We investigate the tunneling valley Hall (TVH) transport in a $n\text{−}i\text{−}n$ junction for two-dimensional tilted Dirac fermions modulated by ac gate voltages. In the static limit, the upper bound of the TVH angle is obtained, which depends only on the parameters of the Dirac cones. In the presence of periodic driving, we derive the TVH conductivity based on the Floquet scattering theory and calculate it numerically by means of the scattering-matrix method. It is found that photon-assisted tunneling at strong driving redistributes the transmission probability among multiple Floquet sidebands. Both the longitudinal and TVH conductivities can be several times larger than their static limits. Due to Floquet-sideband-related Fano resonances, a sideband-resolved transmission can be enhanced at the transverse momentum with a large transverse velocity so that the TVH angle exceeds its static maximum. The Floquet-enhanced TVH response can be tuned and optimized by both the Dirac-cone tilt parameter and the orientation of the $n\text{−}i\text{−}n$ interface relative to the crystalline axes. These findings could be helpful for the Floquet engineering of the TVH effect.

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• Valley degrees of freedom
• Dirac semimetal
• Floquet systems
• S-matrix method in transport
• k dot p method