Effect of stripe order strength for the Nernst effect in La_{2-x}Sr_xCu_4 single crystals

TL;DR

This study investigates how stripe order strength influences the Nernst effect in La_{2-x}Sr_xCuO_4 crystals, revealing that stripe order fluctuations enhance the Nernst signal at high temperatures, while stronger stripe order suppresses it at low temperatures.

Contribution

It provides new insights into the relationship between stripe order and the Nernst effect, highlighting the dual role of stripe fluctuations and static order in superconducting properties.

Findings

Nernst onset temperature remains unchanged with Nd-doping.

Stripe order suppresses the Nernst signal at low temperatures.

Nernst signal increases below the charge order temperature T_{ch}.

Abstract

We have precisely measured the Nernst effect in Nd-doped La$_{2-x}$Sr$_x$CuO$_4$ single crystals with controlling the strength (stability) of the stripe order. We found that the onset temperature $T_{onset}$, where the Nernst signal starts increasing, does not change conspicuously in spite of Nd-doping. At low temperatures, on the other hand, the absolute value of the Nernst signal is strongly suppressed in accordance with the strength of the stripe order. These results imply that the fluctuation of (charge) stripe order enhances the Nernst signal below $T_{onset}$ at high temperatures, and then the stripe order enhanced by Nd-doping suppresses the superconducting fluctuation to reduce the Nernst signal at low temperatures. We also observed an increase of the Nernst signal below the charge order temperature $T_{ch}$ which is observed in diffraction measurement.