Electrical and magnetic transport study on strain driven ferromagnetic insulating thin film of low doped manganite

TL;DR

This study investigates how strain influences the electrical and magnetic transport properties of a low-doped manganite thin film, revealing enhanced ferromagnetic insulating states and significant magnetoresistance effects compared to bulk crystals.

Contribution

It demonstrates strain-induced ferromagnetic insulating states in thin films and compares their transport properties with bulk crystals, highlighting differences in transition temperatures and magnetoresistance.

Findings

Increased ferromagnetic insulating temperature (TFMI) and localization length due to strain.

Magnetoresistance varies from 20% to 75% under magnetic fields.

The film exhibits anisotropic magnetoresistance up to 20% depending on field direction.

Abstract

In this paper we have created a strain driven single crystal like ferromagnetic insulating (FMI) state in a PLD grown thin film of low doped LCMO(X = 0.15)on NGO(100) substrate and make a thorough study of strain effects on the electric and magnetic transport of this film. We have studied and compared the FMI state, ferromagnetic transition temperature (TC), ferromagnetic insulating temperature (TFMI) and the resistivity of the film in details with bulk single crystals of X=0.18 to 0.22 doping region. We have found that TFMI and the localisation length of the carriers are increased and there is also a decrease in the Coulomb gap. The magneto transport behavior of the film also differs from the bulk single crystals and the magnetoresistance of the sample is nearly 20 to 75% with the application of the applied field(0 to 10 T) and it falls up to 5 to 40% below a certain temperature and the TC of the film increases to higher temperature with the increasing field. The film also shows anisotropic magnetoresistance as large as 20% depending on applied magnetic field direction.