  Underpinning the field of "valleytronics" is the coupling of the helicity of
circularly polarized light to the valley degree of freedom, and this remains
the only known lightform to exhibit this remarkable effect. Here we show that
on femtosecond time scales valley coupling is a much more general effect. We
find that two time separated linearly polarized pulses allow almost complete
control over valley excitation, with the pulse time difference and polarization
vectors emerging as key parameters for valley control. In contrast to the Berry
curvature that underpins the effect for circularly polarized light, we
demonstrate that a different phase structure drives this effect, with
excitations during each linear pulse acquiring a valley discriminating phase
involving the polarisation angle of linear light. Unimportant in a single
linear pulse, for pairs of pulses these can constructively and destructively
interfere. Employing state-of-the-art time dependent density function theory,
we show that the effect is robust to the complexities of charge dynamics in a
real material with the example of a transitional metal dichalcogenide.
