摘要：“近年来，光子学范畴有越来越多的突破性效果，可是高影响力的期刊仍是太少。”主编Anatoly Zayats教授表明，“Advanced Photoni……检查具体>>
Advanced Photonics 敞开投稿啦！
摘要：中科院上海光机所我国激光杂志社与世界光学工程学会（SPIE）联合发布Advanced Photonics (AP)新刊封面。……检查具体>>
摘要：我国激光杂志社和世界光学工程学会（SPIE）联合兴办新刊：Advanced Photonics ……检查具体>>
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We present a fully automated laser system with low-intensity noise for coherent Raman scattering microscopy. The robust two-color system is pumped by a solid-state oscillator, which provides Stokes pulses fixed at 1043 nm. The tunable pump pulses of 750 to 950 nm are generated by a frequency-doubled fiber-feedback femtosecond optical parametric oscillator. The resulting pulse duration of 1.2 ps provides a viable compromise between optimal coherent Raman scattering signal and the necessary spectral resolution. Thus a spectral range of 1015 to 3695 cm ? 1 with spectral resolution of <13 cm ? 1 can be addressed.
PDF全文   HTML全文 Advanced Photonics, 2019年第1卷第5期 pp.055001-55001
Temporal contrast (TC) is one of the most important parameters of an ultrahigh intense laser pulse. The third-order autocorrelator or cross correlator has been widely used in the past decades to characterize the TC of an ultraintense laser pulse. A novel and simple single-shot fourth-order autocorrelator (FOAC) to characterize the TC with higher time resolution and better pulse contrast fidelity in comparison to third-order correlators is proposed. The single-shot fourth-order autocorrelation consists of a frequency-degenerate four-wave mixing process and a sum-frequency mixing process. The proof-of-principle experiments show that a dynamic range of ～1011 compared with the noise level, a time resolution of ～160 fs, and a time window of 65 ps can successfully be obtained using the single-shot FOAC, which is to-date the highest dynamic range with simultaneously high time resolution for single-shot TC measurement. Furthermore, the TC of a laser pulse from a petawatt laser system is successfully measured in single shot with a dynamic range of about 2 × 1010 and simultaneously a time resolution of 160 fs.
PDF全文   HTML全文 Advanced Photonics, 2019年第1卷第5期 pp.056001-56001
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In this issue of Advanced Photonics, Zoé-Lise Deck-Léger et al. offer an extremely insightful analysis of such spacetime crystals, where the dielectric function is modulated periodically in space and time. Exploring all four dimensions of our environment is certainly vertiginous and quite confusing at best. The authors overcome this challenge by focusing on 2D spacetime crystals with periodicity in time and in one space dimension. This way, they are able to use concepts from special relativity and provide explicit pictorial representations of the different optical phenomena associated with simultaneous spatial and temporal periodicities.
PDF全文 (下载：0) Advanced Photonics ，年第卷第期 pp.
Antonio-Lopez Jose E
Correa Rodrigo Amezcua
We demonstrate a deep-learning-based fiber imaging system that can transfer real-time artifact-free cell images through a meter-long Anderson localizing optical fiber for the first time. The cell samples are illuminated by an incoherent LED light source. A deep convolutional neural network is applied to the image reconstruction process. The network training uses data generated by a set-up with straight fiber at room temperature (~20 °C) but can be utilized directly for high fidelity reconstruction of cell images that are transported through fiber with a few degrees bend or fiber with segments heated up to 50 °C. In addition, cell images located several millimeters away from the bare fiber end can be transported and recovered successfully without the assistance of distal optics. We further evidence that the trained neural network is able to transfer its learning to recover images of cells featuring very different morphologies and classes that are never “seen” during the training process.
The Abbe’s diffraction limit that relates the maximum optical resolution to the numerical aperture of the lenses involved and the optical wavelength, is generally considered as “a practical frontier that cannot be overcome with a conventional imaging system.” However, it does not represent a fundamental limit to the optical resolution, as demonstrated with several new imaging techniques that proved the possibility of finding the subwavelength information from the far-field of an optical image, from super-resolution fluorescence microscopy to the imaging systems that use new data processing algorithms leading to a dramatically improved resolution to super-oscillating metamaterial lenses. This raises the key question of whether there’s in fact a fundamental bound to the optical resolution – as opposed to “practical” limitations due to noise and imperfections, and if so then what it is. In this work, we derive the fundamental limit to the resolution of optical imaging, and demonstrate that, while a bound to the resolution of a fundamental nature does exit, contrary to the conventional wisdom it is neither exactly equal to nor necessarily close to Abbe’s estimate. Furthermore, our approach to imaging resolution that combines the tools from the physics of wave phenomena and the methods of information theory.
The temporal contrast is one of the most important parameters of an ultra-high intense laser pulse. Third-order auto-correlator or cross-correlator have been widely used to characterize the temporal contrast of an ultra-intense laser pulse in the past decades. Here, a novel and simple single-shot fourth-order auto-correlator to characterize the temporal contrast with higher time resolution and better pulse contrast fidelity in comparison to third-order correlators is proposed. The single-shot fourth-order autocorrelation consists of a frequency degenerate four-wave mixing process and a sum-frequency mixing process. The proof-of-principle experiments show that a dynamic range of approximately 10^11 compared with the noise level, a time resolution of approximately 160 fs, and a time window of 65 ps can be successfully obtained using the novel single-shot fourth-order auto-correlator, which is the highest dynamic range with simultaneous high time resolution for single-shot temporal contrast measurement so far. Furthermore, the temporal contrast of a PW laser system is successfully measured in single-shot with a dynamic range of about 2×10^10 and a time resolution of 160 fs.
PDF全文 (下载：1) Advanced Photonics ，年第卷第期 pp.
We present a fully automated laser system with low intensity noise for coherent Raman scattering microscopy. The robust two-color system is pumped by a solid-state oscillator, which furthermore provides the Stokes pulses fixed at 1043 nm. The tunable 750 – 950 nm pump pulses are generated by a frequency-doubled fiber-feedback femtosecond optical parametric oscillator. The resulting pulse duration of 1.2 ps provides a viable compromise between optimal coherent Raman scattering signal and the necessary spectral resolution. Thus, a spectral range of 1015 – 3695 cm<sup>-1</sup> with spectral resolution of less than 13 cm<sup>-1</sup> can be addressed.
PDF全文 (下载：10) Advanced Photonics ，年第卷第期 pp.
Entanglement distribution between distant parties is one of the most important and challenging tasks in quantum communication. Distribution of photonic entangled states using optical fiber links is a fundamental building block towards quantum networks. Among the different degrees of freedom, orbital angular momentum (OAM) is one of the most promising due to its natural capability to encode high dimensional quantum states. In this article, we experimentally demonstrate fiber distribution of hybrid polarization-vector vortex entangled photon pairs. To this end, we exploit a recently developed air-core fiber which supports OAM modes. High fidelity distribution of the entangled states is demonstrated by performing quantum state tomography in the polarization-OAM Hilbert space after fiber propagation, and by violations of Bell inequalities and multipartite entanglement tests. The present results open new scenarios for quantum applications where correlated complex states can be transmitted by exploiting the vectorial nature of light.
PDF全文 (下载：2) Advanced Photonics ，年第卷第期 pp.
Diffractive deep neural networks have been introduced earlier as an optical machine learning framework that uses task-specific diffractive surfaces designed by deep learning to all-optically perform inference, achieving promising performance for object classification and imaging. Here we demonstrate systematic improvements in diffractive neural networks based on a differential measurement technique that mitigates the strict non-negativity constraint of light intensity. In this differential detection scheme, each class is assigned to a separate pair of detectors, behind a diffractive network, and the class inference is made by maximizing the normalized signal difference between the photodetector pairs. Using class-specific differential detection in jointly-optimized diffractive neural networks that operate in parallel, our simulations achieved blind testing accuracies of 98.52%, 91.48% and 50.82% for MNIST, Fashion-MNIST and grayscale CIFAR-10 datasets, respectively, coming close to the performance of some of the earlier generations of all-electronic deep neural networks. We also independently-optimized multiple diffractive networks and utilized them in a way that is similar to ensemble methods practiced in machine learning; using 3 independently-optimized differential diffractive neural networks that optically project their light onto a common output/detector plane, we numerically achieved blind testing accuracies of 98.59%, 91.06% and 51.44% for MNIST, Fashion-MNIST and grayscale CIFAR-10 datasets, respectively.
Synchronization is of importance in both fundamental and applied physics, but their demonstration at the micro/nanoscale is mainly limited to low-frequency oscillations like mechanical resonators. Here, we report the synchronization of two coupled optical microresonators, in which the high-frequency resonances in optical domain are aligned with reduced noise. It is found that two types of synchronization emerge with either the first- or second-order transition, both presenting a process of spontaneous symmetry breaking. In the second-order regime, the synchronization happens with an invariant topological character number and a larger detuning than that of the first-order case. Furthermore, an unconventional hysteresis behavior is revealed for a time-dependent coupling strength, breaking the static limitation and the temporal reciprocity. The synchronization of optical microresonators offers great potential in reconfigurable simulations of many-body physics and scalable photonic devices on a chip.
PDF全文 (下载：3) Advanced Photonics ，年第卷第期 pp.
We show that dielectric waveguides formed by materials with strong optical anisotropy support electromagnetic waves that combine the properties of propagating and evanescent fields. These "ghost waves" are created in tangent bifurcations that ``annihilate'' pairs of positive- and negative-index modes, and represent the optical analogue of the "ghost orbits" in the quantum theory of non-integrable dynamical systems. Ghost waves can be resonantly coupled to the incident evanescent field, which then grows exponentially through the anisotropic media -- as in the case of negative index materials. As ghost waves are supported by transparent dielectric media, the proposed approach to electromagnetic field enhancement is free from the ``curse'' of material loss that is inherent to conventional negative index composites.
Because of possessing a variety of fascinating and unexpected macroscopic phenomena, Bose-Einstein condensate (BEC) has attracted sustained attention in recent years---particularly for the field of solitons and associated nonlinear phenomena. Meanwhile, optical lattices have emerged as a versatile toolbox for understanding the properties and controlling the dynamics of BEC, among which an iconic result is the realization of bright gap solitons. However, the dark gap solitons are still unproven experimentally and their properties in more than one dimension remain unknown. We here survey, numerically and theoretically, the formation and stability properties of gap-type dark localized modes in the context of ultracold atoms trapped in optical lattices. Two kinds of stable dark localized modes---gap solitons and soliton clusters---are predicted in both the one- and two-dimensional geometries. The vortical counterparts of both modes are constructed as well in two dimension. A unique feature is the existence of nonlinear Bloch wave background on which all above gap modes are situated. Employing linear-stability analysis and direct simulations, stability regions of the predicted modes are obtained. Our results offer the possibility of observing dark gap localized structures with cutting-edge techniques in ultracold atoms experiments and beyond, including in optics with photonic crystals and lattices.