  In this work, we propose mono/few layers of MgTe (110) facets of zinc-blende
structure for a unique next-generation ferromagnet-free nonballistic spin-field
effect transistor. The atomic arrangement in this facet exhibits a unique
combination of three basic symmetries found in nature: rotation, reflection,
and translation. The electronic properties based on the density functional
theory (DFT) reveal momentum-independent unidirectional spin polarization known
as persistent spin texture (PST) that leads to an infinite spin lifetime in
this particular facet. PST in these 2D structures originating from crystal
symmetry makes them an ideal alternative to quantum well structures. Although
the proposed Datta-Das s-FET is applicable to nonballistic s-FET, there has
been little technological progress in this rapidly growing field of research
and only a trivial amount of 2D semiconductors have been identified that
exhibit PST intrinsically. In this regard, this particular facet studied in
this work will be a great asset. A detailed theoretical insight into the origin
of PST and its application in a ferromagnet-free s-FET has been proposed
combining both the spin-Hall effect and inverse spin-Hall effects, harmonizing
spintronics with conventional electronics.
