Advancing quantum transport theory for 2D-topological electronics: from quantum matter to emerging devices*

This talk concerns quantum transport theory aided explorations on translating topological quantum matter into viable emerging device paradigms.  First, we present a realizable device design for an all-electrical robust topological valley filter that utilizes spin-protected topological kink states hosted on monolayer 2D-Xene materials with large intrinsic spin-orbit coupling. We elucidate the role of spin-orbit coupling in achieving an improved valley filter performance with a perfect quantum of conductance attributed to the topologically protected kink states. We further elaborate clearly the right choice of material, device geometry and other factors that need to be considered for such a functionality. Crucially, we elucidate how gating techniques can be utilized toward realizing “on-demand” topological symmetry protection. We then extend these ideas to propose a topological quantum field-effect transistor (TQFET) that can potentially be engineered to enable sub-thermionic transistor operation coupled with dissipationless ON-state conduction. We finally discuss the applications toward understanding many recent experiments in the rapidly emerging field of spin-valley qubits in bilayer graphene quantum dots.