Wave motions in nature were known to the ancients, and their mathematical expression in physics today is essentially the same as that first provided by d'Alembert and Euler in the mid-18th century. Yet it was only in 1992 that physicists managed to control a basic property of light waves: their capability of swirling around their own axis of propagation. During the past decade such techniques of control have also been developed for quantum particles: atoms, electrons and neutrons.
I will present a simple description of these phenomena, emphasizing the most basic aspects of wave and quantum particle motion, and showing how these are used in our recent work on twisting neutron wavefunctions .
1. “Controlling Neutron Orbital Angular Momentum,” C. W. Clark, R. Barankov, M. G. Huber, M. Arif, D. G. Cory and D. A. Pushin, Nature 525, 504 (2015)