Interpretation of ferromagnetic Fe doped ZnO by Mössbauer spectroscopy

Abstract

Single phase Zn0.95Fe0.05O sample was obtained by the sol-gel method with annealing at 650°C for 6h in H2 5%/Ar balance gas atmosphere. The crystalline structure of Zn0.95Fe0.05O is determined to be a P63mc hexagonal structure with lattice constants a0=3.255Å and c0=5.207Å at room temperature. The Mössbauer spectra were obtained at various temperatures ranging from 4.2to295K. The values of the isomer shifts (δ) show that for all temperature ranges, they are in the ferrous (Fe2+) state. The magnetic hyperfine field (Hhf) and electric quadrupole splitting (ΔEQ) in the weak ferromagnetic state at 4.2K have been analyzed, yielding the following results: Hhf=37.8kOe, θ=67.5°, φ=0°, η=0.75, ΔEQ=2.06mm∕s, and R=7.4, respectively. From the Mössbauer spectrum at 77K, the paramagnetic quadrupole phase is related to the temperature dependence of spin-lattice relaxation.