Chiral electromagnetic near field of polaritons in two-dimensional anisotropic materials

Chiral electromagnetic near fields, which are vital for chiral sensing, photochemistry, and photoemitters, are typically derived from the chiral configurations of plasmonic materials. This often necessitates complex structural engineering. In this study, we illustrate that polaritons in two-dimensional (2D) anisotropic materials can generate chiral near fields, thus eliminating the need for intricate structural designs. The near field on either side of the 2D material is single handed, with both sides exhibiting contrasting optical chirality. The scattering of the 2D material's edges to the polaritons enhances the dissymmetry factor that could be three orders of magnitude higher than that of circularly polarized light. Our research offers an innovative strategy to creating chiral near fields.