Source and Localization of the PT-Symmetric Terahertz Photoconductivity in Topological Hg1-x Cdx Te – Based Heterostructures

We have shown that in heterostructures based on the topological phase Hg
1-x
Cd
x
Te, the properties of two-dimensional topological states formed at the trivial buffer - topological film heterointerface differ from the states at the topological film - vacuum interface, and it is the former that are responsible for the appearance of PT-symmetric photoconductivity. It has been shown that the source of nonequilibrium electrons is the film bulk, while the place of manifestation of the effect is the trivial buffer - topological film heterointerface.