[理论室学术报告] Skyrmion Lattices in Antiferromagnetic Systems
||Daniel Carlos Cabra
La Plata University
报告摘要： We present the results of a study of the classical antiferromagnetic Heisenberg model on the triangular lattice with Dzyaloshinskii-Moriya interactions in a magnetic field. We focus in particular on the emergence of a composite spin crystal phase, dubbed antiferromagnetic skyrmion lattice, that was recently observed in [Phys. Rev. B 92, 214439 (2015)] for intermediate fields. This complex phase can be made up from three inter-penetrated skyrmion lattices, one for each sub-lattice of the original triangular one. We present our numerical results in detail and the explicit construction of the low-energy effective action that reproduces the correct phenomenology. This effective action could serve as a starting point to study the coupling to charge carriers, lattice vibrations, structural disorder and transport phenomena.