  Three-dimensional topological insulators represent a new class of materials
in which transport is governed by Dirac surface states while the bulk remains
insulating. Due to helical spin polarization of the surface states, the
coupling of a 3D topological insulator to a nearby superconductor is expected
to generate unconventional proximity induced $p$-wave superconductivity. We
report here on the development and measurements of SQUIDs on the surface of
strained HgTe, a 3D topological insulator, as a potential tool to investigate
this effect.
