Date of this Version
PHYSICAL REVIEW APPLIED 5, 031001 (2016). DOI: 10.1103/PhysRevApplied.5.031001
The frequency dependence of the electric-field-induced magneto-optical Faraday effect is investigated in the magnetoelectric antiferromagnet chromia. Two electrically induced Faraday signals superimpose in proportion to the linear magnetoelectric susceptibility α and the antiferromagnetic order parameter η. The relative strength of these contributions is determined by the frequency of the probing light and can be tuned between extreme characteristics following the temperature dependence of α or η. The frequency dependence is analyzed in terms of electric dipole transitions of perturbed Cr3+ crystal-field states. The results allow us to measure voltage-controlled selection, isothermal switching, and temperature dependence of η in a tabletop setup. The voltage-specific Faraday rotation is independent of the sample thickness, making the method scalable and versatile down to the limit of dielectric breakdown.