  Valleytronics is a research field utilizing a valley degree of freedom of
electrons for information processing and storage. A strong valley polarization
is critical for realistic valleytronic applications. Here, we predict a
tunneling valley Hall effect (TVHE) driven by tilted Dirac fermions in
all-in-one tunnel junctions based on a two-dimensional (2D) valley material.
Different doping of the electrode and spacer regions in these tunnel junctions
results in momentum filtering of the tunneling Dirac fermions, generating a
strong transverse valley Hall current dependent on the Dirac-cone tilting.
Using the parameters of an existing 2D valley material, we demonstrate that
such a TVHE is much stronger than that induced by the intrinsic Berry curvature
mechanism reported previously. Finally, we predict that resonant tunneling can
occur in a tunnel junction with properly engineered device parameters such as
the spacer width and transport direction, providing significant enhancement of
the valley Hall angle. Our work opens a new approach to generate valley
polarization in realistic valleytronic systems.
