We found that the optical vortex could fabricate anano-scaled metal needle (nano-needle). Opticalvortices, having a helical (twisted) wavefront owing toa phase singularity, carry an angular momentum. Theangular momentum of the optical vortices istransferred to the melted (or vaporized) metal duringablation process, resulting in the formation of thenano-needle. The tip curvature of the nano-needle witha height of 8.4 ?m was measured to be ＜50nm,corresponding to less than one-twentieth of the laserwavelength (1064nm). We also demonstrated thefabrication of a two-dimensional 5 × 5 nanoneedlearray. The direction of the nano-needle could be alsocontrolled by changing an incident angle of the opticalvortex onto the metal target.
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