Temperature Dependence of the Intensity of Magnon Sidebands in Cubic Antiferromagnetic Manganese Compounds

Abstract

The anomalously high intensity and its temperature dependence of the optical absorption in MnO and MnS corresponding to the transitions ⁶A_1g → ⁴T_1g and ⁶A_1g → ⁴T_2g of the Mn²⁺ ion are explained in terms of sidebands associated with magnons. For the calculation of the temperature dependence of the intensity, two models are adopted, one the pair approximation and the other the spin wave approximation. Calculated results are in good agreement with observation.