Strong Spin-Orbit Coupled Systems

Strong spin-orbit interactions (SOIs) in materials containing relatively heavy elements such as Bi, Te, Se, etc. are responsible for a great variety of interesting physical phenomena.

A new state of matter, for example, has been identified in so-called topological insulators. The SOI is responsible for protected, conducting surface states of generally bulk-insulating systems. Sometimes similar effects can occur in the bulk. For example, in some non-centrosymmetric semiconductors like BiTeI/BiTeCl, there is a strong Rashba band-splitting of the spin up and spin down bands. The strong spin-polarization in this material class provides a new playground for the field of spintronics, where a controlled manipulation of the spin degree of freedom is desired to enable future applications.

In our lab we are investigating new materials that are promising candidates for new physics related to strong SOI.

LS2146_Bi2Te3_CdBiTeI 

Strong spin-orbit coupling combined with broken inversion symmetry result in exotic topological properties in the electronic ground state of this system.

HHseriesLi2IrO3

Strong spin-orbit coupling and strong correlations lead to a number of exotic ground states in this system. It is closely related to the Kitaev honeycomb systems.