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Time-resolved optical observation of spin-wave dynamics

J. S. Dodge·A. B. Schumacher·D. S. Chemla·N. Ingle·M. R. Beasley
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Abstract

We have created a nonequilibrium population of antiferromagnetic spin-waves in Cr2O3, and characterized its dynamics, using frequency- and time-resolved nonlinear optical spectroscopy of the exciton-magnon transition. We observe a time-dependent pump-probe line shape, which results from excitation induced renormalization of the spin-wave band structure. We present a model that reproduces the basic characteristics of the data, in which we postulate the optical nonlinearity to be dominated by interactions with long-wavelength spin-waves, and the dynamics to be due to spin-wave thermalization.

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J. S. Dodge, A. B. Schumacher, D. S. Chemla, N. Ingle, M. R. Beasley. 1999-11-18. Time-resolved optical observation of spin-wave dynamics. https://doi.org/10.1103/physrevlett.83.4650

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