Topological insulators (TIs), such as Bi₂Te₃ and Bi₂Se₃, are newly discovered quantum materials. TIs are bulk insulators for which strong spin-orbit interaction inverts the orbital character of the conduction and valence bands at the band edges. Two-dimensional TIs are a remarkable class of layered materials, exhibiting unique symmetry-protected helical metallic edge states with an insulating interior. The realization of various exotic quantum phenomena like the quantum anomalous Hall effect (QAHE), which is expected to be important for quantum computing, is rapidly transforming into the development of realistic materials that can be used to build novel quantum devices.

Using this insight, we are applying our wet-chemical synthesis technique to the development of Bi₂Te₃-based 2D TIs such as tetradymite-type compounds with improved critical temperature for QAHE, creating a new starting point in the effort to exploit QAHE via collaboration using a unique natural heterostructure of intralayer ferromagnetic and interlayer antiferromagnetic planes intergrowing with layers of TI materials in the absence of an external magnetic field.

Further reading materials:

J. Phys. Chem. Lett.  8(8), 1905-1919 (2017).    10.1021/acs.jpclett.7b00222                 

J. Am. Chem. Soc., 127(28), 10112 - 10116 (2005).    10.1021/ja052286j