Dynamic phases and reentrant Hall effect for vortices and skyrmions on periodic pinning arrays

Reichhardt, C.

doi:10.1140/epjb/s10051-022-00404-y

Cited by 1 publication

(1 citation statement)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We note that in their simulation work, Cha and Fertig found that at T = 0 there is a critical disorder strength σ c for the 2D crystal to disorder; however, they did not consider the effect of finite temperature to see whether there might still be a reentrant thermally reordered phase. Reentrant phases have been observed previously at zero temperature in systems with periodic pinning [20][21][22][23], but such reentrance is produced by very different mechanisms from what we consider in this work, where the reentrance arises due to the thermal fluctuations creating what is essentially a floating solid phase.…”

Section: Introductionmentioning

confidence: 48%

Melting, reentrant ordering and peak effect for Wigner crystals with quenched and thermal disorder

Reichhardt

Reichhardt²

2023

New J. Phys.

Self Cite

View full text Add to dashboard Cite

We consider simulations of Wigner crystals in solid state systems interacting with random quenched disorder in the presence of thermal fluctuations. When quenched disorder is absent, there is a well defined melting temperature determined by the proliferation of topological defects, while for zero temperature, there is a critical quenched disorder strength above which topological defects proliferate. When both thermal and quenched disorder are present, these effects compete, and the thermal fluctuations can reduce the effectiveness of the quenched disorder, leading to a reentrant ordered phase in agreement with the predictions of Nelson [Phys. Rev. B 27, 2902 (1983)]. There are two competing theories for the low temperature behavior, and our simulations show that both capture aspects of the actual response. The critical disorder strength separating ordered from disordered states remains finite as the temperature goes to zero, as predicted by Cha and Fertig [Phys. Rev. Lett. 74, 4867 (1995)], instead of dropping to zero as predicted by Nelson. At the same time, the critical disorder strength decreases with decreasing temperature, as predicted by Nelson, instead of remaining constant, as predicted by Cha and Fertig. The onset of the reentrant phase can be deduced based on changes in the transport response, where the reentrant ordering appears as an increase in the mobility or the occurrence of a depinning transition. We also find that when the system is in the ordered state and thermally melts, there is an increase in the effective damping or pinning. This produces a drop in the electron mobility that is similar to the peak effect phenomenon found in superconducting vortices, where thermal effects soften the lattice or break down its elasticity, allowing the particles to better adjust their positions to take full advantage of the quenched disorder.

show abstract

Section: Introductionmentioning

confidence: 48%