Takei, SoHalperin, BertrandYacoby, AmirTserkovnyak, Yaroslav2015-06-162014Takei, So, Bertrand I. Halperin, Amir Yacoby, and Yaroslav Tserkovnyak. 2014. “Superfluid Spin Transport through Antiferromagnetic Insulators.” Phys. Rev. B 90 (9) (September). doi:10.1103/physrevb.90.094408.1098-0121http://nrs.harvard.edu/urn-3:HUL.InstRepos:16388189A theoretical proposal for realizing and detecting spin supercurrent in an isotropic antiferromagnetic insulator is reported. Superfluid spin transport is achieved by inserting the antiferromagnet between two metallic reservoirs and establishing a spin accumulation in one reservoir such that a spin bias is applied across the magnet. We consider a class of bipartite antiferromagnets with Néel ground states, and temperatures well below the ordering temperature, where spin transport is mediated essentially by the condensate. Landau-Lifshitz and magnetocircuit theories are used to directly relate spin current in different parts of the heterostructure to the spin-mixing conductances characterizing the antiferromagnet∣∣metal interfaces and the antiferromagnet bulk damping parameters, quantities all obtainable from experiments. We study the efficiency of spin angular-momentum transfer at an antiferromagnet∣∣metal interface by developing a microscopic scattering theory for the interface and extracting the spin-mixing conductance for a simple model. Within the model, a quantitative comparison between the spin-mixing conductances obtained for the antiferromagnet∣∣metal and ferromagnet∣∣metal interfaces is made.en-USJournal Article2015-06-1610.1103/physrevb.90.094408