Modification of structural and magnetic properties of Zn0.96 Mn0.04O samples by Li3+ ion irradiation

TL;DR

This study investigates how 50 MeV Li+3 ion irradiation modifies the structural and magnetic properties of Zn0.96Mn0.04O samples, revealing increased ferromagnetism and impurity phase dissolution, with implications for magnetic material tuning.

Contribution

It demonstrates that ion irradiation can enhance ferromagnetism and alter structural properties in Mn-doped ZnO, introducing a controllable method for magnetic property modification.

Findings

Impurity phase disappears after irradiation.

Saturation magnetization increases with irradiation.

Ferromagnetism is mainly intrinsic, with minor superparamagnetic contributions.

Abstract

Zn0.96Mn0.04O samples were synthesized by solid state reaction technique to explore their magnetic behavior. Structural, morphological and magnetic properties of the samples have been found to be modified by 50 MeV Li+3 ion beam irradiation. The samples exhibit impurity phase and upon irradiation it disappears. Rietveld refinement analysis indicates that substitutional incorporation of Mn in the host lattice increases with irradiation. Grain size decreases with irradiation. Field dependent magnetization (M-H) measurement explicitly indicates ferromagnetic (FM) nature. It has been established from temperature dependent magnetization (M-T) measurement (500 Oe) and ac susceptibility (\chi-T) measurement that ferromagnetism in the system seems to be mainly intrinsic; though superparamagnetic Mn nanoparticles also has a minor role. The analysis of M-T data at comparatively high field (5000-Oe) provides an estimation of antiferromagnetic (AFM) exchange, which acts as a reducing agent for observed magnetic moment. The value of saturation magnetization has been increased upon irradiation and is highly correlated with dissolution of impurity phase. Actually structural property has been modified with ion irradiation and this modification may cause some definite positive change in magnetic property.