Superlative Spin Transport in Two-Dimensional Black Phosphorus

Exploitation of the intrinsic spin of an electron, spintronics, facilitates the development of multifunctional and novel devices which could play an important role in the Beyond-CMOS era. Two-dimensional (2D) crystals and their van der Waals heterostructures are particularly promising for spintronics device applications due to their unique properties, including strong responses to field effect gating and proximity interactions, which may enable new functionalities that are not possible with conventional bulk materials [1].<br/><br/>Two-dimensional black phosphorus is a promising material for semiconducting spintronics research due to its high charge mobilities, low atomic mass, and puckered crystalline structure, which are expected to lead to anisotropic spin transport with nanosecond spin-lifetimes. In this presentation, I will introduce ultra-thin BP as a unique platform for studying rich spin-dependent physics. Firstly, I will show that BP supports all electrical spin injection, transport, precession and detection up to room temperature [2]. Then, I will present our recent findings on the impact of the unique crystal structure of BP on its spin dynamics, revealing strong anisotropic spin transport along three orthogonal axes [3]. Finally, a van der Waals bonded spintronics device utilizing BP as channel material and 2D magnets for spin injection/detection will be introduced. The exceptional spin transport and strong spin-lifetime anisotropy we observe in BP add to the growing body of evidence for the potential of 2D materials in functional spin-based device applications.<br/><br/>[1] A. Avsar et al., Rev. Mod. Phys. 92, 021003 (2020)<br/>[2] A. Avsar et al., Nat. Phys. 13, 888-894 (2017)<br/>[3] L. Cording et al., Nat. Mater. (In press)