Srivastava group demonstrates optical initialization and read-out of single electron spin polarization in two-dimensional materials

Ajit Srivastava

Emory Group (left to right): Graduate students Weijie Li and Xiaotong Chen, Professor Ajit Srivastava, and postdoc, Jin Lu (Sudipta Dubey, not shown).  


Individual, localized electron spins in the solid state are a promising system for applications in quantum information science and quantum sensing.  A fundamental challenge is to control and couple the spins in a scalable way.  Professor Ajit Srivastava and coworkers at Emory, in collaboration with researchers at Nanyang Technical University in Singapore, demonstrate an important step in overcoming these hurdles:  the first-time optical initialization of a single spin in a two-dimensional material.  This feat is achieved by using circularly polarized light to selectively excite spins rendered chiral by the spin-valley interaction in atomically-thin transition metal dichalcogenides. These materials can also be manipulated to trap and localize the spins.


Optical initialization of a single spin-valley in charged WSe2 quantum dots, Xin Lu, Xiaotong Chen, Sudipta Dubey, Qiang Yao, Weije Li, Xingzhi Wang, Qihua Xiong and Ajit Srivastava, Nature Nanotechnology 14, 426-431 (2019).