# Vortex phases and glassy dynamics in the highly anisotropic superconductor HgBa$_{2}$CuO$_{4+δ}$

Eley, Serena; Willa, Roland; Chan, Mun K.; Bauer, Eric D.; Civale, Leonardo

##### Abstract:
We present an extensive study of vortex dynamics in a high-quality single crystal of HgBa$_{2}$CuO$_{4+δ}$, a highly anisotropic superconductor that is a model system for studying the effects of anisotropy. From magnetization M measurements over a wide range of temperatures T and fields H, we construct a detailed vortex phase diagram. We find that the temperature-dependent vortex penetration field H$_{p}$(T), second magnetization peak H$_{smp}$(T), and irreversibility field H$_{irr}$(T) all decay exponentially at low temperatures and exhibit an abrupt change in behavior at high temperatures T/Tc >~ 0.5. By measuring the rates of thermally activated vortex motion (creep) S(T, H) = |dlnM(T, H)/dlnt|, we reveal glassy behavior involving collective creep of bundles of 2D pancake vortices as well as temperature- and time-tuned crossovers from elastic (collective) dynamics to plastic flow. Based on the creep results, we show that the second magnetization peak coincides with the elastic-to-plastic crossover at low T, yet the mechanism changes at higher temperatures.

 Zugehörige Institution(en) am KIT Institut für Theorie der Kondensierten Materie (TKM) Publikationstyp Zeitschriftenaufsatz Publikationsmonat/-jahr 12.2020 Sprache Englisch Identifikator ISSN: 2045-2322 KITopen-ID: 1000122308 Erschienen in Scientific reports Verlag Nature Research Band 10 Heft 1 Seiten Art.Nr. 10239 Vorab online veröffentlicht am 24.06.2020 Nachgewiesen in DimensionsWeb of ScienceScopus
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