Here we will present a reliable (experimentally and numerically proved) technique for multi-spot pattern formation in the focus of a lens (i.e. in the artificial far field). This was done using large square-shaped and/or hexagonal optical vortex (OV) lattices generated by spatial light modulators. Experimental and numerical results showing a controllable far-field beam reshaping when such lattices are generated in the Fourier plane will be discussed. Even more interesting bright structures can be obtained by combining OV lattices (of any type) with different node spacings. We show that the small-scale structure of the observed patterns results from the OV lattice with the larger array node spacing, whereas the large-scale structure stems from the OV lattice with the smaller array node spacing. The orientation of the mixed far-field structures is proven to rotate by 180° when all TCs are inverted.

Date Published: 30 December 2019
PDF: 9 pages
Proc. SPIE 11332, International Conference on Quantum, Nonlinear, and Nanophotonics 2019 (ICQNN 2019), 113320J (30 December 2019); doi: 10.1117/12.2554013

Published in SPIE Proceedings Vol. 11332:
International Conference on Quantum, Nonlinear, and Nanophotonics 2019 (ICQNN 2019)
Alexander A. Dreischuh; Tony Spassov; Isabelle Staude; Dragomir N. Neshev, Editor(s)