Figure 3.

The topological winding numbers $w_0$ [in panel (a)] and $w_{\pi }$ [in panel (b)] versus the imaginary parts of vertical and diagonal hopping amplitudes $J_y^i$ and $J_d^i$. The other system parameters are set as $(J_x,J_y^r,J_d^r,V)=(0.5\pi ,0.6\pi ,4\pi ,0.1\pi )$. In both panels, each region with a uniform color refers to a Floquet topological phase of the non-Hermitian PQTLL model, with the values of winding numbers $(w_0,w_{\pi })$ shown explicitly in the figure. The lines separating different regions are the boundaries between different non-Hermitian Floquet topological phases, which can be obtained numerically by setting ${\Delta }_0=0$ and ${\Delta }_{\pi }=0$ in Equations (9) and (10).