  Uniaxial strain affects pairing symmetry states in superconductors by
changing the lattice symmetry, and by altering Fermi surface topology. Here, we
present a systematic study of these effects within a one-band negative-U
Hubbard model for s, p and d-wave pairing states. We consider a general 2D
model that can be applied to superconductors under uniaxial strain, modelled
via hopping anisotropy, on a square lattice. The results presented here model
an in plane compression along the x-axis, which reduces the lattice symmetry
from a tetragonal to an orthorhombic crystal space group. The effects of
hopping anisotropy on the different types of gap pairings are explored. We show
that changes in Tc are tunable with hopping anisotropy and depend on the
orientation of the gap function in relation to the opening of the Fermi surface
during the Lifshitz transition. In comparing the model results to experimental
data for the case of Sr2RuO4 it is found that both the d + id and d + ig
pairings best describe the changes in Tc for the superconducting state in
regards to its response to small uniaxial strain.
