Chen Boqu, Sun Xiaoyu, Li Xiaoxuan, Cai Lu, Zhao Ding, Du Kaikai, Pan Meiyan, Qiu Min
College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou, 310007, China.
Zhejiang Key Laboratory of 3D Micro/Nano Fabrication and Characterization, School of Engineering, Westlake University, 18 Shilongshan Road, Hangzhou, 310030, China.
Adv Mater. 2025 Jan;37(3):e2412414. doi: 10.1002/adma.202412414. Epub 2024 Nov 19.
Enhancing energy density and efficiency in laser processing hinges on precise beam focusing, yet this often causes severe heat absorption and focus shifts in optical lenses. Traditional cooling methods increase cost and complexity, severely limiting versatility. Here, monolithic silicon carbide (SiC) metalens is introduced, which shows unparalleled thermal stability, integrated with a high-power laser. This metalens achieves diffraction-limited focusing with a numerical aperture (NA) of 0.5 and a focal length of 1 cm. Under a 1030 nm pulsed laser at 15 W for 1 h, it shows a minimal temperature rise of 3.2 °C and a tiny focal shift of 14 µm (0.1% relative), only 6% of the shift in conventional lenses. When used to cut a 4H-SiC substrate with the same laser, the metalens exhibit only an 11.4% change in cutting depth after 1 h of operation, correlating with the focal shift results. The results unveil a groundbreaking class of compact SiC photonics devices nearly impervious to heat absorption, representing a monumental leap for high-power laser systems and opening new horizons for their applications and efficiency.
提高激光加工中的能量密度和效率取决于精确的光束聚焦，但这通常会导致光学透镜中严重的热吸收和焦点偏移。传统的冷却方法会增加成本和复杂性，严重限制了其通用性。在此，引入了单片碳化硅（SiC）超构透镜，它具有无与伦比的热稳定性，并与高功率激光集成。这种超构透镜实现了数值孔径（NA）为0.5、焦距为1厘米的衍射极限聚焦。在1030纳米、15瓦的脉冲激光下照射1小时，其温度升高最小为3.2°C，焦点偏移极小，仅为14微米（相对0.1%），仅为传统透镜偏移量的6%。当使用同一激光切割4H-SiC衬底时，超构透镜在运行1小时后切割深度仅变化11.4%，这与焦点偏移结果相关。这些结果揭示了一类具有开创性的紧凑型SiC光子器件，几乎不受热吸收影响，这代表着高功率激光系统的巨大飞跃，并为其应用和效率开辟了新的前景。
