  Optical control of structural and electronic properties of Weyl semimetals
allows development of switchable and dissipationless topological devices at the
ultrafast scale. An unexpected orbitial-selective photoexcitation in type-II
Weyl material WTe2 is reported under linearly polarized light (LPL), inducing
striking transitions among several topologically-distinct phases. The symmetry
features of atomic orbitals comprising the Weyl bands result in asymmetric
electronic transitions near the Weyl points, and in turn an anisotropic
response of interlayer shear motion with respect to linear light polarization,
when a near-infrared laser pulse is applied. Consequently, not only
annihilation of Weyl quasiparticle pairs, but also increasing separation of
Weyl points can be achieved, complementing existing experimental observations.
Our results provide a new perspective on manipulating the singularity of Weyl
nodes and coherent control of electron and lattice quantum dynamics
simultaneously.
