Agradecimentos: Two of us (V.S.deC. and E.M.) would like to thank C. Farias for stimulating discussions. They also thank the financial support from FAPESP under Grant No. 2016/05069-7, and the kindly hospitality of the International Institute of Physics (IIP), in Natal, where part of this work was...

Agradecimentos: Two of us (V.S.deC. and E.M.) would like to thank C. Farias for stimulating discussions. They also thank the financial support from FAPESP under Grant No. 2016/05069-7, and the kindly hospitality of the International Institute of Physics (IIP), in Natal, where part of this work was done; IIP is supported by the Brazilian ministries MEC and MCTIC. H.F. acknowledges funding from CNPq under Grant No. 405584/2016-4

Abstract: We investigate the edge magnetism and the spin transport properties of an SU(2)-symmetric Kitaev spin liquid (KSL) model put forward by Yao and Lee [Phys. Rev. Lett. 107, 087205 (2011)] on the honeycomb lattice. In this model, the spin degrees of freedom fractionalize into a Z(2) static...

Abstract: We investigate the edge magnetism and the spin transport properties of an SU(2)-symmetric Kitaev spin liquid (KSL) model put forward by Yao and Lee [Phys. Rev. Lett. 107, 087205 (2011)] on the honeycomb lattice. In this model, the spin degrees of freedom fractionalize into a Z(2) static gauge field and three species of either gapless (Dirac) or gapped (chiral) Majorana fermionic excitations. We find that, when a magnetic field is applied on a zigzag edge, the Dirac KSL exhibits a nonlocal magnetization associated with the existence of zero-energy edge modes. The application of a spin bias V = mu(up arrow) - mu(down arrow) y at the interface of the spin system with a normal metal produces a spin current into the KSL, which depends as a power law on V, in the zero-temperature limit, for both Dirac and chiral KSLs, but with different exponents. Lastly, we study the longitudinal spin Seebeck effect, in which a spin current is driven by the combined action of a magnetic field perpendicular to the plane of the honeycomb lattice and a thermal gradient at the interface of the KSL with a metal. Our results suggest that edge magnetization and spin transport can be used to probe the existence of charge-neutral edge states in quantum spin liquids

FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP

2016/05069-7

CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ

405584/2016-4

Aberto