ELFT HÍRADÓ

[Szeminárium koordinátor <sem-admin AT szfki.hu>]

SZFI SeminarHalász GáborOak Ridge National LaboratoryTheory of the Kitaev 
model in a [111] magnetic fieldTuesday, 25 May 2021, 14:00, Teams,  
https://teams.microsoft.com/l/meetup-join/19%3ace423c05cd1543ab9f9905886590ad69%40thread.tacv2/1621439949723?context=%7b%22Tid%22%3a%224d7ddeef-14ff-4911-8c11-401c69384d77%22%2c%22Oid%22%3a%22969d2d4a-5ba8-43f1-bd69-93f0998b025f%22%7dRecent
 numerical studies indicate that the antiferromagnetic Kitaev honeycomb 
lattice model undergoes a magnetic-field-induced quantum phase transition 
into a new spin-liquid phase. This intermediate-field phase has been 
previously characterized as a gapless spin liquid. By implementing a recently 
developed variational approach based on the exact fractionalized excitations 
of the zero-field model, we demonstrate that the field-induced spin liquid is 
gapped and belongs to Kitaev's 16-fold way. Specifically, the low-field 
non-Abelian liquid with Chern number C=±1 transitions into an Abelian liquid 
with C=±4. The critical field and the field-dependent behaviors of key 
physical quantities are in good quantitative agreement with published 
numerical results. Furthermore, we derive an effective field theory for the 
field-induced critical point which readily explains the ostensibly gapless 
nature of the intermediate-field spin liquid. Minden érdeklődőt szívesen 
látunk! - Everyone is welcome to attend.Róbert Juhászsem-admin AT szfki.hu