Spin transport in antiferromagnetic insulators: progress and challenges

Spin transport is the key process for the operation of spin-based devices, which has been the focus of the spintronics research in the last two decades. Conductive materials such as semiconductors and metals, in which the spin transport relies on electron diffusion, were employed as the channels for spin transport in most studies. Due to the absence of conduction electron, insulators were excluded from the candidates for spin current channel before 2010. However, since the demonstration of the spin transmission through ferromagnetic insulator, it was realized that insulators with magnetic ordering can also serve as channels for spin transport. In this talk I would like to introduce our recent progress of spin transport in antiferromagnetic insulators, e.g., the observations of temperature dependence of spin transmission, and spin current switching. I would like to discuss the challenges for developing the functionality of antiferromagnetic insulator as well.