  We study the electron scattering produced by local out-of-plane strain
deformations in the form of Gaussian bumps in graphene. Of special interest is
to take into account the scalar field associated with the redistribution of
charge due to deformations, and in the same footing as the pseudomagnetic
field. Working with the Born approximation approach we show analytically that
even when a relatively small scalar field is considered, a rather strong valley
asymmetric scattering could arise as a function of the energy and angle of
incidence. In addition, we find that the valley polarization can reverse its
sign as the incident energy is increased. These behaviors are totally absent if
the scalar field is neglected. These results are supported by quantum dynamical
simulations of electron wave packets. Results for the average trajectories of
wave packets in locally strained graphene clearly show focusing and beam
splitting effects enhanced by the presence of the scalar field that can be of
interest in the implementation of valleytronic devices.
