All-Optical Control of Vortex Lasing in Silicon-Organic Lattices.

This paper reports a silicon-organic hybrid lattice that can lase with vortex emission and allow all-optical control. We combine an array of amorphous silicon nanodisks with gain from dye molecules in organic solvents to generate vortex lasing from bound states in the continuum under pulsed optical pumping. Irradiating the device with an additional continuous wave green laser beam can cause optical heating in silicon and lead to negative change in the refractive index of the organic solvents; meanwhile, the green laser beam can provide additional gain. Dynamic tuning of the lasing wavelength is achieved by varying the intensity of the controlling beam. Furthermore, the vortex beam lasing can be switched to single-lobed beam lasing by moving the controlling spot to break the in-plane symmetry within the pumping spot. Our findings could shed new light on active silicon topological devices.