Abstract:
The planar diffractive lens in zone plate-type configuration plays important roles in the modern optical system, especially in the advanced optical imaging system. Most of them are constructed with opaque metal or dielectric materials with a high refractive index, which restricts the integration possibility for the miniaturized photonic systems. In this work, we proposed and experimentally demonstrated an atomic thin Fresnel zone plate device with 2D semiconductor material. Based on the loss-assisted phase modulation mechanism, an extraordinary phase modulation capability in the entire visible region has been achieved by an atomic thin MoS
2 sheet. By utilizing the femtosecond laser scribing technique, a binary phase Fresnel zone plate has been fabricated on the atomic thin MoS
2 sheet. The diffraction-limited focusing property in broadband has been demonstrated in simulation and experiments. Combining with the direct bandgap property of the monolayer MoS
2 material, this phenomenon may pave the road for the integrated optical system.