Giant enhancement of room temperature magnetoresistance in La_{0.67}Sr_{0.33}MnO_{3}/Nd_{0.67}Sr_{0.33}MnO_{3} multilayers

TL;DR

This study demonstrates that ultra-thin La_{0.67}Sr_{0.33}MnO_{3}/Nd_{0.67}Sr_{0.33}MnO_{3} multilayers significantly enhance room temperature magnetoresistance by reducing layer thickness, which increases spin fluctuations.

Contribution

The paper reports a novel approach of using ultra-thin multilayers to drastically increase magnetoresistance near room temperature in manganites.

Findings

150% magnetoresistance at 270 K with 10 Å layers

15% magnetoresistance at 270 K with 40 Å layers

Reduced layer thickness increases spin fluctuations

Abstract

The metal-insulator transition temperature in CMR manganites has been altered and brought close to the room temperature by preparing La$_{0.67}$Sr$_{0.33}$MnO$_{3}$ (LSMO)/ Nd$_{0.67}$Sr$_{0.33}$MnO$_{3}$ (NSMO) multilayers with ultra thin individual layers of LSMO and NSMO. The LSMO/NSMO multilayers with ultra thin individual layers of thickness of about $10\AA$ exhibits 150% magnetoresistance at 270 K whereas LSMO/NSMO multilayers with moderate individual layer thickness of about $40\AA$ each exhibits a mere 15% magnetoresistance at the same temperature. We have shown that the reduction in thickness of the individual layers leads to increased spin fluctuation which results in the enhancement of magnetoresistance.