Nernst Effect of stripe ordering La${}_{1.8-x}$Eu${}_{0.2}$Sr${}_x$CuO${}_4$

Abstract

We investigate the transport properties of La${}_{1.8-x}$Eu${}_{0.2}$Sr${}_x$CuO${}_4$ ($x=0.04$, 0.08, 0.125, 0.15, 0.2) with a special focus on the Nernst effect in the normal state. Various anomalous features are present in the data. For $x=0.125$ and 0.15 a kink-like anomaly is present in the vicinity of the onset of charge stripe order in the LTT phase, suggestive of enhanced positive quasiparticle Nernst response in the stripe ordered phase. At higher temperature, all doping levels except $x=0.2$ exhibit a further kink anomaly in the LTO phase which cannot unambiguously be related to stripe order. Moreover, a direct comparison between the Nernst coefficients of stripe ordering La${}_{1.8-x}$Eu${}_{0.2}$Sr${}_x$CuO${}_4$ and superconducting La${}_{2-x}$Sr${}_x$CuO${}_4$ at the doping levels $x=0.125$ and $x=0.15$ reveals only weak differences. Our findings make high demands on any scenario interpreting the Nernst response in hole-doped cuprates.