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Non-volatile dynamically switchable color display via chalcogenide stepwise cavity resonators 被引量:1
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作者 Kuan Liu Zhenyuan Lin +2 位作者 Bing Han Minghui Hong Tun Cao 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第1期16-27,共12页
High-resolution multi-color printing relies upon pixelated optical nanostructures,which is crucial to promote color display by producing nonbleaching colors,yet requires simplicity in fabrication and dynamic switching... High-resolution multi-color printing relies upon pixelated optical nanostructures,which is crucial to promote color display by producing nonbleaching colors,yet requires simplicity in fabrication and dynamic switching.Antimony trisulfide(Sb_(2)S_(3))is a newly rising chalcogenide material that possesses prompt and significant transition of its optical characteristics in the visible region between amorphous and crystalline phases,which holds the key to color-varying devices.Herein,we proposed a dynamically switchable color printing method using Sb_(2)S_(3)-based stepwise pixelated Fabry-Pérot(FP)cavities with various cavity lengths.The device was fabricated by employing a direct laser patterning that is a less timeconsuming,more approachable,and low-cost technique.As switching the state of Sb_(2)S_(3) between amorphous and crystalline,the multi-color of stepwise pixelated FP cavities can be actively changed.The color variation is due to the profound change in the refractive index of Sb_(2)S_(3) over the visible spectrum during its phase transition.Moreover,we directly fabricated sub-50 nm nano-grating on ultrathin Sb_(2)S_(3) laminate via microsphere 800-nm femtosecond laser irradiation in far field.The minimum feature size can be further decreased down to~45 nm(λ/17)by varying the thickness of Sb_(2)S_(3) film.Ultrafast switchable Sb_(2)S_(3) photonic devices can take one step toward the next generation of inkless erasable papers or displays and enable information encryption,camouflaging surfaces,anticounterfeiting,etc.Importantly,our work explores the prospects of rapid and rewritable fabrication of periodic structures with nano-scale resolution and can serve as a guideline for further development of chalcogenide-based photonics components. 展开更多
关键词 TUNABLE color displays Fabry-Pérot cavity resonators color printing chalcogenide materials
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Tunable superconducting resonators via on-chip control of local magnetic field
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作者 王晨光 岳文诚 +13 位作者 涂学凑 迟天圆 郭婷婷 吕阳阳 董思宁 曹春海 张蜡宝 贾小氢 孙国柱 康琳 陈健 王永磊 王华兵 吴培亨 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期674-679,共6页
Superconducting microwave resonators play a pivotal role in superconducting quantum circuits.The ability to finetune their resonant frequencies provides enhanced control and flexibility.Here,we introduce a frequency-t... Superconducting microwave resonators play a pivotal role in superconducting quantum circuits.The ability to finetune their resonant frequencies provides enhanced control and flexibility.Here,we introduce a frequency-tunable superconducting coplanar waveguide resonator.By applying electrical currents through specifically designed ground wires,we achieve the generation and control of a localized magnetic field on the central line of the resonator,enabling continuous tuning of its resonant frequency.We demonstrate a frequency tuning range of 54.85 MHz in a 6.21-GHz resonator.This integrated and tunable resonator holds great potential as a dynamically tunable filter and as a key component of communication buses and memory elements in superconducting quantum computing. 展开更多
关键词 superconducting resonator NBN kinetic inductance tunable resonator
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Octave-spanning Kerr soliton frequency combs in dispersion-and dissipation-engineered lithium niobate microresonators
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作者 Yunxiang Song Yaowen Hu +2 位作者 Xinrui Zhu Kiyoul Yang Marko Lončar 《Light(Science & Applications)》 SCIE EI CSCD 2024年第10期2342-2352,共11页
Dissipative Kerr solitons from optical microresonators,commonly referred to as soliton microcombs,have been developed for a broad range of applications,including precision measurement,optical frequency synthesis,and u... Dissipative Kerr solitons from optical microresonators,commonly referred to as soliton microcombs,have been developed for a broad range of applications,including precision measurement,optical frequency synthesis,and ultrastable microwave and millimeter wave generation,all on a chip.An important goal for microcombs is self-referencing,which requires octave-spanning bandwidths to detect and stabilize the comb carrier envelope offset frequency.Further,detection and locking of the comb spacings are often achieved using frequency division by electro-optic modulation.The thin-film lithium niobate photonic platform,with its low loss,strong second-and third-order nonlinearities,as well as large Pockels effect,is ideally suited for these tasks.However,octave-spanning soliton microcombs are challenging to demonstrate on this platform,largely complicated by strong Raman effects hindering reliable fabrication of soliton devices.Here,we demonstrate entirely connected and octave-spanning soliton microcombs on thin-film lithium niobate.With appropriate control over microresonator free spectral range and dissipation spectrum,we show that soliton-inhibiting Raman effects are suppressed,and soliton devices are fabricated with near-unity yield.Our work offers an unambiguous method for soliton generation on strongly Raman-active materials.Further,it anticipates monolithically integrated,self-referenced frequency standards in conjunction with established technologies,such as periodically poled waveguides and electro-optic modulators,on thin-film lithium niobate. 展开更多
关键词 MILLIMETER SOLITON resonator
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Single 5-nm quantum dot detection via microtoroid optical resonator photothermal microscopy
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作者 Shuang Hao Sartanee Suebka Judith Su 《Light(Science & Applications)》 SCIE EI CSCD 2024年第10期2145-2155,共11页
Label-free detection techniques for single particles and molecules play an important role in basic science,disease diagnostics,and nanomaterial investigations.While fluorescence-based methods are tools for single mole... Label-free detection techniques for single particles and molecules play an important role in basic science,disease diagnostics,and nanomaterial investigations.While fluorescence-based methods are tools for single molecule detection and imaging,they are limited by available molecular probes and photoblinking and photobleaching.Photothermal microscopy has emerged as a label-free imaging technique capable of detecting individual nanoabsorbers with high sensitivity.Whispering gallery mode(WGM)microresonators can confine light in a small volume for enhanced light-matter interaction and thus are a promising ultra-sensitive photothermal microscopy platform.Previously,microtoroid optical resonators were combined with photothermal microscopy to detect 250 nm iong gold nanorods and 100 nm long polymers.Here,we combine microtoroids with photothermal microscopy to spatially detect single 5 nm diameter quantum dots(QDs)with a signal-to-noise ratio exceeding 10*.Photothermal images were generated by point-by-point scanning of the pump laser.Single particle detection was confrmed for 18 nm QDs by high sensitivity fluorescence imaging and for 5 nm QDs via comparison with theory.Our system demonstrates the capability to detect a minimum heat dissipation of o.75 pW.To achieve this,we integrated our microtoroid based photothermal microscopy setup with a low amplitude modulated pump laser and utilized the proportional-integral-derivative controller output as the photothermal signal source to reduce noise and enhance signal stability.The heat dissipation of these QDs is below that from single dye molecules.We anticipate that our work will have application in a wide variety of fields,including the biological sciences,nanotechnology,materials science,chemistry and medicine. 展开更多
关键词 PUMP resonator QUANTUM
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Layered metastructure containing freely-designed local resonators for wave attenuation
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作者 Yu Li Huguang He +3 位作者 Jiang Feng Hailong Chen Fengnian Jin Hualin Fan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期23-31,共9页
Combining periodic layered structure with three-dimensional cylindrical local resonators,a hybrid metastructure with improved wave isolation ability was designed and investigated through theoretical and numerical appr... Combining periodic layered structure with three-dimensional cylindrical local resonators,a hybrid metastructure with improved wave isolation ability was designed and investigated through theoretical and numerical approaches.The metastructure is composed of periodic rubber layers and concrete layers embedded with three-dimensional resonators,which can be freely designed with multi local resonant frequencies to attenuate vibrations at required frequencies and widen the attenuation bandgap.The metastructure can also effectively attenuate seismic responses.Compared with layered rubber-based structures,the metastructure has more excellent wave attenuation effects with greater attenuation and wider bandgap. 展开更多
关键词 Layered metastructure Local resonator Wave attenuation
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Asymmetrical Fabry-Perot cavity slot micro-ring resonator and its sensing characteristics
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作者 CAO Qianqian LIU Chunjuan +1 位作者 WU Xiaosuo SUN Xiaoli 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期292-301,共10页
To achieve high quality factor and high-sensitivity refractive index sensor,a slot micro-ring resonator(MRR)based on asymmetric Fabry-Perot(FP)cavity was proposed.The structure consisted of a pair of elliptical holes ... To achieve high quality factor and high-sensitivity refractive index sensor,a slot micro-ring resonator(MRR)based on asymmetric Fabry-Perot(FP)cavity was proposed.The structure consisted of a pair of elliptical holes to form an FP cavity and a microring resonator.The two different optical modes generated by the micro-ring resonator were destructively interfered to form a Fano line shape,which improved the system sensitivity while obtaining a higher quality factor and extinction ratio.The transmission principle of the structure was analyzed by the transfer matrix method.The transmission spectrum and mode field distribution of the proposed structure were simulated by the finite difference time domain(FDTD)method,and the key structural parameters affecting the Fano line shape in the device were optimized.The simulation results show that the quality factor of the device reached 22037.1,and the extinction ratio was 23.9 dB.By analyzing the refractive index sensing characteristics,the sensitivity of the structure was 354 nm·RIU−1,and the detection limit of the sensitivity was 2×10−4 RIU.Thus,the proposed compact asymmetric FP cavity slot micro-ring resonator has obvious advantages in sensing applications owing to its excellent performance. 展开更多
关键词 micro-ring resonator(MRR) Fabry-Perot(FP)cavity Fano resonance refractive index sensing integrated optics silicon waveguide
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Disorder effects in NbTiN superconducting resonators
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作者 吕伟涛 支强 +2 位作者 胡洁 李婧 史生才 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期482-486,共5页
Disordered superconducting materials like NbTiN possess a high kinetic inductance fraction and an adjustable critical temperature, making them a good choice for low-temperature detectors. Their energy gap(D), critical... Disordered superconducting materials like NbTiN possess a high kinetic inductance fraction and an adjustable critical temperature, making them a good choice for low-temperature detectors. Their energy gap(D), critical temperature(T_(c)),and quasiparticle density of states(QDOS) distribution, however, deviate from the classical BCS theory due to the disorder effects. The Usadel equation, which takes account of elastic scattering, non-elastic scattering, and electro–phonon coupling,can be applied to explain and describe these deviations. This paper presents numerical simulations of the disorder effects based on the Usadel equation to investigate their effects on the △, Tc, QDOS distribution, and complex conductivity of the NbTiN film. Furthermore, NbTiN superconducting resonators with coplanar waveguide(CPW) structures are fabricated and characterized at different temperatures to validate our numerical simulations. The pair-breaking parameter α and the critical temperature in the pure state T_(c)^(P) of our NbTiN film are determined from the experimental results and numerical simulations. This study has significant implications for the development of low-temperature detectors made of disordered superconducting materials. 展开更多
关键词 effects of disorder NbTiN superconducting film Usadel equation complex conductivity superconducting resonator
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Dielectric Resonator Magnetoelectric Dipole Arrays with Low Cross Polarization,Backward Radiation,and Mutual Coupling for MIMO Base Station Applications
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作者 Song Simin Da Yiran +4 位作者 Qian Bingyi Huang Xiaoyu Chen Xiaoming Li Yingsong Ahmed A.Kishk 《China Communications》 SCIE CSCD 2024年第6期290-304,共15页
Dielectric resonator magnetoelectric dipole(DRMED)arrays with enhanced isolation,reduced cross-polarization,and backward radiation are proposed for base station(BS)applications.The proposed antenna comprises an elevat... Dielectric resonator magnetoelectric dipole(DRMED)arrays with enhanced isolation,reduced cross-polarization,and backward radiation are proposed for base station(BS)applications.The proposed antenna comprises an elevated dielectric resonator antenna(DRA)on a small metal plate above a sizeable common ground plane.The DRA is designed in its T Eδ11 mode,acting like a magnetic dipole.The surface current excited by the differential probes flowing on the small ground plane is equivalent to an electric dipole.Since these two equivalent dipoles are orthogonal,they have the magnetoelectric dipole characteristics with reduced backward radiation.Meanwhile,the small ground planes can be treated as decoupling structures to provide a neutralization path to cancel the original coupling path.A linearly-polarized 4-element prototype array was verified experimentally in previous work.Here,a dual-polarized DRMED antenna is presented to construct a 2-element and 4×4 array for BS applications.To investigate its MIMO performance,sophisticated multi-cell scenario simulations are carried out.By using the proposed dualpolarized DRMED array,the cellular system capacityis improved by 118.6%compared to a conventional DRA array.This significant MIMO system improvement is mainly due to the reduced backward radiation and,therefore,reduced inter-cell interferences.Measurements align well with the simulations. 展开更多
关键词 backward radiation dielectric resonator antennas(DRAs) isolation magnetoelectric-dipole(ME-dipole)antennas
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Application of the N + 2 Transversal Network Method to the Study of a Coupled Resonator Filter
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作者 Charmolavy Goslavy Lionel Nkouka Moukengue Conrad Onésime Oboulhas Tsahat +2 位作者 Haroun Abba Labane Barol Mafouna Kiminou Achille Makouka 《Open Journal of Applied Sciences》 2024年第6期1412-1424,共13页
This paper presents a new approach to synthesize admittance function polynomials and coupling matrices for coupled resonator filters. The N + 2 transversal network method is applied to study a coupled resonator f... This paper presents a new approach to synthesize admittance function polynomials and coupling matrices for coupled resonator filters. The N + 2 transversal network method is applied to study a coupled resonator filter. This method allowed us to determine the polynomials of the reflection and transmission coefficients. A study is made for a 4 poles filter with 2 transmission zeros between the N + 2 transversal network method and the one found in the literature. A MATLAB code was designed for the numerical simulation of these coefficients for the 6, 8, and 10 pole filter with 4 transmission zeros. 展开更多
关键词 resonator Filter Coupling Matrix Transmission Zero Transversal Network Method
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The parallel-plate resonator:An RF probe for MR and MRI studies over a wide frequency range 被引量:1
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作者 Andres Ramírez Aguilera Kevin J.Sanders +1 位作者 Gillian R.Goward Bruce J.Balcom 《Magnetic Resonance Letters》 2023年第4期306-318,共13页
We explore the use of the parallel-plate resonator for the study of thin cuboid samples over a wide range of magnetic resonance frequencies.The parallel-plate resonator functions at frequencies from tens to hundreds o... We explore the use of the parallel-plate resonator for the study of thin cuboid samples over a wide range of magnetic resonance frequencies.The parallel-plate resonator functions at frequencies from tens to hundreds of MHz.Seven parallel-plate resonators are presented and discussed in a frequency range from 8 to 500 MHz.Magnetic resonance experiments were performed on both horizontal and vertical bore magnet systems with lithium and hydrogen nuclei.Parallel-plate radiofrequency(RF)probes are easy to build and easy to optimize.Experiments and simulations showed good sensitivity of the parallel-plate RF probe geometry with a small decrease in sensitivity at higher frequencies. 展开更多
关键词 Parallel-plate resonator Optimization Magnetic resonance/magnetic resonance imaging(MR/MRI) BATTERIES
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Staging liver fibrosis with various diffusion-weighted magnetic resonance imaging models 被引量:1
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作者 Yan-Li Jiang Juan Li +6 位作者 Peng-Fei Zhang Feng-Xian Fan Jie Zou Pin Yang Peng-Fei Wang Shao-Yu Wang Jing Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1164-1176,共13页
BACKGROUND Diffusion-weighted imaging(DWI)has been developed to stage liver fibrosis.However,its diagnostic performance is inconsistent among studies.Therefore,it is worth studying the diagnostic value of various diff... BACKGROUND Diffusion-weighted imaging(DWI)has been developed to stage liver fibrosis.However,its diagnostic performance is inconsistent among studies.Therefore,it is worth studying the diagnostic value of various diffusion models for liver fibrosis in one cohort.AIM To evaluate the clinical potential of six diffusion-weighted models in liver fibrosis staging and compare their diagnostic performances.METHODS This prospective study enrolled 59 patients suspected of liver disease and scheduled for liver biopsy and 17 healthy participants.All participants underwent multi-b value DWI.The main DWI-derived parameters included Mono-apparent diffusion coefficient(ADC)from mono-exponential DWI,intravoxel incoherent motion model-derived true diffusion coefficient(IVIM-D),diffusion kurtosis imaging-derived apparent diffusivity(DKI-MD),stretched exponential model-derived distributed diffusion coefficient(SEM-DDC),fractional order calculus(FROC)model-derived diffusion coefficient(FROC-D)and FROC model-derived microstructural quantity(FROC-μ),and continuous-time random-walk(CTRW)model-derived anomalous diffusion coefficient(CTRW-D)and CTRW model-derived temporal diffusion heterogeneity index(CTRW-α).The correlations between DWI-derived parameters and fibrosis stages and the parameters’diagnostic efficacy in detecting significant fibrosis(SF)were assessed and compared.RESULTS CTRW-D(r=-0.356),CTRW-α(r=-0.297),DKI-MD(r=-0.297),FROC-D(r=-0.350),FROC-μ(r=-0.321),IVIM-D(r=-0.251),Mono-ADC(r=-0.362),and SEM-DDC(r=-0.263)were significantly correlated with fibrosis stages.The areas under the ROC curves(AUCs)of the combined index of the six models for distinguishing SF(0.697-0.747)were higher than each of the parameters alone(0.524-0.719).The DWI models’ability to detect SF was similar.The combined index of CTRW model parameters had the highest AUC(0.747).CONCLUSION The DWI models were similarly valuable in distinguishing SF in patients with liver disease.The combined index of CTRW parameters had the highest AUC. 展开更多
关键词 Liver fibrosis Magnetic resonance imaging Diffusion-weighted magnetic resonance Liver biopsy Significant fibrosis
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Preoperative prediction of perineural invasion of rectal cancer based on a magnetic resonance imaging radiomics model:A dual-center study 被引量:2
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作者 Yan Liu Bai-Jin-Tao Sun +3 位作者 Chuan Zhang Bing Li Xiao-Xuan Yu Yong Du 《World Journal of Gastroenterology》 SCIE CAS 2024年第16期2233-2248,共16页
BACKGROUND Perineural invasion(PNI)has been used as an important pathological indicator and independent prognostic factor for patients with rectal cancer(RC).Preoperative prediction of PNI status is helpful for indivi... BACKGROUND Perineural invasion(PNI)has been used as an important pathological indicator and independent prognostic factor for patients with rectal cancer(RC).Preoperative prediction of PNI status is helpful for individualized treatment of RC.Recently,several radiomics studies have been used to predict the PNI status in RC,demonstrating a good predictive effect,but the results lacked generalizability.The preoperative prediction of PNI status is still challenging and needs further study.AIM To establish and validate an optimal radiomics model for predicting PNI status preoperatively in RC patients.METHODS This retrospective study enrolled 244 postoperative patients with pathologically confirmed RC from two independent centers.The patients underwent preoperative high-resolution magnetic resonance imaging(MRI)between May 2019 and August 2022.Quantitative radiomics features were extracted and selected from oblique axial T2-weighted imaging(T2WI)and contrast-enhanced T1WI(T1CE)sequences.The radiomics signatures were constructed using logistic regression analysis and the predictive potential of various sequences was compared(T2WI,T1CE and T2WI+T1CE fusion sequences).A clinical-radiomics(CR)model was established by combining the radiomics features and clinical risk factors.The internal and external validation groups were used to validate the proposed models.The area under the receiver operating characteristic curve(AUC),DeLong test,net reclassification improvement(NRI),integrated discrimination improvement(IDI),calibration curve,and decision curve analysis(DCA)were used to evaluate the model performance.RESULTS Among the radiomics models,the T2WI+T1CE fusion sequences model showed the best predictive performance,in the training and internal validation groups,the AUCs of the fusion sequence model were 0.839[95%confidence interval(CI):0.757-0.921]and 0.787(95%CI:0.650-0.923),which were higher than those of the T2WI and T1CE sequence models.The CR model constructed by combining clinical risk factors had the best predictive performance.In the training and internal and external validation groups,the AUCs of the CR model were 0.889(95%CI:0.824-0.954),0.889(95%CI:0.803-0.976)and 0.894(95%CI:0.814-0.974).Delong test,NRI,and IDI showed that the CR model had significant differences from other models(P<0.05).Calibration curves demonstrated good agreement,and DCA revealed significant benefits of the CR model.CONCLUSION The CR model based on preoperative MRI radiomics features and clinical risk factors can preoperatively predict the PNI status of RC noninvasively,which facilitates individualized treatment of RC patients. 展开更多
关键词 Rectal cancer Perineural invasion Magnetic resonance imaging Radiomics NOMOGRAM
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Vibration attenuation of meta-mortar with spring-mass resonators
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作者 San-feng Liu Hai-long Chen +4 位作者 Yang Liu Hu-guang He Xi-yue An Feng-nian Jin Hua-lin Fan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第2期11-23,共13页
Metamaterial based on local resonance has excellent vibration attenuation ability in low frequency.In this research,an attempt was performed to make meta-mortar with spring-mass resonators to attenuate vibration and s... Metamaterial based on local resonance has excellent vibration attenuation ability in low frequency.In this research,an attempt was performed to make meta-mortar with spring-mass resonators to attenuate vibration and shock hazards.Single-spring-mass resonators and dual-spring-mass resonators were designed and made using lead or aluminum blocks and SWPB springs encased by PMMA(polymethyl methacrylate)or aluminum frames.These resonators were placed into mortar blocks to make metamortar specimens.Vibration attenuation effect was investigated by sweeping vibration with frequency from 50 Hz to 2000 Hz.All these meta-mortar blocks exhibit excellent vibration attenuation ability in the designed band gaps.With dual-spring-mass resonators,meta-mortar blocks have two distinct vibration attenuation bands. 展开更多
关键词 Meta-mortar Vibration attenuation Spring-mass resonators
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Electrode design for multimode suppression of aluminum nitride tuning fork resonators
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作者 Yi Yuan Qingrui Yang +6 位作者 Haolin Li Shuai Shi Pengfei Niu Chongling Sun Bohua Liu Menglun Zhang Wei Pang 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2023年第4期11-21,共11页
This paper is focused on electrode design for piezoelectric tuning fork resonators.The relationship between the performance and electrode pattern of aluminum nitride piezoelectric tuning fork resonators vibrating in t... This paper is focused on electrode design for piezoelectric tuning fork resonators.The relationship between the performance and electrode pattern of aluminum nitride piezoelectric tuning fork resonators vibrating in the in-plane flexural mode is investigated based on a set of resonators with different electrode lengths,widths,and ratios.Experimental and simulation results show that the electrode design impacts greatly the multimode effect induced from torsional modes but has little influence on other loss mechanisms.Optimizing the electrode design suppresses the torsional mode successfully,thereby increasing the ratio of impedance at parallel and series resonant frequencies(R_(p)/R_(s))by more than 80%and achieving a quality factor(Q)of 7753,an effective electromechanical coupling coefficient(kt_(eff)^(2))of 0.066%,and an impedance at series resonant frequency(R_(m))of 23.6 kΩ.The proposed approach shows great potential for high-performance piezoelectric resonators,which are likely to be fundamental building blocks for sensors with high sensitivity and low noise and power consumption. 展开更多
关键词 Tuning fork MULTIMODE AlN-based resonator Microelectromechanical systems
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Magnetic resonance imaging of extraocular rectus muscles abnormalities in acute acquired concomitant esotropia 被引量:1
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作者 Jia-Yu Chen Li-Rong Zhang +5 位作者 Jia-Wen Liu Jie Hao Hui-Xin Li Qiong-Yue Zhang Zhao-Hui Liu Jing Fu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期119-125,共7页
AIM:To investigate the difference of medial rectus(MR)and lateral rectus(LR)between acute acquired concomitant esotropia(AACE)and the healthy controls(HCs)detected by magnetic resonance imaging(MRI).METHODS:A case-con... AIM:To investigate the difference of medial rectus(MR)and lateral rectus(LR)between acute acquired concomitant esotropia(AACE)and the healthy controls(HCs)detected by magnetic resonance imaging(MRI).METHODS:A case-control study.Eighteen subjects with AACE and eighteen HCs were enrolled.MRI scanning data were conducted in target-controlled central gaze with a 3-Tesla magnetic resonance scanner.Extraocular muscles(EOMs)were scanned in contiguous image planes 2-mm thick spanning the EOM origins to the globe equator.To form posterior partial volumes(PPVs),the LR and MR cross-sections in the image planes 8,10,12,and 14 mm posterior to the globe were summed and multiplied by the 2-mm slice thickness.The data were classified according to the right eye,left eye,dominant eye,and non-dominant eye,and the differences in mean cross-sectional area,maximum cross-sectional area,and PPVs of the MR and LR muscle in the AACE group and HCs group were compared under the above classifications respectively.RESULTS:There were no significant differences between the two groups of demographic characteristics.The mean cross-sectional area of the LR muscle was significantly greater in the AACE group than that in the HCs group in the non-dominant eyes(P=0.028).The maximum cross-sectional area of the LR muscle both in the dominant and non-dominant eye of the AACE group was significantly greater than the HCs group(P=0.009,P=0.016).For the dominant eye,the PPVs of the LR muscle were significantly greater in the AACE than that in the HCs group(P=0.013),but not in the MR muscle(P=0.698).CONCLUSION:The size and volume of muscles dominant eyes of AACE subjects change significantly to overcome binocular diplopia.The LR muscle become larger to compensate for the enhanced convergence in the AACE. 展开更多
关键词 acute acquired concomitant esotropia magnetic resonance imaging extraocular muscles
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Classic analogue of Autler–Townes-splitting transparency using a single magneto-optical ring resonator
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作者 吴利婷 曹文康 蒋昊林 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期420-427,共8页
We show that an optical transparency can be obtained by using only one single magneto-optical ring resonator. This effect is based on the splitting of counterclockwise and clockwise modes in the ring resonator. Within... We show that an optical transparency can be obtained by using only one single magneto-optical ring resonator. This effect is based on the splitting of counterclockwise and clockwise modes in the ring resonator. Within a proposed resonator-waveguide configuration the superposition between the two degeneracy broken modes produces a transparency window,which can be closed, open, and modified by tuning the applied magnetic field. This phenomenon is an analogue of Autler–Townes splitting, and the magnetic field is equivalent to the strong external pump field. We provide a theoretic analysis on the induced transparency, and numerically demonstrate the effect using full-wave simulation. Feasible implication of this effect and its potential applications are also discussed. 展开更多
关键词 magneto-optic effect dynamic tunable single optical ring resonator
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Topological resonators based on hexagonal-star valley photonic crystals
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作者 万鑫 彭晨阳 +2 位作者 李港 杨俊豪 齐新元 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期40-46,共7页
In valley photonic crystals, topological edge states can be gained by breaking the spatial inversion symmetry without breaking time-reversal symmetry or creating pseudo-spin structures, making highly unidirectional li... In valley photonic crystals, topological edge states can be gained by breaking the spatial inversion symmetry without breaking time-reversal symmetry or creating pseudo-spin structures, making highly unidirectional light transmission easy to achieve. This paper presents a novel physical model of a hexagonal-star valley photonic crystal. Simulations based on the finite element method(FEM) are performed to investigate the propagation of TM polarized mode and its application to ring resonators. The results show that such a topologically triangular ring resonator exhibits an optimum quality factor Q of about 1.25×104, and Q has a maximum value for both frequency and the cavity length L. Our findings are expected to have significant implications for developing topological lasers and wavelength division multiplexers. 展开更多
关键词 valley photonic crystals triangular resonant cavity topological edge state unidirectional transmis-sion
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Electro-mechanical coupling properties of band gaps in an with periodically attached “spring-mass” resonators
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作者 ZHANG Jian QIAN Deng-hui +1 位作者 REN Long WANG Qi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第3期429-443,共15页
The model of a locally resonant (LR) epoxy/PZT-4 phononic crystal (PC)nanobeam with “spring-mass” resonators periodically attached to epoxy is proposed. The corresponding band structures are calculated by coupling E... The model of a locally resonant (LR) epoxy/PZT-4 phononic crystal (PC)nanobeam with “spring-mass” resonators periodically attached to epoxy is proposed. The corresponding band structures are calculated by coupling Euler beam theory, nonlocal piezoelectricity theory and plane wave expansion (PWE) method. Three complete band gaps with the widest total width less than 10GHz can be formed in the proposed nanobeam by comprehensively comparing the band structures of three kinds of LR PC nanobeams with resonators attached or not. Furthermore, influencing rules of the coupling fields between electricity and mechanics,“spring-mass” resonator, nonlocal effect and different geometric parameters on the first three band gaps are discussed and summarized. All the investigations are expected to be applied to realize the active control of vibration in the region of ultrahigh frequency. 展开更多
关键词 phononic crystal nanobeam electro-mechanical coupling effect nonlocal effect locally resonant mechanism
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High-grade pancreatic intraepithelial neoplasia diagnosed based on changes in magnetic resonance cholangiopancreatography findings:A case report 被引量:2
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作者 Nao Furuya Atsushi Yamaguchi +13 位作者 Naohiro Kato Syuhei Sugata Takuro Hamada Takeshi Mizumoto Yuzuru Tamaru Ryusaku Kusunoki Toshio Kuwai Hirotaka Kouno Kazuya Kuraoka Yoshiyuki Shibata Sho Tazuma Takeshi Sudo Hiroshi Kohno Shiro Oka 《World Journal of Clinical Cases》 SCIE 2024年第8期1487-1496,共10页
BACKGROUND High-grade pancreatic intraepithelial neoplasia(PanIN)exhibits no mass and is not detected by any examination modalities.However,it can be diagnosed by pancreatic juice cytology from indirect findings.Most ... BACKGROUND High-grade pancreatic intraepithelial neoplasia(PanIN)exhibits no mass and is not detected by any examination modalities.However,it can be diagnosed by pancreatic juice cytology from indirect findings.Most previous cases were diagnosed based on findings of a focal stricture of the main pancreatic duct(MPD)and caudal MPD dilatation and subsequent pancreatic juice cytology using endoscopic retrograde cholangiopancreatography(ERCP).We experienced a case of high-grade PanIN with an unclear MPD over a 20-mm range,but without caudal MPD dilatation on magnetic resonance cholangiopancreatography(MRCP).CASE SUMMARY A 60-year-old female patient underwent computed tomography for a follow-up of uterine cancer post-excision,which revealed pancreatic cysts.MRCP revealed an unclear MPD of the pancreatic body at a 20-mm length without caudal MPD dilatation.Thus,course observation was performed.After 24 mo,MRCP revealed an increased caudal MPD caliber and a larger pancreatic cyst.We performed ERCP and detected atypical cells suspected of adenocarcinoma by serial pancreatic juice aspiration cytology examination.We performed a distal pancreatectomy and obtained a histopathological diagnosis of high-grade PanIN.Pancreatic parenchyma invasion was not observed,and curative resection was achieved.CONCLUSION High-grade Pan-IN may cause MPD narrowing in a long range without caudal MPD dilatation. 展开更多
关键词 Pancreatic cancer Pancreatic intraepithelial neoplasm High-grade pancreatic intraepithelial neoplasm Magnetic resonance cholangiopancreatography Carcinoma in situ Case report
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Resonantly enhanced second-and third-harmonic generation in dielectric nonlinear metasurfaces 被引量:1
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作者 Ji Tong Wang Pavel Tonkaev +5 位作者 Kirill Koshelev Fangxing Lai Sergey Kruk Qinghai Song Yuri Kivshar Nicolae C.Panoiu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第5期5-19,共15页
Nonlinear dielectric metasurfaces provide a promising approach to control and manipulate frequency conversion optical processes at the nanoscale,thus facilitating both advances in fundamental research and the developm... Nonlinear dielectric metasurfaces provide a promising approach to control and manipulate frequency conversion optical processes at the nanoscale,thus facilitating both advances in fundamental research and the development of new practical applications in photonics,lasing,and sensing.Here,we employ symmetry-broken metasurfaces made of centrosymmetric amorphous silicon for resonantly enhanced second-and third-order nonlinear optical response.Exploiting the rich physics of optical quasi-bound states in the continuum and guided mode resonances,we comprehensively study through rigorous numerical calculations the relative contribution of surface and bulk effects to second-harmonic generation(SHG)and the bulk contribution to third-harmonic generation(THG) from the meta-atoms.Next,we experimentally achieve optical resonances with high quality factors,which greatly boosts light-matter interaction,resulting in about 550 times SHG enhancement and nearly 5000-fold increase of THG.A good agreement between theoretical predictions and experimental measurements is observed.To gain deeper insights into the physics of the investigated nonlinear optical processes,we further numerically study the relation between nonlinear emission and the structural asymmetry of the metasurface and reveal that the generated harmonic signals arising from linear sharp resonances are highly dependent on the asymmetry of the meta-atoms.Our work suggests a fruitful strategy to enhance the harmonic generation and effectively control different orders of harmonics in all-dielectric metasurfaces,enabling the development of efficient active photonic nanodevices. 展开更多
关键词 second-harmonic generation third-harmonic generation bound state in the continuum guided mode resonance all-dielectric metasurfaces nonlinear optics
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