreement among the three models in how they flow upon scaling, and suggest the general limits of such a concordance. In this way we further elucidate the conditions under which the standard simplifications implicit in many bosonization-based mappings (particularly of quantum impurity models) can be used reliably, and when the consistent bosonization-debosonization approach is needed.

DOI: 10.1103/physrevb.110.045109

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