Umklapp-driven first-order transition into a charge-density wave phase
Abstract
Using phenomenological Landau free energy, we systematically analyze influence of so-called umklapp contributions on the phase diagram of a solid hosting a commensurate charge-density wave phase. The umklapp terms may change the transition into the ordered state from continuous (second-order) to discontinuous (first-order). Additional elements, such as critical and tricritical points, emerge on the phase diagram under suitable conditions. The proposed mechanism is generalized for the case of nearly-commensurate charge-density wave, as well as spin-density wave orders. Several charge-density-wave-hosting alloys are used as experimentally available examples illustrating the formalism.
Keywords
Cite
@article{arxiv.2409.02236,
title = {Umklapp-driven first-order transition into a charge-density wave phase},
author = {A. V. Rozhkov},
journal= {arXiv preprint arXiv:2409.02236},
year = {2025}
}
Comments
13 pages, 6 figures; the text is extended; two appendices, a figure, and several references are added; this version is virtually identical to the published paper