- 标题
- 摘要
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- 实验方案
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Optomechanically induced transparency under the influence of spin ensemble system
摘要： Optomechanics is a growing research field, which has received a great attention in the last decade both theoretically and experimentally. In this paper, we theoretically study the opto-mechanically induced transparency with spins coupled to the cavity field, while the cavity filed is driven by external strong coupling and weak probe fields. We analytically calculated the dynamics, as well as the transmissivity of the optomechanical system. The transmission is also examined and discussed. Moreover, the detailed behavior of the transmission shows well the optomechanical induced transparency (OMIT). The paper also show that the OMIT behaviors are strongly affected by the coupling between the spin ensemble and cavity field, as well as the spin decay rate.
关键词： Quantum optics,Optics,Quantum optomechanics
更新于2025-09-04 15:30:14
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Deformable Surface Accommodating Intraocular Lens: Second Generation Prototype Design Methodology and Testing
摘要： Purpose: Present an analysis methodology for developing and evaluating accommodating intraocular lenses incorporating a deformable interface. Methods: The next generation design of extruded gel interface intraocular lens is presented. A prototype based upon similar previously in vivo proven design was tested with measurements of actuation force, lens power, interface contour, optical transfer function, and visual Strehl ratio. Prototype verified mathematical models were used to optimize optical and mechanical design parameters to maximize the image quality and minimize the required force to accommodate. Results: The prototype lens produced adequate image quality with the available physiologic accommodating force. The iterative mathematical modeling based upon the prototype yielded maximized optical and mechanical performance through maximum allowable gel thickness to extrusion diameter ratio, maximum feasible refractive index change at the interface, and minimum gel material properties in Poisson’s ratio and Young’s modulus. Conclusions: The design prototype performed well. It operated within the physiologic constraints of the human eye including the force available for full accommodative amplitude using the eye’s natural focusing feedback, while maintaining image quality in the space available. The parameters that optimized optical and mechanical performance were delineated as those, which minimize both asphericity and actuation pressure. The design parameters outlined herein can be used as a template to maximize the performance of a deformable interface intraocular lens.
关键词： physiological optics,accommodation,lens,cataract surgery,optics
更新于2025-09-04 15:30:14
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RECTANGULAR WAVE BEAM BASED GO/PO METHOD FOR RCS SIMULATION OF COMPLEX TARGET
摘要： The rectangular wave beams-based geometrical optics (GO) and physical optics (PO) hybrid method is applied to the radar cross section (RCS) simulation of complex target. In the implementation process, the incident wave beam is divided into plenty of regular rectangular wave beams. The RCS of target is subsequently harvested from the sum of the contributions from rectangular wave beams. And Open Graphics Library (OpenGL) is used to accelerate ray tracing for the GO/PO method. Here, each pixel corresponds to a rectangular wave beam, which improves the defect that the pixel number should be larger than the patch number on the model and the e?ciency in the general OpenGL based GO/PO method. In addition, the patch size in the presented method can be arbitrary as long as the model is described accurately with these patches. The simulation results prove this point and show that the proposed rectangular wave beam-based GO/PO method is feasible and can keep a high calculation accuracy and e?ciency with a low pixel number.
关键词： ray tracing,geometrical optics,OpenGL,rectangular wave beams,radar cross section,physical optics
更新于2025-09-04 15:30:14
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45.1: <i>Invited Paper:</i> Formulation of Jones matrix for the general reflective birefringent medium
摘要： We have formulated the Jones matrix for the general reflective birefringent medium and derived an expression of the intensity reflectivity for the general reflective birefringent medium with a single polarizer. Two examples are illustrated to show how one can use them in real cases.
关键词： liquid crystal,Jones matrix,liquid crystal display,reflective TN cell,intensity reflectivity,optics,reflective display,birefringent,polarization
更新于2025-09-04 15:30:14
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High order perfect optical vortex shaping
摘要： We proposed a method based on high-order Bessel–Gaussian beam to improve quality and intensity profile of high-order perfect optical vortex (POV) array under tight focusing condition. By using this method, parameters of POV could be controlled such as uniform ring width, adjustable ring diameter as well as controllable position, numbers and topological charges. A quality factor was proposed for assessing POV with different ring diameter and different topological charge. Comparing with the conventional method for generating POV, the optimal high-order POV carry uniform intensity distribution and the same ring width and diameter, which may enlarge the application on optical manipulation of multiple particles, large capacity optical storage and multiplexing optical vortex communication.
关键词： Tight focusing,Optics vortex,Phase modulation
更新于2025-09-04 15:30:14
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High-contrast imaging in polychromatic light with the self-coherent camera
摘要： Context. In the context of direct imaging of exoplanets, coronagraphs are commonly proposed to reach the required very high contrast levels. However, wavefront aberrations induce speckles in their focal plane and limit their performance. Aims.An active correction of these wavefront aberrations using a deformable mirror upstream of the coronagraph is mandatory. These aberrations need to be calibrated and focal-plane wavefront-sensing techniques in the science channel are being developed. One of these is the self-coherent camera, of which we present the latest laboratory results. Methods. We present here an enhancement of the method: we directly minimized the complex amplitude of the speckle ?eld in the focal plane. Laboratory tests using a four-quadrant phase-mask coronagraph and a 32 × 32 actuator deformable mirror were conducted in monochromatic light and in polychromatic light for di?erent bandwidths. Results. We obtain contrast levels in the focal plane in monochromatic light better than 3 × 10?8 (RMS) in the 5–12 λ/D region for a correction of both phase and amplitude aberrations. In narrow bands (10 nm) the contrast level is 4 × 10?8 (RMS) in the same region. Conclusions. The contrast level is currently limited by the amplitude aberrations on the bench. We identi?ed several improvements that can be implemented to enhance the performance of our optical bench in monochromatic as well as in polychromatic light.
关键词： instrumentation: adaptive optics,instrumentation: high angular resolution
更新于2025-09-04 15:30:14
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[IEEE 2018 IEEE Research and Applications of Photonics In Defense Conference (RAPID) - Miramar Beach, FL (2018.8.22-2018.8.24)] 2018 IEEE Research and Applications of Photonics In Defense Conference (RAPID) - Integrated Photonics for RF-Photonic Phased-Array Radar System
摘要： We discuss some potential benefits of using integrated RF-photonic devices/circuits in a phased-array-Radar system. A viable and simple solution is proposed for a low-cost, RF-photonic multi-beams beamformer that meets both transmitting and receiving RF-system specifications/requirements. Proof-of-concept experiments and chip-scale integrated-photonics subsystem development will also be discussed.
关键词： Phased array Radar,Fiber optics links and subsystems,Optical control of phased array antenna,Radio frequency photonics,Integrated Photonics
更新于2025-09-04 15:30:14
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Implementation of General Dispersive Anisotropic Materials in Lebedev FDTD
摘要： A finite-difference time-domain (FDTD) algorithm—the Lebedev FDTD method—is augmented to allow for the simulation of electromagnetic waves in general dispersive anisotropic materials. Distinct dispersions may be applied to each of the principal axes of the anisotropic medium. The method is based on the auxiliary differential equation and is simple to implement. Because of the collocated nature of the algorithm, multiterm dispersions necessary in previous implementations are avoided. Lebedev grid has previously been studied in detail by different research groups for the simulation of anisotropy. In this paper, we specifically focus on extending frequency-dispersive materials to this method and provide multiple examples to demonstrate the accuracy, validity, and stability of the method.
关键词： dispersive,Anisotropic,invisibility cloak,finite-difference time-domain (FDTD),transformation optics
更新于2025-09-04 15:30:14
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IMPROVEMENT OF RADIATION CHARACTERISTICS OF BALANCED ANTIPODAL VIVALDI ANTENNA USING TRASFORMATION OPTICS
摘要： Transformation optics is a convenient method to control paths of electromagnetic waves and radiation characteristics of antennas. In this paper, we try to increase the gain of Balanced Antipodal Vivaldi Antenna (BAVA) over 8{16 GHz frequency band using an optical conformal transformation. The proposed antenna can be implemented by ordinary dielectric materials and graded photonic crystals (GPCs). In this designed BAVA, better side-lobe level (SLL) and cross-polarization are achieved compared to a conventional BAVA. Simulation results validate the performance of the design approach.
关键词： graded photonic crystals,Transformation optics,Balanced Antipodal Vivaldi Antenna,cross-polarization,side-lobe level,gain improvement
更新于2025-09-04 15:30:14
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The Monte Carlo Ray-Trace Method in Radiation Heat Transfer and Applied Optics || Fundamentals of Ray Tracing
摘要： A ray is defined as the collection of straight-line path segments followed by an energy bundle from its point of emission to its point of absorption. The definition includes the possibility of intermediate reflection, scattering, refraction, and even diffraction events. Ray tracing involves the application of basic mathematics to the process of identifying the intersection of ray segments with surfaces. Most engineering and science students acquire the required mathematical tools long before they enter university. The current chapter provides a review of the mathematical principles governing ray tracing and the related issues of meshing and indexing.
关键词： Monte Carlo Method,Radiation Heat Transfer,Applied Optics,Mathematical Principles,Ray Tracing
更新于2025-09-04 15:30:14