bluuebunny/crossref_metadata_2025 huggingface dataset:
Brillouin Fiber Sensor Based on Optical Frequency Comb and Heterodyne Detection
Authors: Ono Takuma , Tanaka Yosuke , Shioda Tatsutoshi
Published: July 2023

We have proposed a new detection method of Brillouin frequency shift measurement technique using optical comb and heterodyne detection technology. In this paper, the experimental results are shown for the confirmation of the operation principle.
Continuous Synthesis of Arbitrary Optical Waveforms on a Sub-Femtosecond Timescale
Authors: Tomura Akihiro , Ohae Chiaki , Nakagawa Ken-ichi , Minoshima Kaoru , Katsuragawa Masayuki
Published: July 2023

We report a technology for synthesizing electric fields of light of arbitrary waveforms on a sub-femtosecond timescale. Five discrete harmonics are arbitrarily manipulated to generate a train of ultrashort waveforms with 890-attosecond temporal duration.
High-Quality Compression of Ultrafast UV Light in Gas-Filled Hollow-Core Photonic Crystal Fibers
Authors: Novoa David , Luan Jie , Russell Philip St.J.
Published: July 2023

Nonlinear self-compression in gas-filled hollow-core fibers generates ~8.5 fs UV pulses with ~98% of the pulse energy within a single temporal lobe. The approach may find applications in time-resolved spectroscopy and chemistry.
High-energy, sub-8 fs green pulse generation
Authors: Tsai Chia-Lun , Liang An-Yuan , Xie Liang-Xian , Liu Shih-Cheng , Lai Po-Wei , Tsai Ming-Shiang , Lin Ming-Wei , Chen Ming-Chang
Published: July 2023

We propose a new method of pulse post-compression, named CAScaded foCusing AnD comprEssing (CASCADE) to nonlinearly compress 0.6-mJ, 515-nm pulses from 148 fs to 7.8 fs with an output energy of 0.28 mJ.
Influence of Resonant Bands on UV Generation in Gas- filled Antiresonant Hollow-core Fiber
Authors: Xiong Daiqi , Wang Yuxi , Chang Wonkeun
Published: July 2023

We investigate the influence of resonant bands in ultraviolet generation in gas- filled antiresonant hollow-core fibers. Their presence in the vicinity of the phase-matching point substantially degrades the efficiency and quality of the frequency up-conversion process.
Soft Time Stretch: Boosting the Stretch Factor by Deep Learning
Authors: Zhou Yiming , Zhou Tingyi , Jalali Bahram
Published: July 2023

We propose the concept of Soft Time Stretch, a technique that boosts the stretch factor of classic time-stretch systems by exploiting deep learning and nonlinear optics.
Lasing performance of Yb:YAG thin-disk with crystalline coatings directly bonded onto silicon carbide heatsink
Authors: Cimrman Martin , Cvrček Jan , Vojna David , Štěpánková Denisa , Foršt Ondřej , Smrž Martin , Novák Ondřej , Slezák Ondřej , Chyla Michal , Jelínek Michal , Mužík Jiří , Mocek Tomáš
Published: July 2023

The lasing properties of a crystalline-coated Yb:YAG thin disk bonded onto a SiC heatsink in a multi-mode cavity are investigated, including disk temperature, output power, and dioptric power. The coatings show improvement over conventional ones.
Picosecond CPA Fiber Laser with 0.4 mJ Pulse Energy and 423 W Average Power Based on XLMA Triple-clad Fiber
Authors: Wang Beibei , Peng Zhigang , Xu Yan , Cheng Zhaochen , Wang Pu
Published: July 2023

A high-average-power 0.4-mJ picosecond chirped pulse amplification (CPA) system based on an Extra-Large-Mode Area (XLMA) 100/400/480 µm Yb-doped Triple Clad Fiber (TCF) is demonstrated. The pulse energy of 0.62 mJ with an average power of 620 W is obtained in the main TCF amplifier. After pulse compression, an average power of 423 W with a pulse duration of 7.6 ps is achieved indicating a high peak power of 55.7 MW. To the best of our knowledge, this is the highest output ultrashort pulse energy at 400-W scale by using an Yb-doped TCF.
Parametric Amplification of Passively Phase Locked Intense Mid-Infrared Pulses with 100 kHz repetition
Authors: Kurihara Takayuki , Yang Tianqi , Mizuno Tomoya , Kanai Teruto , Itatani Jiro
Published: July 2023

Few-cycle femtosecond optical parametric amplifier in the 1.8-2.5 µm region is developed based on Yb;KGW source, exhibiting passively stabilized carrier-envelope phase, pulse energy of tens of µJ and tunable repetition rates up to 100 kHz.
Bandwidth Evaluation of Orthogonal Lattice Waveguide (OLW) for Circular Defect in Photonic Crystal (CirD) Lasers
Authors: Morita Masaya , Hirata Shotaro , Higuchi Takuya , Kaichi Kenta , Zuo Rubing , Ye Hanqiao , Kajii Hirotake , Morifuji Masato , Maruta Akihiro , Kondow Masahiro
Published: July 2023

We fabricate CirD lasers with Orthogonal Lattice Waveguides and evaluate them by optical pumping. We have experimentally confirmed that the wavelength range of OLW is 20 nm, which is about double for the conventional W1 waveguide.
Advanced Dry Etching of GaAs/AlGaAs Multilayer Wafer for Circular Defect in Photonic Crystal (CirD) Laser
Authors: Ye Hanqiao , Xiong Yifan , Zuo Rubing , Morita Masaya , Kaichi Kenta , Maruta Akihiro , Kajii Hirotake , Morifuji Masato , Kondow Masahiko
Published: July 2023

We improved dry etching process by introducing 3-steps etching and 3 layers of quantum dots for fabricating the CirD laser that will be used for intra-chip optical communications. Excellent lasing property was consequently obtained.
Measurement of Scattered Fluorescence Light by TIE-based 3D Fluorescence Imaging Technique
Authors: Shoda Marin , Quan Xiangyu , Murata Takashi , Awatsuji Yasuhiro , Matoba Osamu
Published: July 2023

Complex amplitude distribution of scattered fluorescence light is measured by TIE-based 3D fluorescence imaging technique. We present a preliminary experiment in tobacco cultured cells expressing GFP with tubulin covered by a diffused medium.
Multi-photon activation of fluorescent proteins using visible wavelength for high-resolution imaging
Authors: Kubo Toshiki , Temma Kenta , Sugiura Kazunori , Shinoda Hajime , Lu Kai , Smith Nicholas I. , Matsuda Tomoki , Nagai Takeharu , Fujita Katsumasa
Published: July 2023

We experimentally demonstrated the photo-activation of reversibly photo-switchable fluorescent proteins by visible-wavelength two-photon excitation and applied the activation technique in confocal imaging of biological cells. Higher spatial resolution than conventional confocal microscopy was confirmed.
Surface scattering in periodic metamaterials
Authors: Zhang Tieyan , Yu Jiachen , Wulan Qiqige , Li Zhe , Liu Zhijun
Published: July 2023

Surface light scattering in periodic metamaterials is characterized. Diffuse reflection is shown to occur at wavelengths less than that of the first order Rayleigh anomaly as dominated by grating diffractions from structural periodicity.
Performance Estimation of EO-Polymer Plasmonic Optical Phased Array
Authors: Kuwamura Yuji , Hibata Kyosuke
Published: July 2023

We proposed a new type of plasmonic optical phased array consisting of an array of plasmonic phase modulators based on electro-optic polymers[1]. The proposed device has only one optical peak at a wavelength of 1.55um, and the output light can be deflected and scanned over a range of more than 100 degrees by voltage control, which is confirmed by numerical calculation using the two-dimensional FDTD method. A Small-sized (70*26um2), low-voltage (Less than 10V), high-speed and low-power optical phased array could be designed.
Metal-Insulator-Metal Structured Surface Plasmon Polariton Waveguide with Improved Gain
Authors: Chaparala Rishiteja , Tupakula Sreenivasulu
Published: July 2023

Design and analysis of spoof surface plasmon polariton waveguide is presented in this work. The novel structure exhibits an improved gain of 6.973dBi with an increment of 0.83dBi compared to the existing designs.
Multiple Anapole States in Free-standing Silicon Nanodisk
Authors: Pradhan Monica , Sharma Shubhanshi , Bhaktha S.K. , Varshney Shailendra K
Published: July 2023

Through finite-element 3D simulations, we achieve the multiple anapole states, in a single silicon nanodisk at 522 nm (pseudo-anapole) and 815 nm (higher-order anapole) wavelengths which can be used for multitude applications.
A Compact Detector Module for Remote Characterization of Ultrashort Pulses Delivered over Dynamic Fiber-optic Links
Authors: C G Lakshmi , Supradeepa V R
Published: July 2023

We demonstrate remote characterization and dispersion compensation of ultrashort pulses delivered over dynamic fiber-optic links using a nonlinear crystal, power detectors, and a pulse shaper-based interferometer. Measurements of sub-400fs pulses agree well with conventional measurements.
Novel approach for distinguishing 2H/1T-1T' molybdenum disulfide(MoS2) optical nonlinearity
Authors: Su Shih-Po , Huang Yi-Hsuan , Lan Jia-Qi , Tu Li-Wei , Wadekar Paritosh V. , Wang Hsiang-Chen , Lee Chao-Kuei
Published: July 2023

2H/1T-1T' molybdenum disulfide(MoS2) are typical phase existed during the crystal or thin materials preparation. In this work, by controlling the atmosphere during the CVD thin film preparation, 2H/1T-1T' MoS2 are separately growth. Additionally, by z-scan technique, the phase dependent optical nonlinearity of MoS2 was observed and investigated.
Quasi-phase-matching properties of MgO:PPSLT in the oo-e, oo-o, and oe-o interactions
Authors: Umemura Nobuhiro , Hirohashi Junji
Published: July 2023

We measured the quasi-phase-matching temperatures for SHG at 0.5321 µm with the oo-e, oo-o, and oe-o interactions in periodically poled 1mol% MgO doped stoichiometric lithium tantalate (MgO:PPSLT). The cross points of the temperature tuning curves of the QPM processes with different interactions exist around 80°C in this QPM device.
Phase noise of THz wave generated by a combination of microresonator soliton comb with uni-traveling-carrier photodiode
Authors: Okada S. , Nishimato K. , Tokizane Y. , Kuse N. , Yasui T.
Published: July 2023

Optical-to-THz conversion of microcomb with uni-traveling-carrier photodiode is a potential method to generate CW-THz wave with ultra-high frequency, low phase noise, and high practicability. In this paper, we evaluated the phase noise of CW-THz wave at 560 GHz.
Characterization of UV-responsive Properties of DNA:PEDOT Biomaterial by Time-Domain Terahertz Spectroscopy
Authors: Huang Chia-Hsin , Chuang Wei-Tsung , Hung Yu-Chueh
Published: July 2023

We present refractive indices, conductivities, and carrier-related parameters of newly developed DNA:PEDOT biomaterial using time-domain terahertz spectroscopy. Our results reveal UV-responsive electrical properties of the complex, which may be further utilized for biomaterial-based optoelectronic devices.
Traffic Prediction Model for Optical Network Based on Multi-input Neural Network
Authors: Liu Yan , Hu Qian , Huo Xiaoli , Zhang Anxu
Published: July 2023

A novel traffic prediction model for optical network is proposed based on Multi-input Neural Network. Results indicate that the proposed model shows better performances than other prediction models in this experiment.
Classifying Nitrate in Aqueous Solution using Supervised Machine Learning based on Spectroscopic Technique
Authors: Sulaiman Rozita , Azeman Nur Hidayah , Nazri Nur Afifah Ahmad , Bakar Mohd Hafiz Abu , Masran Athiyah Sakinah , Bakar Ahmad Ashrif A
Published: July 2023

We demonstrate the classification of nitrate concentration in mixed solution based on spectroscopy measurements. Dimensionality reduction techniques and supervised machine learning classifiers were employed where the PCA-SVM model outperforms other models with 97.8% accuracy.
Development of compact, high-energy Yb:YAG passive Q-switch laser for pumping intense infrared lasers
Authors: Akahane Yutaka , Yamakawa Koichi
Published: July 2023

Compact, intense passive Q-switch lasers with Yb:YAG/Cr:YAG composite ceramics have been generated 3-mJ, 3-ns laser pulses at 60-Hz for pumping infrared lasers, which is increased to 6.3-mJ and 12.0-ns with cavity extension.
Dynamic Characteristics of Quantum Cascade Lasers near Threshold Oscillation with Optical Feedback
Authors: Harimoto Tetsuo , Iguchi Daiki
Published: July 2023

The dynamic characteristics of quantum cascade lasers with optical feedback are numerically analyzed with a conventional rate-equation model. Simulation results showed that chaotic phenomena also occur in the quantum cascade laser near the threshold oscillation with optical feedback.
High-Speed Imaging of Ice Crystallization Dynamics Triggered by Laser Ablation
Authors: Takahashi Hozumi , Tsuri Yuka , Maruyama Mihoko , Yoshimura Masashi , Nakabayashi Seiichiro , Mori Yusuke , Yoshikawa Hiroshi Y.
Published: July 2023

Crystallization control by laser ablation of liquid is promising for enforcing crystal nucleation in a spatio-temporal manner. In this work, we have demonstrated ice crystallization by laser ablation of water with a single laser pulse, which allowed for the detailed study of ice crystallization with high-speed imaging. The systematic results clearly showed the ice crystallization with bubbles that were formed by laser ablation of water.
Surface cleavage of zinc oxide induced by femtosecond laser irradiation
Authors: Yu Xi , Takeda Yuma , Hamasaki Shuta , Ishida Takafumi , Kuwahara Makoto , Saitoh Koh , Itoigawa Fumihiro , Ono Shingo
Published: July 2023

Cleavage along the crystalline and cleavage-melt shift were observed on the surface of a ZnO substrate when it was irradiated by single and multiple femtosecond laser pulses, respectively.
Active light shift suppression in CPT atomic clock
Authors: Andryushkov V. , Radnatarov D. , Kobtsev S. , Basalaev M. , Yudin V.
Published: July 2023

We demonstrated experimental implementation of coherent population trapping resonance phase-jump spectroscopy consisting of discrete phase modulation of the bichromatic pumping radiation frequency difference which allows error signal generation for the resonance active light shift elimination.
Linewidth Simulation of Littman/Metcalf External Cavity Diode Laser using Curvature Controlled End Mirror
Authors: Kato Naoaki , Takiguchi Yu
Published: July 2023

A dynamic and broad linewidth modulation method with an external cavity diode laser is introduced. The transmission line laser model simulation revealed the tuning range of linewidth from 250 kHz to 50 GHz.
RF signal estimation utilizing low-frequency beat signal due to harmonics of phase-modulation lightwave
Authors: Chiba Akito , Sunaga Yusuke
Published: July 2023

We propose a method for estimating parameters of an RF-signal within high-frequency region, by adopting a low-frequency reference RF signal source to generate harmonics of the modulation lightwave.
A robust frequency stabilized of Er:fiber frequency comb with relative frequency instability of E-18
Authors: Yan Lulu , Li Mingkun , Yang Xiguang , Zhang Yanyan , Zhang Pan , Rao Bingjie , Chen Xin , Yuan Ru , Guo Wenge , Zhang Shougang , Jiang Haifeng
Published: July 2023

Highly stable and long-term frequency-controlled femtosecond optical frequency comb is demonstrated in this paper. We stabilized carrier envelope offset frequency onto a RF reference and obtained the in-loop frequency instability is about 4.3×10-18@1s. We stabilized repetition rate onto an ultrastable laser. The relative frequency instability is 5.3 × 10-18@1s.
Combination of Dual-Comb Spectroscopy with Jones-Matrix Polarimetry
Authors: Koresawa Hidenori , Hase Eiji , Tokizane Yu , Minamikawa Takeo , Yasui Takeshi
Published: July 2023

We combine dual-comb spectroscopy with Jones-Matrix polarimetry for rapid, high-precision, and broadband spectroscopic polarimetry benefiting from no polarization modulation techniques.
Digital Holographic Reconstruction of a Diffusely Reflecting Object Using Single-shot Fresnel Approach
Authors: Ghareab Dahi , Ibrahim Abdelsalam
Published: July 2023

Rough samples are reconstructed using single-shot Fresnel approach. Windowed Fourier filtering (WFF) is used to improve the quality of the reconstructed image. The WFF can be used before or after the reconstruction of the interferogram.
Step Height Measurement via Vortex Beam Diffraction
Authors: Banguilan Dina Grace C. , Hermosa Nathaniel P.
Published: July 2023

We measure the height of a single reflective step through vortex beam diffraction by a triangular aperture. By calculating the SSIM index between the patterns, we can identify theoretically within 0 to λ/4 height difference.
Broadband UV Confocal Spectroscopy and its applications
Authors: Lu Guo-Hao , Liu Chao-Feng , Weng Chun-Jen
Published: July 2023

This paper reports on the integration of a broadband light source with reflective optics to enable broadband UV confocal spectroscopy across a bandwidth of 250 nm to 1100 nm. This paper focuses on the performance of the confocal system and characteristic of AR-coated GRIN lens.
Conditional uncertainties of two-path interferences
Authors: Kuroki Shunichi , Matsushita Tomonori , Iinuma Masataka , Hofmann Holger F.
Published: July 2023

The uncertainties in the path of a single photon conditioned by the outcome of an interference experiment can be observed using small polarization rotations. Constructive and destructive interferences correspond to different distributions between the paths.
On the Constraints in Convex Optimization to Estimate POVM Elements of a Photon-Number-Resolving Detector from Coherent-State Inputs
Authors: Yoshizawa Akio , Fukuda Daiji
Published: July 2023

Smoothing regulation in constrained convex optimization is numerically studied to well estimate POVM elements of a photon-number-resolving detector from coherent-state inputs. Smoothing itself should be optimized with the detection efficiency in mind.
A Silicon Thermo-optic Switch With Sub-10 mW Switching Power And Sub-10 µs Switching Time
Authors: Lin Dongdong , Yun Binfeng
Published: July 2023

We demonstrated a spiral silicon waveguide optical switch with optimized pulse driving. The switching power and the switching time are 8.73 mW and 5 µs separately.
High-density non-Hermitian photonic integrated circuits
Authors: Wei Yanxian , Zhou Hailong , Ding Yunhong , Dong Jianji , Zhang Xinliang
Published: July 2023

In this paper, we make use of the non-Hermitian system to construct high density integrated waveguide array. An extinct ratio of 15 dB is observed at a gap spacing of 400 nm.
Graphene Thermal Emitters Directly Grown on Chips by Etching-Precipitation Method
Authors: Shimura Yui , Matano Shinichiro , Nakagawa Kenta , Noda Suguru , Maki Hideyuki
Published: July 2023

We have demonstrated a blackbody micro-emitter using etching-precipitation graphene that requires no transfer process. Long-lifetime and bright emission are achieved by using a bow-tie-shaped graphene. This graphene-based micro-emitter is expected to be applied to integrated photonics and optoelectronics.
Noise Reduction by Differential Detection for Mid-infrared Laser Spectroscopy
Authors: Nagasaka Kyosuke , Sugiyama Atsushi , Akikusa Naota , Edamura Tadataka
Published: July 2023

Differential detection technique was applied to mid-infrared laser spectroscopy with use of MOEMS-based wavelength swept/tunable quantum cascade laser. It was found that the noise reduction effect was 3.8 times higher than the method without differential detection. We demonstrated transmission spectrum measurement of methane (CH4) over 200 cm-1 (7.14 pm to 8.34 µm).
Temperature-insensitive measurement of refractive index using a no-core fiber-based modal interferometer
Authors: Kim Taeyoon , Jung Junha , Lim Geun Weon , Lee Ju Han
Published: July 2023

We demonstrate a temperature-insensitive refractive index (RI) sensor based on an SMF-NCF-SMF structure-based modal interferometer with a wave configuration. The RI measurement sensitivity of our proposed refractometer was ~-53.24nm/RIU with no temperature sensitivity (0 pm/°C).
A Terahertz Metasurface based Refractive Index Sensor
Authors: Aruna Gandhi M. S. , Nagarajan N. , Singhal Rahul , Li Qian
Published: July 2023

The proposed dual-layer highly coupled patch metasurface terahertz sensor achieves a maximum sensitivity of 0.65 THz/RIU, figure-of-merit of 1.828 RIU-1 in the sample refractive-index from 1.6-1.7, with quality factor of 6.3 for the bio-chemical applications.
Reflected-Phase Measurement of Azimuth-Rotated Guided-Mode Resonance Device Using Pohl Interferometer
Authors: Chang Cheng-Tsung , Tongpakpanang Jaturon , Kuo Wen-Kai
Published: July 2023

Phase interrogation of a guided-mode resonance (GMR) device has a better noise immunity than intensity-type interrogations. In this paper, we report the reflected-phase measurement results of the GMR device using the Pohl interferometer. Fringe shifts of the interferogram caused by the abrupt phase change of the resonantly reflected beam were observed by rotating the azimuth angle of the GMR device and without altering the reflected interference beam position, and the fringe shift can be captured and calculated by a fixed position camera. Our results demonstrate that the phase interrogation of the GMR device in sensing applications can be very compact and low-cost.
High Sensitive Pixel with Covered Microlens for Quad Color Filter Array
Authors: Hwang Jae-Hyeok , Kim Yunkyung
Published: July 2023

A covered microlens structure is suggested for high sensitivity of CMOS image sensor with quad color filter (CF) array. We confirmed that the sensitivity of the suggested structure was increased by an optical simulation.
All-Fiber High-Power Chirped Pulse Amplification System at 1.03 µm
Authors: Wang Tao , Li Can , Ren Bo , Guo Kun , Zhou Pu
Published: July 2023

A high-power all-fiber chirped pulse amplification system is experimentally demonstrated. The average power is scaled up to 536.3 W. The pulse duration is compressed to 781 fs at the output power of 154 W.
Microbubbles photothermally induced on sub-wavelength FeSi2 discs
Authors: Namura Kyoko , Hara Ayaka , Suzuki Motofumi
Published: July 2023

Photothermal conversion properties of FeSi2 discs were used to generate water vapor microbubbles. The bubble size depended on the total heat generation because the disc size and the thermal diffusion length were comparable.
Sensing Kinetics of Ice Recrystallization through Plasmonic Nanoantennas
Authors: Park Nu-Ri , Lee Yedam , Kim Han-Na , Lee Sang Yup , Ahn Dong June , Kim Myung-Ki
Published: July 2023

We directly observed the ice recrystallization in real-time within a space of tens of nanometers using plasmonic nanoantennas. At the same time, we were able to elucidate the mechanism of inhibition of ice recrystallization.
Design and Optimization of Epsilon-Near-Zero Multilayer Structures with Broadband Absorption Performance
Authors: Wang Yuqing , Wu Jiaye , Huang Chenxingyu , Xie Ze Tao , Fu H. Y. , Li Qian
Published: July 2023

The absorption bandwidth of the AZO-TiO2 structure is optimized from 483 nm to 628 nm by a modified genetic algorithm. This optimization is appropriate for both normally incident plane waves and obliquely incident polarized waves.
Design of a quantum-dot single-photon source on a silicon nitride waveguide for efficient and indistinguishable photon generation
Authors: Pholsen Natthajuks , Ota Yasutomo , Katsumi Ryota , Arakawa Yasuhiko , Iwamoto Satoshi
Published: July 2023

We design quantum-dot single-photon sources based on a defect-based photonic crystal cavity on a SiN waveguide with >90% efficiency. The defect region secures distance between etched airholes and quantum dots, expected to improve photon indistinguishability.
Optical Communication Systems: Scaling Capacity and Energy
Authors: Winzer Peter J.
Published: July 2023

We discuss the capacity scaling of optical communications from ultra-long-haul subsea cables to ultra-low-power intra-datacenter interconnects and show that massive spatial parallelism is the only sustainable option for the next decade and beyond.
Fluctuation for Nanophotonics
Authors: Kawata Satoshi
Published: July 2023

In the field of nanophotonics, suppression of fluctuations in detectors, light sources, and the environment is an important issue because they cause fatal errors in results. In this talk, I would like to discuss the positive use of fluctuations rather as a signal source, using micro- and nano-Raman imaging and 3D-nanofabrication as examples.
Optimized design of filterless horseshoe networks exploiting point-to-multipoint coherent transceivers
Authors: Hosseini Mohammad M. , Pedro João , Napoli Antonio , Costa Nelson , Prilepsky Jaroslaw E. , Turitsyn Sergei K.
Published: July 2023

The horseshoe topology is widely used to realize metro-aggregation networks, since it provides a natural fit to the hub-and-spoke traffic pattern present in the majority of these deployments, while enabling survivability against single link and hub failures. A filterless architecture can also be adopted to further reduce capital expenditure (CapEx) by replacing active elements, such as reconfigurable add/drop multiplexers, with simpler and passive splitters/combiners. Such an architecture can effectively host coherent-based point-to-multipoint (P2MP) transceivers enabled by digital subcarrier multiplexing (DSCM). Importantly, by carefully optimizing the deployment of amplifiers (location and gain) and splitters/combiners (type), it may be possible to reduce the total number of optical amplifiers required, further decreasing CapEx. This paper proposes an integer linear programming framework to optimize metro-aggregation filterless horseshoe networks, taking into account the specific requirements of DSCM-based P2MP coherent transceivers. The results indicate that a considerable reduction in amplifier count is possible while ensuring that end-to-end performance thresholds are met, which include the minimum required input power at the receivers, a maximum subcarrier input power difference at the hub’s receivers, and the minimum optical-signal-to-noise ratio.
Multi-frequency Doppler-free spectroscopy of cesium using an external cavity diode laser
Authors: Chang Pengyuan , Liu Jingyang , Zhou Xingyu , Li Jian , Wang Xiaomeng , Chen Jingbiao , Wang Qin
Published: July 2023

We employed a different approach to develop multi-frequency saturated-absorption spectroscopy (SAS) involving both cesium hyperfine ground state levels using a multimode external cavity diode laser (ECDL), which could operate with neither another independent laser nor a modulator. The multi-frequency SAS is formed by atomic velocity groups on resonance with both of the laser modes from an ECDL in multimode operation, which are counterpropagated through the vapor cell as a quasicoherent pair of laser beams. A sign reversal of the sub-Doppler resonance under special pump–probe polarization with and without applied magnetic fields is observed. Simultaneously, the optical microwave generation of the multimode ECDL is also investigated experimentally. The free-running linewidth of the beat note spectra between two modes is about 475 Hz, which indicates a high coherence between them. This oscillator- and modulator-free approach provides a complementary scheme for existing optical microwave generation and has potential for improvements.
Fluorescence lifetime measurements using photon pair correlations generated via spontaneous parametric down conversion (SPDC)
Authors: Eshun Audrey , Yi Xiyu , Wilson Ashleigh , Jeppson Sam , Yoo Jae Hyuck , Kiannejad Shervin , Rushford Mike , Bond Tiziana , Laurence Ted
Published: July 2023

We have used photon pair correlations generated via spontaneous parametric downconversion (SPDC) to measure the fluorescence lifetime of the organic dye rhodamine 6 G, demonstrating that fluorescence lifetime measurements can be achieved using a continuous wave (CW) laser, without pulsed or modulated lasers. Our entangled photon method, quantum fluorescence lifetime (Q-FL) measurements, uses one photon to excite fluorescence and the resulting fluorescence photon is timed and referenced to the arrival time of the other entangled photon. Thus, we can exploit the short timescale of photon pair correlations to conduct experiments that are typically carried out with pulsed lasers and we show that the inherent timing of the photons is fast enough to resolve the nanosecond scale fluorescence lifetime of the sample. This measurement paves the way towards using the time correlations of entangled photons for fluorescence imaging; capitalizing on the presence of fast, sub-100 ps correlations that have not been demonstrated classically.
Enhancement of quantum cascade laser intersubband transitions via coupling to resonant discrete photonic modes of subwavelength gratings
Authors: Mikulicz Monika , Rygała Michał , Smołka Tristan , Janczak Mikołaj , Badura Mikołaj , Łozińska Adriana , Wolf Adriana , Emmerling Monika , Ściana Beata , Höfling Sven , Czyszanowski Tomasz , Sęk Grzegorz , Motyka Marcin
Published: July 2023

We present an optical spectroscopic study of InGaAs/AlInAs active region of quantum cascade lasers grown by low pressure metal organic vapor phase epitaxy combined with subwavelength gratings fabricated by reactive ion etching. Fourier-transformed photoluminescence measurements were used to compare the emission properties of structures before and after processing the gratings. Our results demonstrate a significant increase of the photoluminescence intensity related to intersubband transitions in the mid-infrared, which is attributed to coupling with the grating modes via so called photonic Fano resonances. Our findings demonstrate a promising method for enhancing the emission in optoelectronic devices operating in a broad range of application-relevant infrared.
Low-loss and broadband polarization-diversity edge coupler on a thin-film lithium niobate platform
Authors: Chen Gengxin , Chen Kaixuan , Yu Zejie , Liu Liu
Published: July 2023

Fiber-to-chip coupling is an essential issue for taking high-performance integrated photonic devices into practical applications. On a thin-film lithium niobate platform, such a high-performance coupler featuring low loss, large bandwidth, and polarization independence is highly desired. However, the mode hybridization induced by the birefringence of lithium niobate seriously restricts a polarization-independent coupling. Here, we propose and experimentally demonstrate a high-performance and polarization-diversity cantilever edge coupler (EC) with the assistance of a two-stage polarization splitter and rotator (PSR). The fabricated cantilever EC shows a minimal coupling loss of 1.06 dB/facet, and the fully etched PSR structure shows a low insertion loss (IL) of −0.62 dB. The whole polarization-diversity cantilever EC exhibits a low IL of −2.17 dB and −1.68 dB for TE0 and TM0 mode, respectively, as well as a small cross talk of <−15 dB covering the wavelength band from 1.5 µm to 1.6 µm. A polarization-dependent loss <0.5 dB over the same wavelength band is also obtained. The proposed fiber-to-waveguide coupler, compatible with the fabrication process of popular thin-film lithium niobate photonic devices, can work as a coupling scheme for on-chip polarization-diversity applications.
Absolute measurement of focusing properties of a large-aperture diffractive lens
Authors: Cai Zhiqian , Zhang Junyong , Yang Pengqian , Zhu Jianqiang
Published: July 2023

Diffractive lenses are popular in large optical systems owing to their lightweight and multifunctional design. However, they are difficult to calibrate accurately due to the cross talk between the first-order diffraction and the background light. Here, a quadriwave lateral shearing interferometry (QWLSI) with spherical wave illumination was proposed to absolutely measure the focusing properties of diffractive lenses by means of the reference background light, in which the corresponding theoretical modeling was first derived, and then the single-shot experiment on a 210 mm-diameter beam was carried out. The results showed that the measurement error of the focal length was 0.59%, and the consistency error was 0.008%.
The impact of a combined TB/HIV intervention on the incidence of TB infection among adolescents and young adults in the HPTN 071 (PopART) trial communities in Zambia and South Africa
Authors: Shanaube Kwame , Schaap Ab , Mureithi Linda , Amofa-Sekyi Modupe , Paulsen Robynn , Cheeba Maina , Kangololo Bxyn , Vermaak Redwaan , Sisam Carmen , Kosloff Barry , de Haas Petra , Fidler Sarah , Ruperez Maria , Hayes Richard , Floyd Sian , Ayles Helen ,   on behalf of the TREATS Study Team
Published: July 2023

Background

HPTN071 (PopART) was a cluster randomized trial conducted in Zambian and South African (SA) communities, between 2013–2018. The PopART intervention (universal HIV-testing and treatment (UTT) combined with population-level TB symptom screening) was implemented in 14 communities. The TREATS study (2017–2021) was conducted to evaluate the impact of the PopART intervention on TB outcomes. We report on the impact of the combined TB/HIV intervention on the incidence of TB infection in a cohort of adolescents and young adults (AYA) aged 15–24 years.

Methods

A random sample of AYA was enrolled between July 2018 and July 2019 in 7 intervention vs 7 standard-of-care communities. We collected questionnaire data on risk factors for TB, and blood for measuring TB infection using QuantiFERON (QFT) Plus. AYA were seen at months 12 and 24 with all procedures repeated. Primary outcome was incidence of TB infection comparing intervention and standard-of-care communities. An incident case was defined as a participant with QFT interferon-gamma response of < 0.2 IU/ml plasma (‘negative’) at baseline and a QFT interferon-gamma response of > = 0.7 IU/ml (‘positive’) at follow up.

Results

We enrolled 4,648 AYA, 2,223 (47.8%) had a negative QFT-plus result at baseline, 1,902 (85.6%) had a follow up blood sample taken at 12 months or 24 months. Among the 1,902 AYA, followed for 2,987 person-years, 213 had incident TB infection giving (7.1 per 100 person-years). TB infection incidence rates were 8.7 per 100 person-years in intervention communities compared to 6.0 per 100 person-years in standard-of-care communities. There was no evidence the intervention reduced the transmission of TB (incidence-rate-ratio of 1.45, 95%CI 0.97–2.15, p = 0.063).

Conclusion

In our trial setting, we found no evidence that UTT combined with TB active case finding reduced the incidence of TB infection at population level. Our data will inform future modelling work to better understand the population level dynamics of HIV and TB.
Social and clinical risk factors associated with hospitalized COVID-19 patients in Brussels’s deprived and multiethnic areas
Authors: Racape Judith , Noel Anne-Cecile , Lurel Jerome , Dauby Nicolas , Coppieters Yves , Goffard Jean-Christophe , Rea Andrea
Published: July 2023

Background

In Belgium, the Brussels-Capital region was severely affected by the COVID-19 epidemic. Various hypotheses were mentioned in order to explain Brussels’ excess disease spreading and mortality rate, but socioeconomic risk factors are increasingly recognized. This study’s objective was to analyze clinical and social profiles of patients hospitalized for COVID-19, by nationality groups, in two hospitals located in Brussels’s deprived and multiethnic areas.

Methods

Data covered hospitalized COVID-19 patients from two Brussels hospitals (n = 787) between the 1st of March 2020 and the 31st of June 2020. Social data was collected using hospital records, and clinical data was extracted from hospitals’ COVID-19 databases. Multivariable logistic regression models were used to estimate the odds ratios (OR) of the association between two outcomes (Intensive Care Unit admission and mortality) and risk factors (social and clinical).

Results

Patients from Sub-Saharan Africa were younger, had a higher prevalence of obesity, lacked health insurance, and had the highest proportion of Intensive Care Unit (ICU) admission (27.7%) but the lowest mortality rates than other nationality groups. Patients from North Africa had a higher prevalence of diabetes compared to other nationality groups and a high proportion of European patients came from nursing homes. Patients deprived of health insurance had a higher risk of ICU admission compared to those who had insurance (OR IC95%; 1,9 1.1–3.6, p = 0.03). Other risk factors as sex and obesity were significantly associated to ICU admission and, age and hypertension were significantly associated to mortality.

Conclusion

Social and clinical profile of the patients differs between the nationality groups, and some risk factors for Intensive Care Unit admission and mortality were linked to more patients’ precarious situation as the availability of health insurance. This study underlines the role of selected social health determinants and the importance of routinely collecting social along with clinical data.
Supply chain finance and innovation efficiency: An empirical analysis based on manufacturing SMEs
Authors: Wang Qiang , Yuan Shichao , Ostic Dragana , Pan Liujun
Published: July 2023

This paper firstly demonstrates the positive and negative effects of supply chain finance on the innovation efficiency of China’s small and medium-sized enterprises (SMEs) in the manufacturing industry from the theoretical point of view. Based on the data of 267 manufacturing companies in China Growth Enterprise Market from 2015 to 2019, the DEA-SBM method was used to measure the comprehensive innovation efficiency of different companies, and it was further decomposed into technological innovation efficiency and organizational innovation efficiency. Afterwards, it conducts an empirical analysis through the double fixed effect model, and explores the difference in the impact of supply chain finance on innovation efficiency in enterprises with different industries and different property rights. The results show that supply chain financial services have a strong positive impact on the comprehensive innovation efficiency, technological innovation efficiency and organizational innovation efficiency of manufacturing SMEs. Further, supply chain finance has the most significant improvement on the technological innovation efficiency of the sample of private traditional enterprises, but it has a significant inhibitory effect on the organizational innovation efficiency of the sample of state-owned high-tech enterprises. Therefore, this paper suggests that the development of supply chain financial services should increase support for traditional manufacturing industries; appropriately tilt resources to private enterprises; improve relevant supply chain financial laws and regulations, establish and improve corresponding institutional arrangements, and encourage state-owned enterprises to participate in market competition.
Diabetes self-management education interventions and self-management in low-resource settings; a mixed methods study
Authors: Lamptey Roberta , Amoakoh-Coleman Mary , Djobalar Babbel , Grobbee Diederick E. , Adjei George Obeng , Klipstein-Grobusch Kerstin
Published: July 2023

Introduction

Diabetes is largely a self-managed disease; thus, care outcomes are closely linked to self-management behaviours. Structured self-management education (DSME) interventions are, however, largely unavailable in Africa.

Aim

We sought to characterise DSME interventions in two urban low-resource primary settings; and to explore diabetes self-management knowledge and behaviours, of persons living with diabetes (PLD).

Research design and methods

A convergent parallel mixed-methods study was conducted between January and February 2021 in Accra, Ghana. The sampling methods used for selecting participants were total enumeration, consecutive sampling, purposive and judgemental sampling. Multivariable regression models were used to study the association between diabetes self-management knowledge and behaviours. We employed inductive content analysis of informants’ experiences and context, to complement the quantitative findings.

Results

In total, 425 PLD (70.1% (n = 298) females, mean age 58 years (SD 12), with a mean blood glucose of 9.4 mmol/l (SD 6.4)) participated in the quantitative study. Two managers, five professionals, two diabetes experts and 16 PLD participated in in-depth interviews. Finally, 24 PLD were involved in four focus group discussions. The median diabetes self-management knowledge score was 40% ((IQR 20–60). For every one unit increase in diabetes self-management knowledge, there were corresponding increases in the diet (5%;[95% CI: 2%-9%,p<0.05]), exercise (5%; [95% CI:2%-8%,p<0.05]) and glucose monitoring (4%;[95% CI:2%-5%,p<0.05]) domains of the diabetes self-care activities scale respectively. The DSME interventions studied, were unstructured and limited by resources. Financial constraints, conflicting messages, beliefs, and stigma were the themes underpinning self-management behaviour.

Conclusions

The DSME interventions studied were under-resourced, and unstructured. Diabetes self-management knowledge though limited, was associated with self-management behaviour. DSME interventions in low resource settings should be culturally tailored and should incorporate sessions on mitigating financial constraints. Future studies should focus on creating structured DSME interventions suited to resource-constrained settings.
Dynamic susceptibility contrast perfusion-weighted and diffusion-weighted magnetic resonance imaging findings in pilocytic astrocytoma and H3.3 and H3.1 variant diffuse midline glioma, H3K27-altered
Authors: Kurokawa Ryo , Kurokawa Mariko , Baba Akira , Kim John , Srinivasan Ashok , Moritani Toshio
Published: July 2023

Objective

This study compared the dynamic susceptibility contrast (DSC) magnetic resonance imaging parameters and apparent diffusion coefficient (ADC) between pilocytic astrocytoma (PA) and diffuse midline glioma, H3K27-altered (DMG) variants.

Methods

The normalized relative cerebral blood volume (nrCBV), normalized relative flow (nrCBF), percentile signal recovery (PSR), and normalized mean ADC (nADCmean) of 23 patients with midline PAs (median age, 13 years [range, 1–71 years]; 13 female patients) and 40 patients with DMG (8.5 years [1–35 years]; 19 female patients), including 35 patients with H3.3- and five patients with H3.1-mutant tumors, treated between January 2016 and May 2022 were statistically compared.

Results

DMG had a significantly lower nADCmean (median: 1.48 vs. 1.96; p = 0.00075) and lower PSR (0.97 vs. 1.23, p = 0.13) but higher nrCBV and nrCBF (1.66 vs. 1.17, p = 0.058, respectively, and 1.87 vs. 1.19, p = 0.028, respectively) than PA. The H3.3 variant had a lower nADCmean than the H3.1 variant (1.46 vs. 1.80, p = 0.10).

Conclusion

DMG had lower ADC and PSR and higher rCBV and rCBF than PA. The H3.3 variant had a lower ADC than the H3.1 variant. Recognizing the differences and similarities in the DSC parameters and ADC between these tumors may help presurgical diagnosis.
Investigation into relationships between design parameters and mechanical properties of 3D printed PCL/nHAp bone scaffolds
Authors: Yazdanpanah Zahra , Kumar Sharma Nitin , Zimmerling Amanda , Cooper David M. L. , Johnston James D. , Chen Xiongbiao
Published: July 2023

Background

Scaffolds are of great importance in tissue engineering applications as they provide a mechanically supportive environment for cellular activity, which is particularly necessary for hard tissues such as bone. Notably, the mechanical properties of a scaffold vary with differing design parameters such as those related to scaffold height and internal structure. Thus, the present study aimed to explore the relationship between design parameters and mechanical properties of composite polycaprolactone (PCL) and nano-hydroxyapatite (nHAp) scaffolds fabricated by three-dimensional (3D) printing.

Methods

We designed and printed scaffolds with different internal structures (lattice and staggered) and varying heights (4, 6, 8 and 10 layers), and consistent porosity (50%) for the purpose of comparison. Then, we examined the scaffold microstructure (pore size and penetration between layers) using scanning electron microscopy (SEM) and mechanical properties (elastic modulus and yield strength) using compressive testing.

Results

Our results illustrated that the microstructural parameters were related to scaffold design. At higher heights, pore size increased while penetration between layers decreased; thus, mechanical properties were affected. Results of mechanical testing demonstrated that for lattice scaffolds, elastic modulus was similar for 6 vs 4, and 8 vs 4 layers but ~33% lower for 10 layers vs 4 layers. Similarly, yield strength was comparable for 6 vs 4, and 8 vs 4 layers but ~27% lower for 10 layers vs 4 layers. With staggered scaffolds, when compared to 4-layer results, elastic modulus was similar for 6 layers but was ~43% lower for 8 layers and ~38% lower for 10 layers. Staggered scaffolds had ~38%, ~51%, and ~76% lower yield strength when the number of layers were increased from 4 to 6, 8, and 10 layers, respectively. When comparing lattice and staggered scaffolds with the same layer number, elastic modulus was similar, apart from 8-layer scaffolds where the staggered design was ~42% lower than lattice. Yield strength was similar between 4-layer staggered and lattice scaffolds, while staggered scaffolds with 6, 8, and 10 number of layers showed ~43%, ~45%, ~68% lower strength, respectively, than those found in lattice scaffolds with the same layer numbers.

Conclusions

Mechanical properties of 3D printed scaffolds depended on scaffold height for both lattice and staggered internal structures. Staggered scaffolds had lower mechanical properties than the lattice scaffolds with the same height and were more sensitive to the change in scaffold height. Taken together, lattice scaffolds demonstrated the advantages of more stable mechanical properties over staggered scaffolds. Also, scaffolds with lower height were more promising in terms of mechanical properties compared to scaffolds with greater height.
Morpho-agronomic variability of okra [Abelmoschus esculentus (L.) Moench] genotypes in Dire Dawa, eastern Ethiopia
Authors: Kenaw Wubadis , Mohammed Wassu , Woldetsadik Kebede
Published: July 2023

A total of 21 okra genotypes were evaluated for 25 morpho-agronomic traits in 2020 at Dire Dawa, Ethiopia in a randomized complete block design with three replications. Analysis of variance showed significant differences at p<0.05 level of significance for all traits. Estimates of genotypic (GCV) and phenotypic (PCV) coefficients of variation range from 9.16 to 42.3% and 9.33 to 44.16%, respectively. Heritability in a broad sense (H2) and genetic advance as a percent of the mean (GAM) ranged from 29.57 to 91.89% and 10.39 to 83.53%, respectively. Estimated variability components (GCV, PCV, H2, and GAM) were high and moderate for all traits except days to 50% emergence 9.33% of GCV and PCV, internode length 9.16% of GCV and green fruit width 29.57% of H2 that were categorized under low. The first four principal component axes (PCA1 to PCA4) accounted for 7.83 to 35.02%, which accounted 74.56% of the total variability with eigenvalues that ranged from 1.95 to 8.75. Genetic distances estimated by Euclidean distance from the 25 traits ranged from 2.33 to 12.56 with a mean of 6.83, standard deviation of 1.8, and a coefficient of variation of 26.46%. The genotypes were grouped into four distinct clusters using the Euclidean distance matrix using UPGMA. Indigenous okra genotypes collected from Ethiopia were more divergent with high genetic distances and had a higher performance for most of the traits including growth, green fruit yield, and seed yield than introduced genotypes. In conclusion, this study showed the presence of variation among genotypes for most of the traits, indicating that selection of genotypes could be effective to develop okra varieties with high green fruit and seed yield through direct selection or crossing.