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Identification of chirality of chiral multifold fermions in anti-crystals

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 نشر من قبل Yan Sun
 تاريخ النشر 2020
  مجال البحث فيزياء
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The chirality of chiral multifold fermions in reciprocal space is related to the chirality of the crystal lattice structure in real space. In this work, we propose a strategy to detect and identify opposite-chirality multifold fermions in nonmagnetic systems by means of second-order optical transports. The chiral crystals are related by an inversion operation and cannot overlap with each other by any experimental operation, and the chiral multifold fermions in the crystals host opposite chiralities for a given k-point. A change of chirality is indicated by a sign change of the second-order charge current dominated by chiral fermions. This strategy is effective to study the relationship between chiralities in reciprocal and real spaces by utilizing bulk transport.

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