Spin transport in two-dimensional materials and van der Waals heterostructures

Summary form only given. Two-dimensional (2D) atomic crystals are considered to be very promising for nanoelectronics and spintronics applications. It provides a large class of materials proposed to be important for long distance spin transport, spin polarized tunneling and large spin-orbit coupling. Here I will discuss spintronic aspects of these 2D materials and their heterostructures. Graphene is considered to be an ideal material for spin transport due to the high mobility and long spin lifetime of the carriers. Recently, we demonstrated spin transport over distances of 16 μm and spin lifetimes up to 1.2 ns in large area CVD graphene on SiO2/Si substrate at room temperature [1]. Subsequently, using insulating h-BN as a tunnel barrier on graphene, we observe an enhancement in spin polarized tunneling [2], and its negative sign for thicker h-BN layers [3]. These signatures provide an experimental evidence of the spin filtering across the ferromagnet/hBN-graphene van der Waals heterostructures. We also employed 2D materials such as h-BN and MoS2 in ferromagnetic tunnel junctions for observation of tunnel magnetoresistance up to room temperature [4]. We further aim to address the issue of spin manipulation in graphene by employing heterostructures with other 2D semiconductors [5], topological insulators [6] and materials with novel spin textures. I will present both electronic and spintronic properties of these 2D materials and their heterostructures. These findings open a platform for exploring novel spin functionalities in 2D crystals and understanding the basic phenomenon that control their behavior.