Nice physics, but not so sure about the electronic device. The minimum 2 terminal (contact) resistance of the topological FET is h/2e^2 = 12.9 kOhms corresponding to the two propagating modes. The allowed R_external from 2015 ITRS is ~200 Ohms/micron channel width. Low power drive current targets are ~1.5 mA/micron. 1D edge channels are not going to do the job for a FET. But gate controllable topology is very interesting.
"Topological degrees of dynamical freedom as a function of space-time manifold, less that, you land in discontinueties and non smoothness which is topologically doomed
