Regular Article

Nernst effect of stripe ordering La_1.8−xEu_0.2Sr_xCuO₄

C. Hess^1a, E.M. Ahmed^1b, U. Ammerahl², A. Revcolevschi² and B. Büchner¹

¹ IFW-Dresden, Institute for Solid State Research, PO Box 270116, 01171 Dresden, Germany
² Laboratoire de Physico-Chimie de L’État Solide, ICMMO, UMR 8182, Université Paris-Sud, 91405 Orsay Cedex, France

^a e-mail: c.hess@ifw-dresden.de
^b Present address: Solid State Physics Department, National Research Center, Postal Code 12622, Dokki, Cairo, Egypt

Received: 14 July 2010
Revised: 12 August 2010
Published online: 11 October 2010

Abstract

We investigate the transport properties of La_1.8−xEu_0.2Sr_xCuO₄ (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−xEu_0.2Sr_xCuO₄ and superconducting La_2−xSr_xCuO₄ 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.