  The magnetopiezoelectric effect (MPE) is a cross-coupling between an electric
current and strain in metals with neither inversion symmetry nor time-reversal
symmetry. Unlike the conventional piezoelectric effect, the MPE allows a
piezoelectric response in superconductors, as we call the superconducting
piezoelectric effect (SCPE). The SCPE may enable a piezoelectric response
without Joule heating and provide a probe of exotic superconducting symmetry.
In this paper, we propose a formulation of the SCPE and calculate both the MPE
and SCPE in the two-dimensional noncentrosymmetric s-wave superconductor under
an in-plane magnetic field. We find that the magnitude of the SCPE is
comparable to the MPE. It is also clarified that finite total momentum of
Cooper pairs in the helical superconducting state plays a crucial role in the
SCPE.
