Numerical simulations (CST) of the y-polarized fields, the metasurface is at z = 0. (a) Fields when only the control wave is incident on the structure. The control wave is initially x-polarized (not shown here) from left to right. In the positive z-direction, the control wave is transmitted with a y polarization. In the negative z-direction, the control wave is reflected with a y polarization. (b) Fields when only the signal wave is incident on the metasurface. (c) Combination of control and signal waves, the cancellation of the transmission by destructive interference is clearly visible.