Planar Hall and Nernst effect in patterned ultrathin film of La0.7Sr0.3MnO3

TL;DR

This study reports the observation of the Planar Nernst Effect and Planar Hall Effect in ultrathin La0.7Sr0.3MnO3 films, demonstrating their ferromagnetic properties and angular dependence at room temperature.

Contribution

It is the first to demonstrate the simultaneous observation of Planar Nernst and Hall effects in ultrathin LSMO films, highlighting their potential for spin caloritronic applications.

Findings

Planar Nernst Effect observed at 5 K temperature difference.

Planar Hall Effect confirmed ferromagnetic nature of the film.

Angular dependence shows four-fold symmetry at 250 K.

Abstract

We present the observation of a transverse thermopower, or Planar Nernst Effect, in patterned ultrathin film (8 nm) of La0.7Sr0.3MnO3 (LSMO) driven by heat current applied in-plane of the film and Planar Hall Effect (PHE) in the same LSMO ultrathin film with in-plane current of 100 microA is also investigated. Even for temperature difference of 5 K the Planar Nernst Effect in ultrathin film (8 nm) shows a coercivity of 3 Oe same as observed in Planar Hall Effect measurement and confirms the ferromagnetic nature of thin film. The angular dependence of transverse voltages shows four-fold sin{theta} cos{theta} dependence symmetry at 250 K, which is consistent with Planar Hall Effect measurement.