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arXiv · 2409.02236

Umklapp-driven first-order transition into a charge-density wave phase

A. V. Rozhkov
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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.

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A. V. Rozhkov. 2024-09-03. Umklapp-driven first-order transition into a charge-density wave phase. https://doi.org/10.1103/physrevb.111.205434

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