BEGIN:VCALENDAR VERSION:2.0 PRODID:Data::ICal 0.22 BEGIN:VEVENT DESCRIPTION:Nirmal Ghimire\, George Mason University\n\n
Materials in condensed matter have r ecently been testbeds for several exotic particles\, predicted but never r ealized\, in high energy physics. The examples are skyrmions observed in m agnetic textures. Weyl fermions in the low energy electronic excitations o f Weyl semimetals and Majorana fermions in topological superconductors. Th ese discoveries have not only allowed access to the fundamental physics of the rare particles but also driven large interest in the application of s uch exotic states to future technologies such as spin based electronics an d quantum computation. Discoveries of topological states in materials have largely benefited from the precision of the electronic structure calculat ions in the weakly correlated systems. In the first part of this talk\, I will discuss our resent results on two such predicted materials &ndash\; 1 ) NbAs\, one of the first generation Weyl semimetals [1-3] and 2) Pd3 Pb\, a novel topological material hosting multiple Dirac points and surface states [4]. While calculations are pretty accurate in weakly corre lated systems\, the topological states in presence of strong electron corr elations are still not well understood. As such\, materials can take a lea d in this field. In the second part of the talk\, I will briefly highlight our recent efforts in this area\, driven by specific materials design cri teria. As an illustration\, I will discuss our study on the chiral-lattice antiferromagnet CoNb3S6 that has topological charac ter in the electronic band structure\, and manifests an unusually large an omalous Hall effect [5].
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\n\n[1] N. J. Ghimire et al. J. Phys.: Condens. Matter 27\, 152201 (2015).
\n\n[2] Y. Luo et al. Phys. Rev. B 92\, 205134 (2015)< /span>
\n\n[3] P. J. W. Moll et al.\, Nat. Communs. 7\, 12492 (2016).
\n\n[4] N. J. Ghimire et al.\, Phys. Rev. Materials 2 \, 081201(R) (2018)
\n\n[5] N. J. Ghimire et al.\ , Nat. Communs. 9\, 3280 (2018)
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\n DTSTART:20180920T150000Z LOCATION:Physics Building\, Room 313 SUMMARY:"A materials-driven approach to the novel topological states of mat ter" END:VEVENT END:VCALENDAR