High‐Dimensional Chiral Transfer by Bilaterally Encircling Exceptional Points

Abstract In a non‐Hermitian system, dynamically encircling exceptional points (EPs) within the parameter space facilitates chiral mode transfer, wherein the resulting output states are contingent upon the encircling EP direction. However, mainstream two‐stage EP‐based chiral mode transfer has encountered critical bottlenecks, as current research primarily focuses on operating within a single dimension (polarization or mode). Here, high‐dimensional chiral transfer by bi‐directionally encircling EPs is presented, which implements distinct chiral transfers for different polarizations. Consequently, the high‐dimensional chiral transfer yields unconventional output mode states that are influenced not only by the injection direction but also by the polarization state. Meanwhile, leveraging the birefringence effect of the silicon waveguide, high‐performance high‐dimensional chiral transfer is experimentally demonstrated using the bi‐directionally encircling‐EP approach, which demonstrates robustness against encircling loop selection. Moreover, the occurrence of chiral transfer can also be controlled by polarization. The findings not only pave the way for further exploration of high‐dimensional non‐Hermitian systems but also unlock opportunities for a wide variety of high‐capacity applications.