Raman study of stoichiometric and Zn-doped ${\mathrm{Fe}}_3{\mathrm{O}}_4$

We report here our Raman studies on ${\mathrm{Fe}}_{3-x}{\mathrm{Zn}}_x{\mathrm{O}}_4\mathrm{}(x=0,0.015,0.03\mathrm{})\mathrm{}$ across the Verwey transition in the temperature range 20–300 K. The changes in Raman spectra as a function of doping show that the changes are gradual for samples with higher Zn doping. Allen’s formula has been used to estimate the strength of electron-phonon interaction from the observed lineshape parameters. These estimates show that there is strong electron-phonon coupling in this system and is highest for the $T_{2g}^3$ mode in comparison to $A_{1g}$ and $T_{2g}^2$ modes.