Longitudinally engineered metasurfaces for 3D vectorial holography

Vectorial optical fields: recent advances and future prospects

Polarization singularity beams (PSB) possess specific topological structures and exhibit stability and resistance to interference during propagation. These characteristics bestow vector optical fields (VOFs) with unique physical properties and enhanced degrees of manipulation, offering potential application in optical microfabrication, optical micromanipulation, and optical information processing. Within this study, an experimental generation and detection system for VOFs is introduced. Leveraging the technique of dynamically loading holograms onto a spatial light modulator and using a movable measurement platform, it can achieve the basic generation, manipulation, and detection of PSBs. Specifically tailored for college-level physics education, this system enables undergraduates to understand the fundamental principles of VOF generation. Using PSBs as representatives of VOFs and incorporating hands-on experiments on generating and controlling these beams, students can not only master theoretical concepts but also enhance their practical skills in experimental design, instrument operation, and data analysis.

Investigation of the exactness of Reynolds similarity

Compact vectorial optical field generator based on a 10-megapixel resolution liquid crystal spatial light modulator

We present a vectorial optical field (VOF) framework that surpasses the diffraction limit in both long-range imaging and energy delivery. By jointly engineering spatial and temporal dimensions, reflective Fourier ptychography is extended to 3.2 km with 0.37× the classical diffraction limit, while a single-photon LiDAR tomography system achieves centimeter-scale, sub-diffraction imaging at 3.3 km using superconducting nanowire single-photon detectors. These advances demonstrate super-resolution, turbulence-resilient imaging over kilometer-range distances. Beyond super-resolution optical, high power VOFs are able to counteract thermal blooming during atmospheric laser propagation, enhancing on-target power density by a factor larger than 2. Together, these results may outline a cross-scale paradigm that links high-power vector-field structuring, single-photon detection, and adaptive control—offering a pathway toward next-generation optical systems that integrate imaging, sensing, communication and directed energy within a common physical framework.

Generation of vectorial optical fields with complex spatial distribution in the cross section is of great interest in areas where exotic optical fields are desired, including particle manipulation, optical nanofabrication, beam shaping and optical imaging. In this work, a vectorial optical field generator capable of creating arbitrarily complex beam cross section is designed, built and tested. Based on two reflective phase-only liquid crystal spatial light modulators, this generator is capable of controlling all the parameters of the spatial distributions of an optical field, including the phase, amplitude and polarization (ellipticity and orientation) on a pixel-by-pixel basis. Various optical fields containing phase, amplitude and/or polarization modulations are successfully generated and tested using Stokes parameter measurement to demonstrate the capability and versatility of this optical field generator.

We propose a vectorial optical field generation system based on two-dimensional blazed grating to high-efficiently generate structured optical fields with prescribed amplitude, phase, and polarization. In this system, an optimized blazed grating hologram is written on a spatial light modulator (SLM) and can diffract the majority of the incident light into the first-order diffractions of the x and y directions, which then serve as base vectors for synthesizing desired vector beams. Compared with the conventional cosine grating used in the previous work, the proposed two-dimensional, blazed grating has a much higher efficiency. Both computer simulation and optical experiment validate that a conversion efficiency up to 5 times that of the former work is achieved. Our method can facilitate applications of the optical field manipulation.

Emission spectra and excitation temperature spatial profiles, within laser-induced plasmas from solid copper targets, are characterized as a function of laser power density with the use of time-integrated emission spectroscopy. This research shows how the measured axial spatial emission intensity of the expanding plasma can be influenced by the time integration. The excitation temperatures calculated from these integrated emission-line intensities may not coincide with the actual temperature spatial profile. Transient plasma dynamics during time-integrated intensity measurements can influence both the excitation temperature and the atomic number density of the emitting species. As a demonstration of the influence of fluid dynamics on time-integrated emission measurements, a shock-wave model was used as an example to show how the spatial emission intensity profile of a laser-induced plasma can be affected by transient expansion. Even for time-resolved emission measurements, the high velocity of a laser-induced plasma can influence spatial intensity data close to the target surface. The ability to accurately measure spatial emission intensity and temperature behavior is shown to be related to the integration time vs. plasma expansion velocity.

Here we report our recent experimental progresses in optical quantum information processing. In particular, the following topics are included. First, we extend the heralding scheme to multi-mode states and demonstrate heralded creation of qutrit states. Next, we demonstrate storage of single-photon states and synchronized release of them. Then, we demonstrate real-time acquisition of quadrature values of heralded states by making use of an exponentially rising shape of wave-packets. Finally, we demonstrate cluster states in an arbitrarily long chain in the longitudinal direction.

We discuss the diffraction properties and the applications to optical computing and information processing based on anisotropic diffraction in a normal-cut BaTiO3. The formula of diffraction efficiency under Bragg mismatch is derived. It fits well to the experimental results. We also discuss some applications, including optical digital logic operations, optical interconnections, matrix-matrix multiplexing, central-symmetric filters and incoherent-to- coherent optical converters.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Recent advances in electro-optics have brought into use communication and information theory to analyze performance in coherent and incoherent optical information processing systems. An optical information processsing system can be analyzed with many of the same concepts of linear system theory (e.g., spatial impulse response, spatial frequency and spatial domain synthesis, etc.), and the photographic images to be processed can be regarded in the same manner as time signals (e.g., spatial frequency content, spatial amplitude and phase modulation, space-bandwidth product, etc.). Both coherent and incoherent optical processing systems can be treated as linear systems, and the processing operation can generally be carried out by communication theory concepts. Although coherent optical information processing operations have been used for performing complex amplitude operations, complex processing can also be performed with incoherent or white-light illumination. The importance of optical information processing operations, either coherent or incoherent, is due to the basic Fourier transform properties of lenses. In this paper, we will discuss mostly the incoherent systems because they are of more recent interest and possess certain advantages, we feel, over the traditional coherent optical processors. Experimental illustrations of the results are provided. In view of the broad area in optical processing of photographic images, we will confine ourselves to a few applications that we consider of general interest. We apologize for the omission of other techniques and applications, and for neglecting the inclusion of their references.

Chiral organic materials have garnered significant interest in nanophononics due to their ability to manipulate polarized light and encode optical information. Herein, chiral one‐dimensional (1D) organic microplates based on benzocyclazine form homochiral crystals that exhibit excellent optical waveguiding properties. These microplates exhibited highly asymmetric light propagation that depends on the handedness of circularly polarized light (CPL). These homochiral microplates demonstrated selective transmission, with R‐microplate favouring left‐handed CPL and S‐microplate favouring right‐handed CPL, showcasing distinct optical loss coefficients for each enantiomer. Multichannel light propagation was observed, where the intensity varied based on the excitation position. These results highlight the potential of 1D chiral microplates for advanced nanophotonic devices, offering chiral‐dependent control over light transmission for future applications in optical information processing.

We present in principle and demonstrate experimentally a new kind of vector fields: elliptic-symmetry vector optical fields. This is a significant development in vector fields, as this breaks the cylindrical symmetry and enriches the family of vector fields. Due to the presence of an additional degrees of freedom, which is the interval between the foci in the elliptic coordinate system, the elliptic-symmetry vector fields are more flexible than the cylindrical vector fields for controlling the spatial structure of polarization and for engineering the focusing fields. The elliptic-symmetry vector fields can find many specific applications from optical trapping to optical machining and so on.

Photonic skyrmion and meron lattices are structured light fields with topologically protected textures, analogous to magnetic skyrmions and merons. In this talk, I report the theoretical existence of mixed skyrmion and meron quasicrystals in an evanescent optical field. Topological quasiperiodic tilings of even and odd point group symmetries are demonstrated in both the electric field and spin angular momentum. These quasicrystals contain both skyrmions and merons of Néel-type topology, marking the first demonstration of quasiperiodic tilings of such quasiparticles in a three-dimensional vector field. These results are in agreement with the observations of quasiperiodic arrangements of carbon nanoparticles in water driven by ultrasound, and pave the way towards engineering hybrid topological states of light, which may have potential applications in optical manipulation, metrology and information processing.

The introduction of advanced optical materials into communication technology facilitates increased data trans-mission speed, increased bandwidth, intrinsic low crosstalk and high security in multiplexed systems, and simplified implementation of parallel processing. Prototype and first-generation optical communication, information storage and information processing systems have been developed from hybrid electro-optical or all-optical effects in inorganic crystals and semiconductors. Organic and polymer nonlinear optical materials may have processing or performance ad-vantages in the next generation of optical information systems design, but research is needed to define the materials of interest and development will be necessary to incorporate these new materials into practical active elements. This paper is an overview of 3M's program for development of nonlinear optical materials.