Light beams with optical vortices can propagate in free space only with integer orbital angular momentum. Herein, this scientific consensus theoretically and experimentally is upheaved by proposing light beams carrying natural noninteger orbital angular momentum. These peculiar vortex beams are unique solutions to the Helmholtz equation, which possesses optical vortices with topological charges of l + 0.5, where l is an integer. During propagation in free space, their amplitudes and vortex phases with noninteger topological charges can be maintained stably. The findings of this study provide an alternative state of optical vortices in physics, which can serve as basis for innovations in optics and related scientific fields.

Superposition of two independent orthogonally polarized beams is a conventional principle of creating a new light beam. Herein, it is intended to achieve the inverse process, namely, extracting inherent polarization modes from a single light beam. However, inherent polarization modes within a light beam are always intertwined so that a stable polarization is maintained during propagation in free space. To overcome this limitation, an approach that breaks the modulation symmetry of an m‐order vector vortex beam is reported, thereby unbinding the inherent polarization modes. Using polarization mode competition along with an optical pen, polarization modes within m‐order vector vortex beam are extracted at will in the focal region of an objective lens. This work treats the light beam as a treasure box, and polarization mode extraction is just like the key of the box. Whatever it is, one can just take it directly from the box. This physical thought conveys an entirely new principle of polarization modulation and paves the way for multidimensional manipulation of light fields.

Recently, perfect optical vortexes (POVs) have attracted substantial attention, because they have an orbital angular momentum (OAM) and the beam diameter is independent of the topological charges. There are numerous innovative results that have been found by modulating the POV optical field. However, methods for controlling the arbitrary parameters of POV are lacking. In this paper, we use the optical pen to overcome this problem. The optical pen is a high-precision optical field modulation method construction based on the relationship between the optical path difference and phase. Based on this method, we have achieved POV arrays with controllable arbitrary parameters in free space, including the spatial position, numbers, topological charges, beam diameter, and amplitude. This work can be applied not only in the fields of optical tweezers, particle manipulation, and super-resolution microscopic imaging, but also will promote the development of optical communication, quantum information coding, and so on.

Perfect vortex beams can only propagate stably with integer topological charges. Thus, creating perfect fractional vortex beams capable of stable propagation in free space, as perfect integer vortex beams, is crucial. This study proposed perfect vortex beams carrying fractional topological charge of l + 0.5, which are special solutions of the wave equation, and can maintain stable propagation with physical laws same as integer topological charge. Perfect fractional vortex beams were created in free space, which can break the cognition of traditional fractional perfect vortex beams and promote the development of scientific fields such as optical communication, quantum sensing, and optical imaging.

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