Spin transport and spin pump in graphene-like materials: effects of tilted Dirac cone

We study spin transport phenomena in two-dimensional graphene-like materials in the presence of arbitrarily tilted Dirac cones. We use the generalized scattering approach to calculate the spin current in normal-ferromagnetic-normal (N-F-N) junction of the materials. The tilting of the Dirac cone strongly influence the transport properties and hence the spin conductance. We find a reversal of spin current polarization with smooth variation of the tilt parameter. We also study the spin current by the adiabatic precession of a doped ferromagnet on top of the material. It is shown that spin-mixing conductance and hence spin current become zero for a finite value of tilt. These findings provide an efficient way towards high controllability of spin transport of the ferromagnetic junction and can be very useful in the field of spintronics. Depending on the character of spin transport properties, it is also possible to measure the tilt of the Dirac cone.