  Tunneling transport across the p-n-p junction of Weyl semimetal with tilted
energy dispersion is investigated. We report that the electrons around
different valleys experience opposite direction refractions at the barrier
interface when the energy dispersion is tilted along one of the transverse
directions. Chirality dependent refractions at the barrier interface polarize
the Weyl fermions in angle-space according to their valley index. A real
magnetic barrier configuration is used to select allowed transmission angles,
which results in electrically controllable and switchable valley polarization.
Our findings may pave the way for experimental investigation of valley
polarization, as well as valleytronic and electron optic applications in Weyl
semimetals.
