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arXiv:2505.08925 · Physical review. B./Physical review. B

Collective excitations and stability of a non-Fermi liquid state near a quantum critical point of a metal

Yasha Gindikin, Dmitrii L. Maslov, Andrey V. Chubukov

Published Jul 18, 2025• 0 citations
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Abstract

At the edge of a phase transition in certain quantum materials, electrons can enter an exotic ``strange metal'' state, where they cease behaving like well-defined quasiparticles. The authors investigate here whether this state, in an isotropic system, is internally stable against perturbations with different angular momenta. By developing a theoretical framework to trace collective electron oscillations through the crossover from a Fermi liquid to a non-Fermi liquid regime, the authors demonstrate that the system remains stable under perturbations with all angular momenta --- including the odd-momentum modes whose stability was previously questioned.

DOI
10.1103/cbkc-gj3b

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