Effect of Dipolar Interactions on the Spin-Wave Spectrum of a Cubic Antiferromagnet
نویسندگان
چکیده
The effect of dipolar interactions on the spin-wave spectrum of a cubic antiferromagnet is studied. The spinwave spectrum is found to consist of two branches whose frequencies are (ħω)2=(gβ)2[HA+HEa2k2][HA+HE(2−a2k2)−8πM/3+8πM sin2∂k]
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