Tunable electrical and magnetic properties of half-metallic ZnxFe3−xO4 from first principles

Abstract

The electrical and magnetic properties of Zn-doped Fe(3)O(4) at different doping concentrations of Zn have been investigated using a density functional method with generalized-gradient approximation corrected for on-site Coulombic interactions. The electronic structure calculation predicts that Zn(x)Fe(3-x)O(4) (0 ≤x≤ 0.875) is half-metallic with a full spin polarization. The hopping carrier concentration of Zn(x)Fe(3-x)O(4) decreases with increasing x, which indicates a distinct increase in the resistivity. The saturation magnetization of Zn(x)Fe(3-x)O(4) increases evidently with increasing x from x = 0 to x = 0.75 (i.e. from 4.0 to 8.3 μ(B)/f.u.) and then decreases rapidly to zero at x = 1. The robust half-metallicity, large tunability of electrical and magnetic properties of a Zn doped Fe(3)O(4) system make it a promising functional material for spintronic applications.

Impact of inversion and non-stoichiometry on the transport properties of mixed zinc-cobalt ferrites

“…The absence of mixed valence states prohibits electron hopping, consequently rendering truly stoichiometric ZnFe 2 O 4 an insulator. 42 However, electronic conductivity arises in ZnFe 2 O 4+l , if the ferrite exhibits even a small degree non-stoichiometry l o 0, i.e., an oxygen deficiency. The release of oxygen inherently results in the formation of Fe 2+ B sites to preserve charge neutrality.…”

Effect of Zn substitution in (111)-textured ZnxFe3−xO4 thin films on magnetization dynamics

“…Zn x Fe 3x O 4 as a tunable ferromagnetic semiconductor has received considerable attention due to its strong electron correlation and high Curie temperature [1][2][3]. More desirably, low concentration of Zn substitution is an effective method for tuning the electronic and magnetic properties of Fe 3 O 4 over a wide range without changing the half metallic properties [4,5]. These merits make Zn x Fe 3x O 4 system a promising functional material for spintronic devices such as spin-polarized current injection and tunneling magnetoresistance [6,7].…”

“…Recently, Jedrecy et al [9] presented a detailed magnetic and magnetotransport investigation of textured Zn x Fe 3x O 4 thin films grown on various substrates. In addition, theoretical analyses were also given with tunable electrical and magnetic properties of half-metallic Zn x Fe 3x O 4 by Cheng et al [5]. On the other hand, the dynamic magnetic properties such as magnetic anisotropy and magnetization damping of Zn x Fe 3x O 4 thin films are less reported may be related to the difficulty of the ultrafast dynamic characterization.…”

Structural, dielectric and magnetic investigations on Al3+substituted Zn-ferrospinels

“…3 Moreover, advanced applications oen require materials with magnetic properties that can be deliberately tuned by external control parameters. 4,5 The wide range of applications for ferrites is attributed to their resistivity, low eddy current losses, high Curie temperature, magnetocrystalline anisotropy, reasonable cost and excellent chemical stability. 6 In nanocrystalline phase magnetic, structural and electrical properties of ferrites change drastically in comparison to their bulk counterpart.…”

“…It has been demonstrated by several experimental results that the A-site Zn 2+ ions substitution is an effective method for tuning the physical properties of Fe 3 O 4 . 5 Substitution of Fe 3+ by Al 3+ on B-site in ferrite nanoparticles modies the structural, electrical and magnetic properties of ferrites. 12 The Al 3+ substituted ferrites nd a wide range of practical applications where minimum electrical and magnetic losses are required.…”