[4] N. Romming et al. Writing and deleting single magnetic skyrmions. Science, 341, 636-639(2013).
[15] A. Ghosh et al. A topological lattice of plasmonic merons. Appl. Phys. Rev., 8, 041413(2021).
[22] D. S. Simon. Tying Light in Knots, 2053-2571(2018).