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Magnon gravitomagnetoelectric effect in noncentrosymmetric antiferromagnetic insulators

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 نشر من قبل Atsuo Shitade
 تاريخ النشر 2019
  مجال البحث فيزياء
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We study the magnon contribution to the gravitomagnetoelectric (gravito-ME) effect, in which the magnetization is induced by a temperature gradient, in noncentrosymmetric antiferromagnetic insulators. This phenomenon is totally different from the ME effect, because the temperature gradient is coupled to magnons but an electric field is not. We derive a general formula of the gravito-ME susceptibility in terms of magnon wave functions and find that a difference in $g$ factors of magnetic ions is crucial. We also apply our formula to a specific model. Although the obtained gravito-ME susceptibility is small, we discuss several ways to enhance this phenomenon.



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