Enhanced charge density wave with mobile superconducting vortices in La$_{1.885}$Sr$_{0.115}$CuO$_4$

TL;DR

This study reveals that in La$_{1.885}$Sr$_{0.115}$CuO$_4$, charge density waves are strongly coupled to superconducting vortices, with magnetic fields enhancing CDW amplitude and indicating complex interplay between different orders.

Contribution

The paper demonstrates the link between enhanced charge density waves and mobile superconducting vortices in a cuprate, revealing new insights into their intertwined nature under magnetic fields.

Findings

CDW exhibits two distinct phases coexisting with superconductivity and SDW.

High magnetic fields induce a sudden increase in CDW amplitude.

Strong coupling between CDW and mobile vortices across the phase diagram.

Abstract

Superconductivity in the cuprates is found to be intertwined with charge and spin density waves. Determining the interactions between the different types of order is crucial for understanding these important materials. Here, we elucidate the role of the charge density wave (CDW) in the prototypical cuprate La$_{1.885}$Sr$_{0.115}$CuO$_4$, by studying the effects of large magnetic fields ($H$) up to 24 Tesla. At low temperatures ($T$), the observed CDW peaks reveal two distinct regions in the material: a majority phase with short-range CDW coexisting with superconductivity, and a minority phase with longer-range CDW coexisting with static spin density wave (SDW). With increasing magnetic field, the CDW first grows smoothly in a manner similar to the SDW. However, at high fields we discover a sudden increase in the CDW amplitude upon entering the vortex-liquid state. Our results signify strong coupling of the CDW to mobile superconducting vortices and link enhanced CDW amplitude with local superconducting pairing across the $H-T$ phase diagram.