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arXiv · 2309.10030

An Exactly Solvable Model of Randomly Pinned Charge Density Waves in Two Dimensions

Matthew C. O'Brien·Eduardo Fradkin
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Abstract

The nature of the interplay between fluctuations and quenched random disorder is a long-standing open problem, particularly in systems with a continuous order parameter. This lack of a full theoretical treatment has been underscored by recent advances in experiments on charge density wave materials. To address this problem, we formulate an exactly solvable model of a two-dimensional randomly pinned incommensurate charge density wave, and use the large-$N$ technique to map out the phase diagram and order parameter correlations. Our approach captures the physics of the Berezinskii-Kosterlitz-Thouless phase transition in the clean limit at large $N$. We pay particular attention to the roles of thermal fluctuations and quenched random field disorder in destroying long-range order, finding a novel crossover between weakly- and strongly-disordered regimes.

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Matthew C. O'Brien, Eduardo Fradkin. 2023-09-18. An Exactly Solvable Model of Randomly Pinned Charge Density Waves in Two Dimensions. https://doi.org/10.1088/1742-5468%2Fad17b3

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