Product Code: ICA12_N503

Nano-Needle Fabrication Based on Optical Vortex Laser Ablation
Authors:
Kohei Toyoda, Graduate School of Advanced Integration Science, Chiba Univ.; Chiba Japan
Katsuhiko Miyamoto, Graduate School of Advanced Integration Science, Chiba Univ.; Chiba Japan
Nobuyuki Aoki, Graduate School of Advanced Integration Science, Chiba Univ.; Chiba Japan
Takashige Omatsu, Graduate School of Advanced Integration Science, Chiba Univ., CREST, Japan Science and Technology Agency; Chiba Japan
Presented at ICALEO 2012

We found that the optical vortex could fabricate a nano-scaled metal needle (nano-needle), for the first time. Optical vortices, having a helical (twisted) wavefront owing to a phase singularity, carry an angular momentum. The angular momentum of the optical vortices was transferred to the melted (or vaporized) metal during ablation process, resulting in the formation of the nano-needle. The tip curvature of the nano-needle with the height of 7.6 µm was measured to be <40nm, corresponding to less than one twenty-fifth of the laser wavelength (1064nm). The direction of the nano-needle could be also controlled by changing an incident angle of the optical vortex onto the metal target.