Catenary optics for achromatic generation of perfect optical angular momentum

The catenary is the curve that a free-hanging chain assumes under its own weight, and thought to be a "true mathematical and mechanical form" in architecture by Robert Hooke in the 1670s, with nevertheless no significant phenomena observed in optics. We show that the optical catenary can serve as a unique building block of metasurfaces to produce continuous and linear phase shift covering [0, 2π], a mission that is extremely difficult if not impossible for state-of-the-art technology. Via catenary arrays, planar optical devices are designed and experimentally characterized to generate various kinds of beams carrying orbital angular momentum (OAM). These devices can operate in an ultra-broadband spectrum…

• NR
  National Research Foundation Singapore

  Awards: ID0EAPAK2589, NRF-CRP10-2012-04
• AR
  Australian Research Council

  Awards: FL100100099, ID0ETJAK2588, ID0EGEAK2587, CE 110001018