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Quantum spin liquids are fascinating phases in quantum magnetism. Broad theoretical advances, and fast progress in materials science have significantly advanced the field in recent years. After a general introduction to the subject, I will talk about the projective symmetry group approach to the problem of classification of such exotic phases. In a second part, I will present work on the theory for the kapellasite material, a spin S=1/2 Heisenberg antiferromagnet on the kagome lattice. Finally, I will discuss a highly intriguing phase that was recently characterized in the triangular spin S=1 compound BaNiSbO. SB et al, PRB 93, 094437 (2016). SB et al, PRB 92, 060407(R) (2015). B. Fak, SB, et al, arXiv:1610.03753 (2016).

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Samuel Bieri, ETH Zurich / Sorbonne
Seminar Room 0.03, ETP
Contact: Simon Trebst