- Letter
Kohn's theorem applied to quantum oscillations in cuprates
Phys. Rev. B 111, L041107 – Published 13 January, 2025
DOI: https://doi.org/10.1103/PhysRevB.111.L041107
Abstract
In this Letter I apply Kohn's theorem to quantum oscillations in cuprates. I show that when combined with Gell-Mann and Low theorem, there is rigorous justification of quantum oscillations as in a Fermi liquid for cuprates. For simplicity, understanding the lack of interaction effects in quantum oscillations can be addressed in the language of a fully translationally invariant system. The Gell-Mann and Low theorem is not perturbative, and applies more generally as long as the adiabatic evolution from an isolated nondegenerate state is the case. Oscillation frequencies are identical to the noninteracting problem. It is the cyclotron gap that justifies Fermi-liquid-based theory of quantum oscillations. This is not to imply that other properties of the cuprates that do not have a gap in the spectrum could not exhibit non-Fermi-liquid behavior, for example, angle-resolved photoemission spectroscopy.
