Highly efficient light trapping of metallic microstructures inducedby femtosecond lasers

摘要

Microstructuring of NiTi alloy plates by 800 nm femtosecond lasers is investigated through the line-scribing experimentin ambient air. It is found that some distinct surface structures can be generated by varying laser pulse energies and thescan speeds of the samples. Very weak stray light is detected when He-Ne laser beam is directed on the micro-structuredtargets. The integrated reflectance measurements reveal that the light trapping of these structured metal surfaces can beimproved greatly, even up to 90%, within a large spectral range covering the ultraviolet, the visible and the mid-infrared.It is expected that this result could have great potential applications in the designing of efficient energy transfer devices.