摘要： Metamaterials allow control and tailoring the optical response of natural materials to achieve unprecedented functionalities. These artificial electromagnetic media are engineered by structuring materials on a subwavelength scale. Metamaterials have conventionally been made out of noble plasmonic metals. Intrinsically, plasmonic metamaterials suffer from high energy dissipation due to ohmic losses at ultraviolet to visible spectral frequencies. Therefore, in recent years, all-dielectric resonant metamaterials typically made from high-index dielectrics have been explored widely as they can potentially alleviate such losses, while allowing similar functionalities. One of the factors constraining their widespread use is slow and high-cost production techniques required to achieve nanoscale structures across large areas in reasonable timescales. Here we demonstrate that laser direct writing can be used as a viable alternative to FIB and EBL for implementation of optical metasurfaces. Our proposed approach allows manufacturing all-dielectric metasurfaces with flexible geometry and high uniformity at mm2/min throughput rates. Laser direct writing relies on removing the material via irradiation with an intense light source producing a contaminant free nano-patterned surface. The patterning was performed using femtosecond laser pulses with a bandwidth centred at 515 nm (a second harmonic of the Yb:KGW laser). The laser beam was focused with a 0.6 NA objective lens producing a spot size of 430 nm. Optimized experimental conditions allowed us to fabricate arrays of holes directly in free-standing, 50 nm thick SiN membranes, which exhibit strong optical resonances in the visible spectral range. Each perforation is achieved with a single femtosecond laser pulse, providing for an area of 1×1 mm2 to be patterned within 10 minutes. Our writing technique allowed us to inscribe holes with sub-200 nm in diameter, which is well below the diffraction limit. The periods of arrays ranged from 300 to 1000 nm allowing us to achieve optical resonances in the visible with high resonance quality factors up to 46 (for a metasurface period of 520). Quality factor is defined here as Q = λR/Δλ, where λR is the reflection resonance wavelength and Δλ is the half-maximum linewidth). The asymmetry in the structure, which leads to polarization dependent resonance, stems from a linearly polarized laser beam resulting in asymmetric intensity distribution at the focal point. Although our proof of principle demonstration is limited to dielectric nanomembranes, this technique can be easily extended to fabrication of metasurfaces in semiconductors and metals due to the nonlinear character of femtosecond laser pulse interaction with materials. In conclusion, we have demonstrated feasibility and versatility of femtosecond laser processing for developing scalable optical metasurfaces.