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Spatiotemporal dual-periodic soliton pulsation in a multimode fiber laser Opt. Lett. (IF 3.6) Pub Date : 2024-03-12 Wen-Yao He, Guang-Xin Liu, Jia-Wen Wu, Ye-Ting Qin, Zhi-Yin Feng, Guang-Xin Zhang, Wen-Jun Li, Hu Cui, Zhi-Chao Luo, Wen-Cheng Xu, and Ai-Ping Luo
Spatiotemporal mode-locked (STML) fiber lasers have become a new platform for investigating nonlinear phenomena. In this work, spatiotemporal dual-periodic soliton pulsation (SDSP) is firstly observed in an STML fiber laser. It is found that in the SDSP, the long-period pulsations (LPPs) of different transverse modes are synchronous, while the short-period pulsations (SPPs) exhibit asynchronous modulations
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Optimized pilot structure for PS-PDM ultrahigh-order QAM coherent optical transmission Opt. Lett. (IF 3.6) Pub Date : 2024-03-12 Xin Shi, Mingyi Gao, Xuejing Huang, Jiamin Fan, Xinbang Han, Xiaodi You, and Gangxiang Shen
We proposed and experimentally demonstrated a general pilot structure for probabilistic shaped (PS)-polarization division multiplexing (PDM) M-ary quadrature amplitude modulation (MQAM) coherent optical transmission, where a portion of PS-MQAM symbols is exploited as the pilot symbols with the same information entropy as the transmitted signal. The pilot symbols are simultaneously used in the entire
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Pre-equalization scheme for visible light communications with trial-and-error learning Opt. Lett. (IF 3.6) Pub Date : 2024-03-15 Shupeng Li, Yi Zou, Fangming Liu, and Jian Song
In this Letter, we propose a novel, to the best of our knowledge, neural network pre-equalizer based on the trial-and-error (TE) mechanism for visible light communication. This approach, unlike indirect learning (IL) architecture, does not require an additional auxiliary post-equalizer. Instead, it allows the pre-equalizer to be trained directly from the transmitter side through continuous interaction
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Coherent multi-band MIMO radar: robustness analysis to SSMF-based RF signal delivery Opt. Lett. (IF 3.6) Pub Date : 2024-03-11 Gaurav Pandey, Mirco Scaffardi, Salvatore Maresca, Malik Muhammad Haris Amir, Antonella Bogoni, and Antonio Malacarne
A numerical evaluation is conducted to assess the impact of distributing radio frequency (RF) signals through optical fiber links on the performance of a coherent multi-band multiple-input multiple-output (MIMO) radar system. The analysis focuses on scenarios where the antennas are widely separated in comparison to the employed signal wavelengths. The development of a model to quantify the phase noise
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High quality holographic 3D display with enhanced focus cues based on multiple directional light reconstruction Opt. Lett. (IF 3.6) Pub Date : 2024-03-11 Zi Wang, Li Liang, Tao Chen, Guoqiang Lv, Qibin Feng, Anting Wang, and Hai Ming
Holographic display faces the trade-off between image quality and focus cues, resulting from the specific choice of phase distribution. In this Letter, we propose a speckle-free holographic display with enhanced focus cues by multiple directional light reconstruction. The uniform phase hologram is first generated by the gradient descent optimization algorithm. The blazed grating phase is used to steer
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Performance evaluation of ground layer adaptive optics based on layer correction efficiency Opt. Lett. (IF 3.6) Pub Date : 2024-03-14 Ziming Li, Ying Yang, Lanqiang Zhang, Linhai Huang, and Changhui Rao
Ground layer adaptive optics (GLAO) has been widely employed in wide-field observations with ground-based telescopes. However, the present evaluation of GLAO performance lacks a criterion in terms of turbulence layer correction. This deficiency results in a significant gap in understanding the effectiveness of GLAO correction at different heights of the turbulence layer, thereby hindering the optimization
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Virtual reality images created on the back and front of a display Opt. Lett. (IF 3.6) Pub Date : 2024-03-15 Yoichi Ogata and Mykyta Kolchiba
To better investigate the biological mechanism of microorganisms, we developed a novel, to the best of our knowledge, virtual reality (VR) microscope that incorporates a head-mounted display (HMD) that creates VR images with a digital microscope. This type of VR microscope can be used with any type of optical microscope. The fabricated microscope is quite different from a common bifocal device because
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Demonstration of a 1 TW peak power, joule-level ultrashort Tm:YLF laser Opt. Lett. (IF 3.6) Pub Date : 2024-03-12 Issa Tamer, Zbynek Hubka, Leily Kiani, Jason Owens, Andrew Church, František Batysta, Thomas Galvin, Drew Willard, Andrew Yandow, Justin Galbraith, David Alessi, Colin Harthcock, Brad Hickman, Candis Jackson, James Nissen, Sean Tardiff, Hoang Nguyen, Emily Sistrunk, Thomas Spinka, and Brendan A. Reagan
We report on the demonstration of a diode-pumped, Tm:YLF-based, chirped pulse amplification laser system operating at λ ≈ 1.9 µm that produces amplified pulse energies exceeding 1.5 J using a single 8-pass power amplifier. The amplified pulses are subsequently compressed to sub-300 fs durations by a diffraction grating pair, producing record >1 TW peak power pulses. To the best of our knowledge, this
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GHz repetition rate, sub-100-fs Ho:CALGO laser at 2.1 µm with watt-level average power Opt. Lett. (IF 3.6) Pub Date : 2024-03-13 Weichao Yao, Mohsen Khalili, Yicheng Wang, Martin Hoffmann, Marcel van Delden, Thomas Musch, and Clara J. Saraceno
We report on a GHz fundamental repetition rate Kerr-lens mode-locked Ho:CALGO laser emitting at 2.1 µm. The laser employs a ring cavity to increase the fundamental repetition rate to 1.179 GHz and can be made to oscillate in both directions stably with nearly identical performance: for the counterclockwise oscillation, it generates 93-fs pulses at 1.68 W of average power, whereas 92 fs and 1.69 W were
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Multiple hyperbolic waves Opt. Lett. (IF 3.6) Pub Date : 2024-03-11 Zixun Ge, Shan Zhu, Wen Xiao, and Huanyang Chen
This study presents a conceptual design for a hyperbolic material utilizing transformation optics. This material is designed to produce multiple hyperbolic wave fields or polaritons excited by a point source. The design dictates key parameters including branch number, propagation range, and overall propagation direction of deflection. Through this approach, the hyperbolic material demonstrates new
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Beam-shaped femtosecond laser printing of quasi-capsule-shaped holographic terahertz metasurfaces Opt. Lett. (IF 3.6) Pub Date : 2024-03-11 Dan Rao, Jing Qian, Xiaohan Yu, Lequn Liu, Guande Wang, Yiwen Zhou, Teng Zhang, and Quanzhong Zhao
Terahertz (THz) metasurfaces have opened up a new avenue for the THz wavefront modulation. However, high-efficient and low-cost fabrication of THz metasurfaces remains a great challenge today. Here, quasi-capsule-shaped polarization-multiplexed holographic THz metasurfaces were printed by a beam-shaped femtosecond laser. The laser beam was spatially modulated by holograms of optimized cylindrical lens
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All-dielectric geometric metasurfaces for the generation and manipulation of perfect high-order Poincaré sphere beams Opt. Lett. (IF 3.6) Pub Date : 2024-03-13 Kaixiang Cheng, Yan Li, Zhendong Zhang, Yi Liu, Yanhua Han, and Xiaosai Wang
A high-order Poincaré sphere (HOPS) can be used to describe high-order modes of waveguides and vector beams, since it generalizes the feature of spin and the orbital angular momentum of light. HOPS beams are such beams with polarization states on the HOPS, which have potential applications in optical manipulation and optical communication. In general, the intensity distribution of this kind of beam
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Polarization-resolved super-resolution second-harmonic generation imaging based on multifocal structured illumination microscopy Opt. Lett. (IF 3.6) Pub Date : 2024-03-11 Yong Zhang, Chenshuang Zhang, Renlong Zhang, Rong Xu, Bin Yu, Danying Lin, and Junle Qu
Polarization-resolved second-harmonic generation (PSHG) microscopy is widely used in investigating the structural and morphological alterations of collagen. However, the resolution of second-harmonic generation (SHG) imaging remains constrained by optical diffraction, resulting in the polarization extraction of collagen characteristics from the average properties of collagen fibers. In this study,
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Super-resolution lensless on-chip microscopy based on array illumination and sub-pixel shift search Opt. Lett. (IF 3.6) Pub Date : 2024-03-14 Yulong Li, Jianshe Ma, Liangcai Cao, and Ping Su
The resolution of a lensless on-chip microscopy system is constrained by the pixel size of image sensors. This Letter introduces a super-resolution on-chip microscopy system based on a compact array light source illumination and sub-pixel shift search. The system utilizes a closely spaced array light source composed by four RGB LED modules, sequentially illuminating the sample. A sub-pixel shift search
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Quantifying distortion in time-correlated single photon counting: a universal parameter Opt. Lett. (IF 3.6) Pub Date : 2024-03-12 Angela Bovolenta, Alessandro Cominelli, Giulia Acconcia, and Ivan Rech
One major drawback of the classic time-correlated single photon counting (TCSPC) technique is pileup-related distortion. To keep it under a reasonable level, the maximum count rate has to be reduced, posing a serious limitation to the overall measurement speed. This means that there is an intrinsic trade-off between speed and distortion: either count rate is raised, but distortion is worsened, or distortion
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Multiwavelength erbium-doped fiber laser using the polarization-hole-burning effect for multichannel acoustic detection Opt. Lett. (IF 3.6) Pub Date : 2024-03-14 Cheng Zhou, Shengnan Zhou, Jiajun Tian, Yong Yao, and Yongkang Dong
We propose and demonstrate a novel, to the best of our knowledge, fiber-optic multipoint acoustic detection system based on a multiwavelength erbium-doped fiber (EDF) laser (MWEDFL) using the polarization-hole-burning effect with Fabry–Perot interferometers as the acoustic cavity-loss modulator. A polarization-wavelength-related filter is designed to assign a distinct polarization state to each laser
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Composite membrane of graphene oxide and gold nanoparticles functionalized S fiber taper aptasensor for highly sensitive bisphenol A detection Opt. Lett. (IF 3.6) Pub Date : 2024-03-14 Wanmei Guo, Yongsen Yu, Chao Xin, and Guangyong Jin
The S fiber taper (SFT) aptasensor with a composite sensitive membrane of graphene oxide and gold nanoparticles was proposed for the rapid and highly sensitive detection of bisphenol A (BPA). The SFT was obtained using a fusion splicer; subsequently, the composite film was deposited on its surface, and the specific aptamer was covalently bonded to the surface of gold nanoparticles. The detection mechanism
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Single-photon ranging lidar based on multi-repetition-rate pulse train correlation and accumulation Opt. Lett. (IF 3.6) Pub Date : 2024-03-15 Yan Kang, Xiaofang Wang, Tongyi Zhang, and Wei Zhao
A single-photon lidar based on multi-repetition-rate pulse train correlation and accumulation is proposed, and a ranging experiment is conducted on a 32 m target. By accumulating the correlation ranging results of pulse trains with internal spacings of 80, 100, and 125 ns, the signal-to-noise ratio of the cross correlation function is improved by about three-fold, which enables our method to improve
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Spectral causality-induced optical isolation in a non-Hermitian-modulated photonic cavity Opt. Lett. (IF 3.6) Pub Date : 2024-03-12 Awanish Pandey
An optical isolator is reported using a coupled cavity photonic molecule. It is shown that by non-Hermitian modulation of the coupling between the cavities, spectral causal and anti-causal response from the cavity can be obtained allowing the flexibility to regulate power between different Floquet modes. The distribution of optical energy between the Floquet modes is exploited to realize an optical
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Full Stokes polarimetry based on an inverse-designed multi-foci metalens Opt. Lett. (IF 3.6) Pub Date : 2024-03-13 Shuyi Wang, Tie Hu, Shichuan Wang, Yunxuan Wei, Zihan Mei, Bing Yan, Wenhong Zhou, Zhenyu Yang, JinKun Zheng, YuanLong Peng, and Ming Zhao
In the realm of metasurface-based polarimetry, well-known for its remarkable compactness and integration capabilities, previous attempts have been hindered by limitations such as the restricted choices of target polarization states and the inefficient focusing of light. To address these problems, this study introduces and harnesses a novel, to our knowledge, forward-solving model, grounded in the equivalence
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Selecting mode by the complex Berry phase in non-Hermitian waveguide lattices Opt. Lett. (IF 3.6) Pub Date : 2024-03-13 Lingzhi Zheng, Bing Wang, Chengzhi Qin, Lange Zhao, Shuyue Chen, Weiwei Liu, and Peixiang Lu
Bloch oscillations (BOs) in a parity-time (PT)-symmetric Su–Schrieffer–Heeger (SSH) waveguide array are theoretically investigated. We show that the BOs are amplified or damped even for the systems to exhibit entirely real energy bands. The amplified and damped BOs stem from the complex Berry phase and closely relate to the topological properties of the lattice. For the topological nontrivial lattice
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Optical structuring and finishing toward mid-spatial-frequency error reduction using femtosecond lasers Opt. Lett. (IF 3.6) Pub Date : 2024-03-11 Gong Chen and Jie Qiao
We demonstrate nano-structuring and the reduction of mid-spatial-frequency errors using femtosecond laser figuring and finishing. For the first time, to the best of our knowledge, we have corrected mid-spatial-frequency errors from 17 nm to one nanometer in magnitude. We established a method for creating and predicting periodic nanostructures. This demonstration opens the path of using femtosecond
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Interference-induced generation of a chirp-free short isolated attosecond pulse in the water window region with multicolor laser fields Opt. Lett. (IF 3.6) Pub Date : 2024-03-12 Jin-Xu Du, Guo-Li Wang, Xuan-Hong Gao, Xiao-Yong Li, Zhi-Hong Jiao, Song-Feng Zhao, and Xiao-Xin Zhou
Compensating for the intrinsic attosecond chirp (atto-chirp) of wideband high-order harmonics in the water window region is a significant challenge, in order to obtain isolated attosecond pulses (IAPs) with a width of tens of attoseconds (as). Here, we propose to realize the generation of IAP with duration as short as 20 as, central energy of 365 eV, and bandwidth exceeding 150 eV from chirp-free high
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Continuous tuning of pulse parameters in a soliton fiber laser by adjusting the effect of nonlinear polarization rotation: publisher’s note Opt. Lett. (IF 3.6) Pub Date : 2024-03-13 Xintong Zhang, Haozhe Guo, Wenbin He, Xiaocong Wang, Qi Huang, Yu Zheng, Ruochen Yin, Zhiyuan Huang, Xin Jiang, Lixin Xu, Yuxin Leng, and Meng Pang
This publisher’s note contains a correction to Opt. Lett. 49, 674 (2024) [CrossRef] .
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Mode conversion of various solitons in parabolic and cross-phase potential wells Opt. Lett. (IF 3.6) Pub Date : 2024-03-13 Qing Wang, Dumitru Mihalache, Milivoj R. Belić, and Ji Lin
We numerically establish the controllable conversion between Laguerre–Gaussian and Hermite–Gaussian solitons in nonlinear media featuring parabolic and cross-phase potential wells. The parabolic potential maintains the stability of Laguerre–Gaussian and Hermite–Gaussian beams, while the actual conversion between the two modes is facilitated by the cross-phase potential, which induces an additional
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Coverage extended MMF-based indoor OWC using overfilled launch and diversity reception Opt. Lett. (IF 3.6) Pub Date : 2024-03-12 Jin Shi, Yuzhe Wang, Xinda Yan, Zhengying Li, and Eduward Tangdiongga
Speckle patterns generated as coherent optical beams are reflected by scattering elements. Multimode fibers (MMFs) can modify the transverse intensity distribution of speckle patterns with macro perturbations, i.e., pressures, providing a simple and low-cost way to achieve equivalent beam-steering for indoor optical wireless communications (OWCs) with divergent optical beams. However, the received
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Wearable photoacoustic watch for humans Opt. Lett. (IF 3.6) Pub Date : 2024-03-11 Ting Zhang, Heng Guo, Weizhi Qi, and Lei Xi
Longitudinal detection of hemodynamic changes based on wearable devices is imperative for monitoring human healthcare. Photoacoustic effect is extremely sensitive to variations in hemoglobin. Therefore, wearable photoacoustic devices are apt to monitor human healthcare via the observation of hemodynamics. However, the bulky system and difficulties in miniaturizing and optimizing the imaging interface
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Tunability-selective lithium niobate light modulators via high-Q resonant metasurface Opt. Lett. (IF 3.6) Pub Date : 2024-03-11 Xiaoshan Liu, Guolan Fu, Shimei Song, Yikun Huang, Mulin Liu, Guiqiang Liu, and Zhengqi Liu
Herein, we propose and demonstrate an efficient light modulator by intercalating the nonlinear thin film into the optical resonator cavities, which introduce the ultra-sharp resonances and simultaneously lead to the spatially overlapped optical field between the nonlinear material and the resonators. Differential field intensity distributions in the geometrical perturbation-assisted optical resonator
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Coherent perfect absorption from asymmetry transmissive Helmholtz resonator metamaterials Opt. Lett. (IF 3.6) Pub Date : 2024-03-11 Wenbo Liu, Rui Yang, and Donghao Zhao
We propose an asymmetry transmissive (AT) Helmholtz resonator metamaterial to interact with dual incidences of different polarizations from opposite directions to achieve coherent perfect absorption at a terahertz regime. More specifically, the proposed design will solely allow the x-polarized incidence tunnel into the Helmholtz resonator cavity array with roughly half the energy reflected. Meanwhile
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Zeptojoule detection of terahertz pulses by parametric frequency upconversion Opt. Lett. (IF 3.6) Pub Date : 2024-03-11 Défi Junior Jubgang Fandio, Aswin Vishnuradhan, Eeswar Kumar Yalavarthi, Wei Cui, Nicolas Couture, Angela Gamouras, and Jean-Michel Ménard
We combine parametric frequency upconversion with the single-photon counting technology to achieve terahertz (THz) detection sensitivity down to the zeptojoule (zJ) pulse energy level. Our detection scheme employs a near-infrared ultrafast source, a GaP nonlinear crystal, optical filters, and a single-photon avalanche diode. This configuration is able to resolve 1.4 zJ (1.4 × 10–21 J) THz pulse energy
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Hyperspectral digital holography realized by using an electro-optical frequency comb via injection locking Opt. Lett. (IF 3.6) Pub Date : 2024-03-08 Ziwen Long, ZhengChao Yuan, Xinyu Fan, and Zuyuan He
Hyperspectral digital holography (HSDH) is a versatile holographic imaging technique that offers large unambiguous depth range and spectroscopic information. In this Letter, we propose a novel, to the best of our knowledge, HSDH system that is realized by using an electro-optical frequency comb (EOFC) via injection locking. In comparison with conventional dual-comb HSDH, the proposed system only requires
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Robust self-injection locking to a non-confocal monolithic Fabry–Perot cavity Opt. Lett. (IF 3.6) Pub Date : 2024-03-08 Anatoliy Savchenkov, Wei Zhang, Vladimir Iltchenko, and Andrey Matsko
We demonstrate an efficient simultaneous self-injection locking of two semiconductor lasers to high-order modes of a standalone monolithic non-confocal Fabry–Perot cavity. The lasers are used to generate a low-noise microwave signal on a fast photodiode. The overall improvement of the laser spectral purity exceeds 80 dB. The observed single-sideband phase noise of X- to W-band signals is at the −110
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Wavelength conversion through stimulated Raman scattering in an oxygen-filled fiber for multi-band LiDAR Opt. Lett. (IF 3.6) Pub Date : 2024-03-07 Micah Raab, Daniel Leaird, Trevor L. Courtney, Christian Keyser, and Rodrigo Amezcua Correa
Wavelength conversion afforded by stimulated Raman scattering within a hollow core fiber is potentially useful for multispectral light detection and ranging (LiDAR). Herein, we make use of the ideal 1550 cm−1 vibrational Raman shift of an antiresonant fiber filled with gaseous oxygen so that the first and second Raman orders as well as the transmitted pump are all located in separate atmospheric transmission
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Selective excitation of high-order modes in two-dimensional cavity resonator integrated grating filters Opt. Lett. (IF 3.6) Pub Date : 2024-03-07 Antoine Rouxel, Olivier Gauthier-Lafaye, Antoine Monmayrant, and Stéphane Calvez
The selective spatial mode excitation of a bi-dimensional grating-coupled micro-cavity called a cavity resonator integrated grating filter (CRIGF) is reported using an incident beam shaped to reproduce the theoretical emission profiles of the device in one and subsequently two dimensions. In both cases, the selective excitation of modes up to order 10 (per direction) is confirmed by responses exhibiting
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Large-range two-dimensional sub-nano-misalignment sensing for lithography with a piecewise frequency regression network Opt. Lett. (IF 3.6) Pub Date : 2024-03-07 Nan Wang, Yi Li, Wei Jiang, Zhen’an Qin, and Jun Liu
Circular gratings have been traditionally used as coarse alignment markers rather than fine ones for carrying out two-dimensional (2D) large-range misalignment measurements. This is primarily due to its complex phase distribution, which renders the extraction of information from high-precision alignment challenging using conventional frequency filtering methods. Along these lines, in this work, a novel
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Formation of electromagnetic pulses with nonzero electrical area by media with ferromagnetism Opt. Lett. (IF 3.6) Pub Date : 2024-03-07 Nikolay N. Rosanov
The known rule of conservation of the electrical area of pulses, which plays a decisive role in the effectiveness of the action of extremely short pulses on microobjects, is valid for a wide class of media, including all non-magnetic ones. We show how this rule changes in magnetically ordered media, where pulses can induce magnetization variation. We found that such variations serve as another source
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Adaptive layer-based computer-generated holograms Opt. Lett. (IF 3.6) Pub Date : 2024-03-07 Yongwei Yao, Yaping Zhang, Qingyang Fu, Jilu Duan, Bing Zhang, Liangcai Cao, and Ting-chung Poon
We propose a novel, to the best of our knowledge, and fast adaptive layer-based (ALB) method for generating a computer-generated hologram (CGH) with accurate depth information. A complex three-dimensional (3D) object is adaptively divided into layers along the depth direction according to its own non-uniformly distributed depth coordinates, which reduces the depth error caused by the conventional layer-based
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Ultra-broadband frequency shifting of laser pulses in a square multicore chalcogenide fiber Opt. Lett. (IF 3.6) Pub Date : 2024-03-07 Alexey Balakin, Sergey Skobelev, Alexey Andrianov, Elena Anashkina, and A. G. Litvak
The process of Raman frequency shifting of out-of-phase laser pulses in fibers with a square configuration of weakly coupled cores having two or more zero dispersion wavelengths has been studied. The use of out-of-phase distributions in multicore fibers makes it possible to increase pulse energies by orders of magnitude in comparison with the case of single-core fibers. Conditions for the stability
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Coherent states of the Laguerre–Gauss modes Opt. Lett. (IF 3.6) Pub Date : 2024-03-07 M. P. Morales Rodríguez, O. S. Magaña-Loaiza, B. Perez-Garcia, L. M. Nieto Calzada, F. Marroquín Gutiérrrez, and B. M. Rodríguez-Lara
Large quantum photonic systems hold promise for surpassing classical computational limits, yet their state preparation remains a challenge. We propose an alternative approach to study multiparticle dynamics by mapping the excitation mode of these systems to physical properties of the Laguerre–Gauss modes. We construct coherent states establishing a direct link between excitation number dynamics and
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Designing high thermally stable deep red phosphors based on low thermal expansion coefficients for optical applications Opt. Lett. (IF 3.6) Pub Date : 2024-03-07 Jianqiang Sun, Mochen Jia, Wei Xu, Mingli Wang, and Zhen Sun
Mn4+-activated oxide phosphors with low cost and unique luminescent properties have been considered as a promising candidate for various optical applications, while the search for high thermal stable red-emitting phosphors is still a huge challenge. In our work, we find and unveil the relationship between luminescence thermal quenching behavior and thermal expansion coefficients (α/10−6 K−1) based
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Multispectral stealth multilayer etched film structure based on ultrathin silver Opt. Lett. (IF 3.6) Pub Date : 2024-03-07 Heyan Wang, Yingzheng Ren, Wenjing Geng, Lin Han, Yilei Zhang, Danni Zheng, Zhengang Lu, and Jiubin Tan
Spontaneous infrared radiation dissipation is a critical factor in facilitating object cooling, which influences the thermal stability and stealth efficacy of infrared stealth devices. Furthermore, the compatibility between efficient visible, infrared, and radar stealth is challenging due to different camouflage principles in different bands. This Letter presents a five-layer etched film structure
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Improvement of light extraction efficiency in AlGaInP-based vertical miniaturized-light-emitting diodes via surface texturing Opt. Lett. (IF 3.6) Pub Date : 2024-03-04 Siyuan Cui, Lang Shi, Leonard Jin, Qianxi Zhou, Yuechang Sun, Conglong Jin, Jiahui Hu, Kuosheng Wen, Zhou Xu, and Shengjun Zhou
AlGaInP-based light-emitting diodes (LEDs) suffer from a low external quantum efficiency (EQE), which is mainly restrained by the poor light extraction efficiency. Here, we demonstrate AlGaInP-based vertical miniaturized-LEDs (mini-LEDs) with a porous n-AlGaInP surface using a wet etching process to boost light extraction. We investigated the effects of etching time on the surface morphology of the
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Loss-free shaping of few-cycle terawatt laser pulses Opt. Lett. (IF 3.6) Pub Date : 2024-03-04 L. M. Railing, M. S. Le, C. M. Lazzarini, and H. M. Milchberg
We demonstrate loss-free generation of 3 mJ, 1 kHz, few-cycle (5 fs at 750 nm central wavelength) double pulses with a pulse peak separation from 10 to 100 fs, using a helium-filled hollow core fiber (HCF) and chirped mirror compressor. Crucial to our scheme are simulation-based modifications to the spectral phase and amplitude of the oscillator seed pulse to eliminate the deleterious effects of self-focusing
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Hybrid spherical array for combined volumetric optoacoustic and B-mode ultrasound imaging Opt. Lett. (IF 3.6) Pub Date : 2024-03-06 Hsiao-Chun Amy Lin, Xosé Luís Deán-Ben, Ali Ozbek, Yi-Hsuan Shao, Berkan Lafci, and Daniel Razansky
Optoacoustic (OA) imaging has achieved tremendous progress with state-of-the-art systems providing excellent functional and molecular contrast, centimeter scale penetration into living tissues, and ultrafast imaging performance, making it highly suitable for handheld imaging in the clinics. OA can greatly benefit from efficient integration with ultrasound (US) imaging, which remains the routine method
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High-efficiency narrow-bandwidth KTP optical parametric oscillator for kHz–MHz planar laser-induced fluorescence Opt. Lett. (IF 3.6) Pub Date : 2024-03-06 Austin M. Webb, Christopher Q. Crabtree, Venkat Athmanathan, Terrence R. Meyer, Sean P. Kearney, and Mikhail N. Slipchenko
The electronic excitation of key combustion species or flow tagging of chemical species requires a narrowband tunable UV source. In this work, a potassium titanyl phosphate (KTP) burst-mode optical parametric oscillator (OPO) pumped by a 532 nm laser is developed to generate a spectrally narrow signal and an idler output with 1.48 ± 0.19 cm−1 bandwidth without the need for injection seeding. The idler
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Visible-NIR surface plasmon resonance sensing technology for high precision refractive index detection Opt. Lett. (IF 3.6) Pub Date : 2024-03-06 Zhiyong Yin and Xili Jing
Molybdenum disulfide (MoS2), as a representative transition metal disulfide material, has contributed significantly to the development of plasmonic technology toward the near-infrared (NIR). In this Letter, the physical mechanism of MoS2 excitation of surface plasmon resonance (SPR) in the NIR is investigated, and it is shown that the MoS2 film can induce the resonance dip to move toward the NIR and
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Guided wave resonance-based digital holographic microscopy for high-sensitivity monitoring of the refractive index Opt. Lett. (IF 3.6) Pub Date : 2024-03-05 Chunyu Wang, Jingyu Mi, Hua Lu, Shouhao Shi, Jianxu Zhao, Dikun Li, Jiwei Zhang, Jiadeng Zheng, and Jianlin Zhao
Surface plasmon resonance holographic microscopy (SPRHM) has been employed to measure the refractive index but whose performance is generally limited by the metallic intrinsic loss. Herein we first, to our knowledge, utilize guided wave resonance (GWR) with low loss to realize the monitoring of the refractive index by integrating with digital holographic microscopy (DHM). By depositing a dielectric
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Bifurcation of bound states in the continuum in periodic structures Opt. Lett. (IF 3.6) Pub Date : 2024-03-05 Nan Zhang and Ya Yan Lu
In lossless dielectric structures with a single periodic direction, a bound state in the continuum (BIC) is a special resonant mode with an infinite quality factor (Q factor). The Q factor of a resonant mode near a typical BIC satisfies Q∼1/(β−β∗)2 , where β and β∗ are the Bloch wavenumbers of the resonant mode and the BIC, respectively. However, for some special BICs with β∗=0 (referred to as super-BICs
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Loading-effect-based three-dimensional microfabrication empowers on-chip Brillouin optomechanics Opt. Lett. (IF 3.6) Pub Date : 2024-03-05 Peng Lei, Mingyu Xu, Yunhui Bai, Zhangyuan Chen, and Xiaopeng Xie
The acousto-optic interaction known as stimulated Brillouin scattering (SBS) has emerged as a fundamental principle for realizing crucial components and functionalities in integrated photonics. However, the main challenge of integrating Brillouin devices is how to effectively confine both optical and acoustic waves. Apart from that, the manufacturing processes for these devices need to be compatible
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Increasing contrast in water-embedded particles via time-gated mid-infrared photothermal microscopy Opt. Lett. (IF 3.6) Pub Date : 2024-03-05 Panagis D. Samolis and Michelle Y. Sander
The transient dynamics of photothermal signals provide interesting insights into material properties and heat diffusion. In a mid-infrared (mid-IR) photothermal microscope, the imaging contrast in a standard amplitude imaging can decrease due to thermal diffusion effects. It is shown that contrast varies for poly-methyl 2-methylpropenoate (PMMA) particles of different sizes when embedded in an absorbing
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Aplanatic solar concentrators for tubular absorbers Opt. Lett. (IF 3.6) Pub Date : 2024-03-04 Leonardo F. L. de Souza, Naum Fraidenraich, and Jeffrey M. Gordon
A fundamentally new, to the best of our knowledge, class of linear (2D) dual-mirror aplanats tailored to tubular absorbers is developed for the types of solar concentrators used for thermal power. It is shown that prior investigation establishing this concept possesses unrecognized additional designs, as well as having missed high-performance configurations. It is shown that our line-focus solar concentrators
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Experimental comparison of E-band BDFA and Raman amplifier performance over 50 km G.652.D fiber using 30 GBaud DP-16-QAM and DP-64-QAM signals Opt. Lett. (IF 3.6) Pub Date : 2024-03-04 Aleksandr Donodin, Pratim Hazarika, Mingming Tan, Dini Pratiwi, Shabnam Noor, Ian Phillips, Paul Harper, and Wladek Forysiak
We compare the performance of three optical amplifiers in the E-band: a bismuth-doped fiber amplifier (BDFA), a distributed Raman amplifier, and a discrete Raman amplifier (RA). Data transmission performance of 30 GBaud DP-16-QAM and DP-64-QAM signals transmitted over 50 km of G.652.D fiber is compared in terms of achieved signal-to-noise (SNR). In this specific case of relatively short distance, single-span
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High-performance multi-junction cascade 1.3 µm quantum dot vertical cavity surface-emitting laser Opt. Lett. (IF 3.6) Pub Date : 2024-03-04 Song Ping, Xue Yu Bo, Dong Hai Liang, Jia Zhi Gang, Jia Wei, Liang Jian, Wang Zhi Yong, and Xu Bing She
A high-performance 5-junction cascade quantum dot (QD) vertical cavity surface-emitting laser (VCSEL) with 1.3 µm wavelength was designed. The characteristics of the QD as active regions and tunnel junctions are combined to effectively increase output power. The photoelectric characteristics of single-junction, 3-junction cascade, and 5-junction cascade QD VCSELs are compared at continuous-wave conditions
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Optical path optimization of chromatic line confocal displacement sensor for high resolution and wide range Opt. Lett. (IF 3.6) Pub Date : 2024-03-04 Shuai Wang, Kuan Diao, Xiaojun Liu, and Chuqiao Gong
This study introduces the optical path-optimized dual-grating chromatic line confocal imaging (DG-LCI) technique for high-resolution and wide-range surface topography measurements. Chromatic line confocal imaging (LCI) finds extensive applications in high-speed 3D imaging of surface morphology, roughness analysis in industrial production, and quality inspection. A key advantage of LCI is its ability
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Tunable double notch filter on a thin-film lithium niobate platform Opt. Lett. (IF 3.6) Pub Date : 2024-03-04 Songyan Hou, Hao Hu, Zhihong Liu, Weichuan Xing, Jincheng Zhang, and Yue Hao
Tunable optical filters at the chip scale play a crucial role in fulfilling the need for reconfigurability in channel routing, optical switching, and wavelength division multiplexing systems. In this Letter, we propose a tunable double notch filter on thin-film lithium niobate using dual microring architecture. This unique integrated filter is essential for complex photonic integrated circuits, along
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Ultrathin metasurface on a 100 nm-thick dielectric membrane absorbs infrared rays Opt. Lett. (IF 3.6) Pub Date : 2024-03-04 Harumi Asada and Takehito Suzuki
Flat optics based on metasurfaces produce unprecedented two-dimensional planar optical elements that cannot be developed with naturally occurring materials. However, it remains to be shown whether metasurfaces on ultrathin dielectric membranes can be adopted in a broad range of optical elements as flat optics. Here we demonstrate that a fabricated ultrathin metasurface composed of double-sided metal
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Gradient-metasurface directional photodetectors Opt. Lett. (IF 3.6) Pub Date : 2024-03-04 Jianing Liu and Roberto Paiella
Angle-sensitive photodetectors are a promising device technology for many advanced imaging functionalities, including lensless compound-eye vision, lightfield sensing, optical spatial filtering, and phase imaging. Here we demonstrate the use of plasmonic gradient metasurfaces to tailor the angular response of generic planar photodetectors. The resulting devices rely on the phase-matched coupling of
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Magnetic-field-assisted optical fiber quantum temperature sensor with enhanced sensitivity Opt. Lett. (IF 3.6) Pub Date : 2024-03-04 Jiayao Chen, Yunhan Luo, Jiajia Luo, Huanhuan Huang, Hongda Cheng, Gui-shi Liu, Lei Chen, Zhe Chen, and Yaofei Chen
In recent years, utilizing nitrogen-vacancy color centers in diamond for temperature sensing has drawn great attention. However, increasing the sensitivity has encountered challenges due to the intrinsic temperature-dependent energy level shift, i.e., temperature responsivity, being limited to -74 kHz/K. In this Letter, we take advantage of the magnetic field to regulate the energy level to enhance
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Optimal parameter selection for the THz-CCS system based on an incoherent light source Opt. Lett. (IF 3.6) Pub Date : 2024-03-04 Cong Cheng, Fan Huang, Zuolong Li, Donglin Sun, Xunyuan Jin, Jianqiang Gu, Jiaguang Han, and Weili Zhang
Terahertz cross correlation spectroscopy (THz-CCS) systems using broadband incoherent light as the pumping source have received increasing attention from researchers in recent years. However, a comprehensive and in-depth understanding of THz-CCS is still needed to obtain a detailed optimization scheme. Here we systematically investigate the influences of the detection parameters, light propagation
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Configurable SNAP microresonators induced by axial pre-strain-assisted CO2 laser exposure Opt. Lett. (IF 3.6) Pub Date : 2024-02-29 Qi Yu, Zhenxiang Xu, Zuowei Xu, Yulong Wang, Haosen Li, Qi Miao, Hongtao Li, Xuewen Shu, and Liang Lu
Flexible engineering of the complex shapes of the surface nanoscale axial photonics (SNAP) bottle microresonators (SBMs) is challenging for future nanophotonic technology applications. Here, we experimentally propose a powerful approach for the one-step fabrication of SBMs with simultaneous negative and positive radius variations, exhibiting a distinctive “bump-well-bump” profile. It is executed by