Figure 6.

Topology enhancement effect. (a) Vector plot of the Berry curvature of Weyl semimetals in momentum space. (b) The integrand of the effective third-order optical conductivity tensor is shown along contours of fixed electron energy in momentum space (k_x–k_y) for TaIrTe₄. (c) Optical microscopy image of the device. (d) Light-power dependence of the photocurrent at 4 μm incident wavelength in a FET based on TaIrTe4, a type-II Weyl semimetal. Reproduced with permission from [82,83].Copyright Nature Publishing Group, 2016, 2020.