Identifying the quasi-particle contribution to the Nernst effect in La-based cuprates

It has recently been shown that stripe order causes an enhanced normal-state Nernst effect ($\nu = N/B$) in Nd- and Eu-doped La$_{2-x}$Sr$_x$CuO$_4$ (LSCO) [1]. In magnetic fields up to $B=10$~T, the normal-state Nernst effect was tracked down to $\sim30$~K. Here we report on the Nernst effect in Nd-LSCO at $p=0.20$ and Eu-LSCO at $p=0.125$ in fields up to $B=28$~T, where in both cases $T_C<2$~K. In this field-induced normal state, the quasi-particle contribution to the Nernst effect dominates completely over the signal from superconducting fluctuations. We find that $\nu/T$ grows with decreasing temperature to reach a very sizable value as $T\to 0$. \\ \\ {[1]} \quad Cyr-Choini\`ere \textit{et al.}, \textit{Nature}, \textbf{458}, 743--745 (2009).