Growth and physical property study of single nanowire (diameter ~ 45nm) of half doped Manganite

TL;DR

This study reports the growth, elemental analysis, and electrical characterization of 45nm diameter La0.5Sr0.5MnO3 nanowires, demonstrating retention of magnetic transition and similar resistivity behavior to bulk material.

Contribution

It presents a novel hydrothermal synthesis method for single manganite nanowires and confirms their preserved magnetic and electrical properties at nanoscale.

Findings

Nanowires exhibit ferromagnetic transition near bulk TC at 325 K.

Electrical resistivity shows insulating behavior similar to bulk.

Elemental composition remains stable after size reduction.

Abstract

We report here the growth and characterization of functional oxide nanowire of hole doped manganite of La0.5Sr0.5MnO3 (LSMO). We also report four probe electrical resistance measurement of single nanowire of LSMO (diameter ~ 45nm) using FIB fabricated electrodes. The wires were fabricated by hydrothermal method using autoclave at a temperature of 270 oC. The elemental analysis and physical property like electrical resistivity were studied at individual nanowire level. The quantitative determination of Mn valency and elemental mapping of constituent elements was done by using Electron Energy Loss Spectroscopy (EELS) in the Scanning Transmission Electron Microscopy (STEM) mode. We addressed the important issue of whether as a result of size reduction the nanowires can retain the desired composition, structure and physical properties. The nanowires used were found to have a ferromagnetic transition (TC) at around 325 K which is very close to the bulk value of around 330 K found in single crystal of the same composition confirming that the functional behavior is likely to be retained even after size reduction of the nanowires to a diameter of 45 nm. The electrical resistivity shows insulating behavior within the temperature range measured, which is very much similar to the bulk system.