For laser science, one major goal is to achieve full control over the spatial, temporal and polarization properties of light, and to learn how to precisely manipulate these properties. A property of light is called the Orbital Angular Momentum (OAM), that depends on the spatial distribution of the phase (or crests) of a donut-shaped light beam. More recently, a new variant of OAM was discovered – called the spatial-temporal OAM (ST-OAM), with much more elusive properties, since the phase/crests of light evolve both temporally and spatially. In a collaboration led by senior scientist Dr. Chen-Ting Liao, working with graduate student Guan Gui and JILA Fellows Margaret Murnane and Henry Kapteyn, the team explored how such beams change after propagating through nonlinear crystals that can change their color…
