Fabrication of efficient microaxicon by direct electron-beam lithography for long nondiffracting distance of Bessel beams for optical manipulation

We demonstrate a fabrication technique in the realization of microaxicon by single-step processing via electron-beam lithography. Microaxicon is used for the generation of propagation-invariant Bessel beams which find tremendous applications in optical trapping. The proposed technique is a simple, reliable, and reproducible method for the production of high-quality Bessel beams with long propagation-invariant distances, in our configuration, in excess of 20cm. Such Bessel beams with long nondiffracting distances are essential for optical tweezers systems in many cases.