Iso-propagation vortices with OAM-independent size and divergence toward future faster optical communications

Recognized in the 1990s,vortex beams'ability to carry orbital angular momentum(OAM)has significantly contributed to applications in optical manipulation and high-dimensional classical and quantum information communication.However,inherent diffraction in free space results in the inevitable expansion of beam size and divergence contingent upon the OAM,limiting vortex beams'applicability in areas such as spatial mode multiplexing communication,fiber-optic data transmission,and particle manipulation.These domains necessitate vortex beams with OAM-independent propagation characteristics.We introduce iso-propagation vortices(IPVs),vortex beams characterized by OAM-independent propagation behavior,achieved through precise radial index configuration of Laguerre-Gaussian beams.IPVs display notable transmission dynamics,including a reduced quality factor,resilience post-damage,and decreased and uniform modal scattering under atmospheric turbulence.Their distinctive attributes render IPVs valuable for potential applications in imaging,microscopy,optical communication,metrology,quantum information processing,and light-matter interactions.Notably,within optical communication,the case study suggests that the IPV basis,due to its OAM-independent propagation behavior,provides access to a more extensive spectrum of data channels compared with conventional spatial multiplexing techniques,consequently augmenting information capacity.

Dual-curvilinear beam enabled tunable manipulation of high-and low-refractive-index particles

We present an innovative approach for the simultaneous agile manipulation of high-refractive-index(HRI) and low-refractive-index(LRI) particles. Our method involves introducing a dual-curvilinear optical vortex beam(DC-OVB) generated by superimposing a pair of curved beams: HRI and LRI particles are controlled by the bright curve and the dark channel between the two curves, respectively. The proposed DC-OVB provides customizable motion paths and velocities for both LRI and HRI particles. Each curve of the DC-OVB can support a distinct orbital flow density(OFD), enabling the application of torques to HRI and LRI particles, guiding them to orbit along specified trajectories and prompting them to execute various curvilinear motions simultaneously,including curvilinear movement, revolution, and rotation.

Manipulating propagation and evolution of polarization singularities in composite Bessel-like fields

Structured optical fields embedded with polarization singularities(PSs)have attracted extensive attention due to their capability to retain topological invariance during propagation.Many advances in PS research have been made over the past 20 years in the areas of mathematical description,generation and detection technologies,propagation dynamics,and applications.However,one of the most crucial and difficult tasks continues to be manipulating PSs with multiple degrees of freedom,especially in three-dimensional(3D)tailored optical fields.We propose and demonstrate the longitudinal PS lines obtained by superimposing Bessel-like modes with orthogonal polarization states on composite vector optical fields(VOFs).The embedded PSs in the fields can be manipulated to propagate robustly along arbitrary trajectories,or to annihilate,revive,and transform each other at on-demand positions in 3D space,allowing complex PS’topological morphology and intensity patterns to be flexibly customized.Our findings could spur further research into singular optics and help with applications such as micromanipulation,microstructure fabrication,and optical encryption.