Controlled switching of orbital angular momentum in an optical parametric oscillator

Controlled switching of orbital angular momentum (OAM) of light at practical powers over arbitrary wavelength can have important implications for future quantum and classical systems. Here we report on a single source OAM beams based on an optical parametric oscillator (OPO) that can provide all such capabilities. We demonstrate transfer of OAM modes of any order, jl pj, of pump to the signal and idler in an OPO, to produce jl pj1 OAM states by controlling the relative cavity losses of the resonated beams. As a proof-of-principle, we show when pumping with the OAM states jl pj 1 and jl pj 2 for different relative losses of signal and idler, the OPO two (j1;0i and j0;1i) and three (j2;0i, j1;1i, and j0;2i) output states, respectively. Our findings show that using a loss modulator, one can achieve rapid switching of the OAM mode in OPO output beams in time.