Nanoscale angular lattice formed by light with high orbital angular

Abstract

Standing waves generated by the interference of Laguerre-Gaussian (LG) beams can be used for dipole trap. We propose a scheme to create a nanometer (nm) scale ring lattice based on the interference of two high order LG beams without decrease the wavelength. Both of the two LG beams have a monocyclic intensity distribution, and they have the same orbital angular momentum (OAM) quantum number on the order of $10^6$. We are able to theoretically demonstrate a dipole potential along angular direction with the period of $\sim$1 nm , given the waist of the Gaussian beams to be $\sim$0.8 $\mu$m. The atoms in this lattice can be trapped along the radial and azimuthal direction in the potential wells of with $\sim$100 nm and $\sim$0.85 nm distance. The proposed method opens up a convenient pathway towards sub-wavelength atom traps that could directly lead to overlap of wave function of atoms in adjacent wells and the formation of molecular bonds.