A Josephson qubit is designed via the application of a tensile strain to a
topological insulator surface sandwiched between two s-wave superconductors.
The strain applied leads to a shift in the Dirac point without changing the
pre-existing conducting states, on the surface of a topological insulator.
Strain applied can be tuned to form a π junction in such a structure.
Combining two such junctions in a ring architecture leads to the ground state
of the ring being in doubly degenerate state- the "0" and "1" states of a
qubit. A qubit designed this way is quite easily controlled via the tunable
strain applied. We report on the conditions necessary to design such a qubit.
Finally the operating time of a single qubit phase gate is derived.Comment: 8 pages and 8 figures with supplementary materia
