- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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The Monte Carlo Ray-Trace Method in Radiation Heat Transfer and Applied Optics || Extension of the MCRT Method to Non-Diffuse, Non-Gray Enclosures
摘要： The assumption of diffuse emission and diffuse-specular reflection in gray enclosures is adequate for many applications encountered in engineering practice. This is especially true in the conceptual and preliminary design stages. However, final design and performance studies often require the use of bidirectional surface optical models restricted to a specified wavelength interval. In this chapter we develop the concept of the band-averaged spectral radiation distribution factor, which is the most general tool available for treating radiant exchange among surfaces, but first we learn through extended examples how to compose and use models to simulate the optical behavior of non-diffuse surfaces.
关键词： Monte Carlo Ray-Trace Method,Non-Gray Enclosures,Radiation Heat Transfer,Applied Optics,Bidirectional Spectral Surfaces,Non-Diffuse
更新于2025-09-04 15:30:14
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Quantum imaging with sub-Poissonian light: challenges and perspectives in optical metrology
摘要： Non-classical correlations in optical beams offer the unprecedented opportunity of surpassing conventional limits of sensitivity and resolution in optical measurements and imaging, especially but not only, when a low photon flux down/single photons are measured. We review the principles of quantum imaging and sensing techniques which exploit sub-Poissonian photon statistics and non-classical photon number correlation, presenting some state-of-the-art achievements in the field. These quantum photonics protocols have the potential to trigger major steps in many applications, such as microscopy and biophotonics and represent an important opportunity for a new deal in radiometry and photometry.
关键词： quantum optics,quantum correlation,sub-Poissonian light,Quantum enhanced measurement
更新于2025-09-04 15:30:14
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Redesign of the GANIL GTS ECRIS for 1+/n+ studies
摘要： More than half of the beams produced at GANIL are metallic elements, underlining the importance of their continuing development. Compared to the conventional techniques (oven, sputtering, MIVOC), the 1+/n+ method has demonstrated superior ionization e?ciencies, suggesting the potential for improved metal beam production. Dedicated studies are required to assess the feasibility of this approach. The SPIRAL1 Charge Breeder is now in operation at the GANIL radioactive beam facility SPIRAL1. Operation in high radiation area poses challenges for its future development. A separate test stand supporting charge breeder and metal ion beam R&D is thus desirable. The GTS 14.5 GHz ECRIS has been chosen as a platform for 1+/n+ studies. After the upgrade program of 2017–2018, the GTS provides good performance and versatility, making it well-suited for ion source R&D. A new injection module has been designed for 1+ injection into the GTS plasma to be used in the 1+/n+ studies. It can be easily replaced with the conventional system for normal ion source operation. The design of the new injection system will be presented in detail with ion optical simulations of the 1+ beam injection.
关键词： Ion sources (positive ions, negative ions, electron cyclotron resonance (ECR), electron beam (EBIS),Beam Optics
更新于2025-09-04 15:30:14
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Geometrical optics and geodesics in thin layers
摘要： The propagation of a light ray in a thin layer (film) within geometrical optics is considered. It is assumed that the ray is captured inside the layer due to reflecting walls or total internal reflection (in the case of a dielectric layer). It has been found that for a very thin film (the length scale is imposed by the curvature of the surface at a given point) the equations describing the trajectory of the light beam are reduced to the equation of a geodesic on the limiting curved surface. There have also been found corrections to the trajectory equation resulting from the finite thickness of the film. Numerical calculations performed for a couple of exemplary curved layers (cone, sphere, torus, and catenoid) confirm that for thin layers the light ray which is repeatedly reflected propagates along the curve close to the geodesic but as the layer thickness increases, these trajectories move away from each other. Because the trajectory equations are complicated nonlinear differential equations, their solutions show some chaotic features. Small changes in the initial conditions result in remarkably different trajectories. These chaotic properties become less significant the thinner the layer under consideration.
关键词： thin layers,geometrical optics,light propagation,geodesics,curved surfaces
更新于2025-09-04 15:30:14
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Ultrafast Nonlinear Optical Excitation Behaviors of Mono- and Few-Layer Two Dimensional MoS2
摘要： The layered MoS2 has recently attracted significant attention for its excellent nonlinear optical properties. Here, the ultrafast nonlinear optical (NLO) absorption and excited carrier dynamics of layered MoS2 (monolayer, 3?4 layers, and 6?8 layers) are investigated via Z-scan and transient absorption spectra. Our experimental results reveal that NLO absorption coefficients of these MoS2 increase from ?27 × 103 cm/GW with more layers at 400-nm laser excitation, while the values decrease from 2.0 × 103 cm/GW at 800 nm. In addition, at high pump fluence, when the NLO response occurs, the results show that not only the reformation of the excitonic bands, but also the recovery time of NLO response decreases from 150 ps to 100 ps with an increasing number of layers, while the reductive energy of A excitonic band decreases from 191.7 meV to 51.1 meV. The intriguing NLO response of MoS2 provides excellent potentials for the next-generation optoelectronic and photonic devices.
关键词： ultrafast photonic devices,Ultrafast optics,two-dimensional materials
更新于2025-09-04 15:30:14
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Multiphoton Tomography with Linear Optics and Photon Counting
摘要： Determining an unknown quantum state from an ensemble of identical systems is a fundamental, yet experimentally demanding, task in quantum science. Here we study the number of measurement bases needed to fully characterize an arbitrary multimode state containing a definite number of photons, or an arbitrary mixture of such states. We show this task can be achieved using only linear optics and photon counting, which yield a practical though nonuniversal set of projective measurements. We derive the minimum number of measurement settings required and numerically show that this lower bound is saturated with random linear optics configurations, such as when the corresponding unitary transformation is Haar random. Furthermore, we show that for N photons, any unitary 2N design can be used to derive an analytical, though nonoptimal, state reconstruction protocol.
关键词： photon counting,linear optics,quantum state tomography,multiphoton states,quantum information
更新于2025-09-04 15:30:14
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Operational Resource Theory of Continuous-Variable Nonclassicality
摘要： Genuinely quantum states of a harmonic oscillator may be distinguished from their classical counterparts by the Glauber-Sudarshan P representation—a state lacking a positive P function is said to be nonclassical. In this paper, we propose a general operational framework for studying nonclassicality as a resource in networks of passive linear elements and measurements with feed forward. Within this setting, we define new measures of nonclassicality based on the quantum fluctuations of quadratures, as well as the quantum Fisher information of quadrature displacements. These measures lead to fundamental constraints on the manipulation of nonclassicality, especially its concentration into subsystems, that apply to generic multimode non-Gaussian states. Special cases of our framework include no-go results in the concentration of squeezing and a complete hierarchy of nonclassicality for single-mode Gaussian states.
关键词： Optics,Quantum Physics,Quantum Information
更新于2025-09-04 15:30:14
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Two-photon self-Kerr nonlinearities for quantum computing and quantum optics
摘要： The self-Kerr interaction is an optical nonlinearity that produces a phase shift proportional to the square of the number of photons in the field. At present, many proposals use nonlinearities to generate photon-photon interactions. For propagating fields these interactions result in undesirable features such as spectral correlation between the photons. Here we engineer a discrete network composed of cross-Kerr interaction regions to simulate a self-Kerr medium. The medium has effective long-range interactions implemented in a physically local way. We compute the one- and two-photon S matrices for fields propagating in this medium. From these scattering matrices we show that our proposal leads to a high-fidelity photon-photon gate. In the limit where the number of nodes in the network tends to infinity, the medium approximates a perfect self-Kerr interaction in the one- and two-photon regime.
关键词： quantum computing,quantum optics,photon-photon gate,cross-Kerr interaction,self-Kerr interaction
更新于2025-09-04 15:30:14
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Toward New Engagement Paradigms For Intraocular Lenses: Light-Initiated Bonding of Capsular Bag to Lens Materials
摘要： Successful implantation of accommodating intraocular lenses (A-IOL), require firm engagement of the IOL haptics to the capsular bag. We evaluated the use of photochemical bonding to engage IOL materials to the capsular bag.
关键词： physiological optics,lens capsule,A-IOLs,photobonding
更新于2025-09-04 15:30:14
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[OSA CLEO: QELS_Fundamental Science - San Jose, California (2015..-..)] CLEO: 2015 - Nonlinear Frequency Mixing in a Surface Nanoscale Axial Photonics Resonator
摘要： We report on four-wave mixing in a simple-to-fabricate surface nanoscale axial photonics resonator (SNAPR) obtained by pumping with two spectral modes while exploiting a self-locked pump scheme.
关键词： Microcavities,Nonlinear optics, four-wave mixing
更新于2025-09-04 15:30:14