In data transmission, spatially distinguishable channels and optical vector vortex beams provide additional degrees of freedom. Although several coherent light sources carrying topological singularities have been reported, developing a universal strategy for ultra small, high-quality photonic nanocavities for designing, generating, and supporting optical vortex modes remains highly challenging.
Recently, Min Soo Hwang, Ha Re em Kim, Hong Gyu Park, and others from Seoul National University and Yuri Kivshar from The Australian National University published a paper in Nature Photonics, reporting a wavelength scale, low threshold, vortex and anti vortex nanolaser, mainly in the C5 symmetric optical cavity formed by topological discord.
By utilizing the similarity between tight binding models and optical simulations, various photon spin off cavities were designed and analyzed. In these cavities, unique resonance modes are strongly confined and exhibit a wavelength scale mode volume, thereby retaining topological charges in the spinoff geometry. In the experiment, optical vortices of laser modes were identified by measuring polarization resolved images, Stokes parameters, and self interference patterns. A vortex nanolaser based on a simple design program will pave the way for the next generation of optical communication systems.
Figure 1: Design strategy of photon spin off cavity.
Figure 2: Corresponding relationship of angular momentum in tight binding method TB calculation and optical simulation.
Figure 3: Simulating optical vortex and anti vortex modes in a C5 symmetric photon spin off cavity.
Figure 4: Experimental vortex and anti vortex nanolasers.
Figure 5: Evidence of vortex and anti vortex modes.
Editor: Sichuan Jinzhongde Science and Technology Research Institute
Source: High functional film
