Physica Scripta最新文献_第10页

Novel method for inversion of microphysical properties of clouds using Raman lidar data 利用拉曼激光雷达数据反演云的微物理特性的新方法

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-10 DOI: 10.1088/1402-4896/ad75d4

Xinglin Yan, Liangliang Qi, Jiandong Mao, Juan Li and Hu Zhao

{"title":"Novel method for inversion of microphysical properties of clouds using Raman lidar data","authors":"Xinglin Yan, Liangliang Qi, Jiandong Mao, Juan Li and Hu Zhao","doi":"10.1088/1402-4896/ad75d4","DOIUrl":"https://doi.org/10.1088/1402-4896/ad75d4","url":null,"abstract":"Aerosol–cloud–precipitation interactions are important in the balance of Earth’s radiation budget. To further explore the relationship between clouds and precipitation, and to improve operational weather modification, it is necessary to study the microphysical parameters of liquid water clouds. Here, an inversion method that uses a back propagation (BP) neural network based on a genetic algorithm (GA), namely a GABP, is proposed to invert cloud microphysical parameters using ground-based dual-field-of-view (FOV) Raman lidar data. To verify the feasibility of the method, long-term continuous observations were conducted in the Liupan Mountains (China). Results revealed that the proposed inversion method using the GABP is feasible for retrieving the liquid water content (LWC) and the cloud droplet effective radius after training a large number of data measured simultaneously by the Raman lidar and a microwave radiometer. When inverting LWC, the root mean square error (RMSE) of the GABP algorithm was found in the range 0–0.005, whereas the RMSE of the BP algorithm fluctuated in the range 0–0.01. It was evident that the GABP algorithm yields better inversion results and finer detail. When maintaining other variables and comparing the inversion results of signals in the inner and outer FOVs, the RMSE of the inner FOV signal was within 0.005 at near-ground heights (i.e., <2 km), whereas the outer FOV signal exceeded 0.005 at certain heights. This study developed a feasible solution for detecting characteristic cloud microphysical parameters using a Raman lidar, which could be used to study aerosol–cloud–precipitation interactions, and thereby have considerable practical importance for improving artificial rainfall operations.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

High-Q resonances based on BIC in graphene-dielectric hybrid double-T metasurfaces for terahertz modulation and sensing 基于石墨烯-电介质混合双 T 元表面中 BIC 的高 Q 值共振，用于太赫兹调制和传感

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-09 DOI: 10.1088/1402-4896/ad74b2

Yaqi Wang, Yunping Qi, Zihao Zhou, Zhexian Li and Xiangxian Wang

{"title":"High-Q resonances based on BIC in graphene-dielectric hybrid double-T metasurfaces for terahertz modulation and sensing","authors":"Yaqi Wang, Yunping Qi, Zihao Zhou, Zhexian Li and Xiangxian Wang","doi":"10.1088/1402-4896/ad74b2","DOIUrl":"https://doi.org/10.1088/1402-4896/ad74b2","url":null,"abstract":"In recent years, there has been a growing interest in bound states in the continuum (BIC) in metasurfaces. One particular area of focus is achieving high-quality (Q) factor resonance, as this is crucial for enhancing the performance of refractive index sensors. In this study, a graphene-dielectric hybrid metasurface that supports the bound states in the continuum is proposed. By varying the width of the dielectric rectangle, quasi-BIC resonances with a high Q factor can be excited, and the Q factor can reach 752724.95 and 272004.759 respectively. The analysis of multipole decomposition reveals that the two quasi-BIC resonances are predominantly influenced by the electric quadrupole and magnetic dipole, respectively. Moreover, the transmittance of the resonance point can be changed rapidly with the change of the chemical potential of graphene, so the function of modulation can be realized by changing the chemical potential of graphene. Based on these findings, we have designed a terahertz wave modulator, which exhibits modulation depths of 98.1% and 99.9% at the two resonance peaks, respectively. The corresponding chemical potential shifts are 50 meV and 0.5 eV. Additionally, we have investigated the sensing performance of the metasurface. By analyzing the magnitude of the frequency shifts of the quasi-BIC resonance peaks at different gas refractive indexes, we have determined sensitivities of 740 GHz RIU−1 and 630 GHz RIU−1 at the two resonance peaks. The maximum figure of merit (FOM) values are 132911.39 RIU−1 and 45000 RIU−1, respectively. This research serves as a valuable reference for the design of dynamic optical modulators and sensors operating in the terahertz band.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exceptional points and quantum phase transition in a fermionic extension of the Swanson oscillator 斯旺森振荡器费米子扩展中的异常点和量子相变

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-09 DOI: 10.1088/1402-4896/ad706b

Akash Sinha, Aritra Ghosh and Bijan Bagchi

引用次数: 0

SOS decomposition for general Bell inequalities in two qubits systems and its application to quantum randomness 双量子比特系统中一般贝尔不等式的 SOS 分解及其在量子随机性中的应用

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-09 DOI: 10.1088/1402-4896/ad7536

Wen-Na Zhao, Youwang Xiao, Ming Li, Li Xu and Shao-Ming Fei

{"title":"SOS decomposition for general Bell inequalities in two qubits systems and its application to quantum randomness","authors":"Wen-Na Zhao, Youwang Xiao, Ming Li, Li Xu and Shao-Ming Fei","doi":"10.1088/1402-4896/ad7536","DOIUrl":"https://doi.org/10.1088/1402-4896/ad7536","url":null,"abstract":"Bell non-locality is closely related with device independent quantum randomness. In this paper, we present a kind of sum-of-squares (SOS) decomposition for general Bell inequalities in two qubits systems. By using the obtained SOS decomposition, we can then find the measurement operators associated with the maximal violation of considered Bell inequality. We also practice the SOS decomposition method by considering the (generalized) Clauser-Horne-Shimony-Holt (CHSH) Bell inequality, the Elegant Bell inequality, the Gisin inequality and the Chained Bell inequality as examples. The corresponding SOS decompositions and the measurement operators that cause the maximum violation values of these Bell inequalities are derived, which are consistent with previous results. We further discuss the device independent quantum randomness by using the SOS decompositions of Bell inequalities. We take the generalized CHSH inequality with the maximally entangled state and the Werner state that attaining the maximal violations as examples. Exact value or lower bound on the maximal guessing probability using the SOS decomposition are obtained. For Werner state, the lower bound can supply a much precise estimation of quantum randomness when p tends to 1.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Non-Hermitian quantum walks and non-Markovianity: the coin-position interaction 非ermitian量子行走与非马尔可夫性：硬币位置的相互作用

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-09 DOI: 10.1088/1402-4896/ad753f

Himanshu Badhani, Subhashish Banerjee and C M Chandrashekar

{"title":"Non-Hermitian quantum walks and non-Markovianity: the coin-position interaction","authors":"Himanshu Badhani, Subhashish Banerjee and C M Chandrashekar","doi":"10.1088/1402-4896/ad753f","DOIUrl":"https://doi.org/10.1088/1402-4896/ad753f","url":null,"abstract":"A -symmetric, non-Hermitian Hamiltonian in the -unbroken regime can lead to unitary dynamics under the appropriate choice of the Hilbert space. The Hilbert space is determined by a Hamiltonian-compatible inner product map on the underlying vector space, facilitated by a ‘metric operator’. A more traditional method, however, involves treating the evolution as open system dynamics, and the state is constructed through normalization at each time step. In this work, we present a comparative study of the two methods of constructing the reduced dynamics of a system evolving under a -symmetric Hamiltonian. Our system is a one-dimensional quantum walk with the spin and position degrees of freedom forming its two subsystems. We compare the information flow between the subsystems under the two methods. We find that under the metric formalism, a power law decay of the information backflow to the subsystem gives a clear indication of the transition from -unbroken to the broken phase. This is unlike the information backflow under the normalized state method. We also note that even though non-Hermiticity models open system dynamics, pseudo-Hermiticity can increase entanglement between the subsystem in the metric Hilbert space, thus indicating that pseudo-Hermiticity cases can be seen as a resource in quantum mechanics.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A wide angle beam scanning CRLH leaky-wave antenna with non-identical elements per unit-cells 每单元非相同元件的广角波束扫描 CRLH 漏波天线

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-09 DOI: 10.1088/1402-4896/ad693c

H Zamini, M Afsahi, H R Dalili Oskouei and M Mohammadi Shirkolaei

{"title":"A wide angle beam scanning CRLH leaky-wave antenna with non-identical elements per unit-cells","authors":"H Zamini, M Afsahi, H R Dalili Oskouei and M Mohammadi Shirkolaei","doi":"10.1088/1402-4896/ad693c","DOIUrl":"https://doi.org/10.1088/1402-4896/ad693c","url":null,"abstract":"In this research article, a wide-angle scanning leaky-wave antenna (LWA) based on the composite right/left-handed (CRLH) metamaterial (MTM) operating over the C-band spectrum for mobile applications is proposed, investigated, and realized. The proposed LWA includes nine CRLH-MTM-based unit-cells. The properties of CRLH-MTM have been applied using series slots and shunt metallic via-holes. Each unit cell consists of three patches, two external patches, and one smaller middle patch implemented between them. One slot has been etched on each external patch; the width of these two slots is unequal. Moreover, the distance of the middle patch with each side patch is different. The results show that using this method of realizing non-identical elements caused the achievement of proper return-loss at the transition frequency and provided the balanced CRLH metamaterial condition. Additionally, using CRLH-MTM properties by realizing series capacitance (slot) and shunt inductance (via-holes) made the wide-angle scant from backward to forward radiation pattern. The results demonstrate that the LW antenna with small dimensions of 251.5 × 30 × 1.575 mm3 operates over a frequency range of 4.8–6.13 GHz covering a wide beam scanning range from to with broadside radiation at the center frequency of 5.46 GHz. The radiation gain of the proposed antenna varies from 6.2–13.1 dB. The achievements confirm the effectiveness of the proposed methods to realize a high-performance LW-antenna with the advantages of simple design, low profile, low cost, and easy of manufacture for mobile applications.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The mechanism of adjusting the low-frequency ultra-wide band gap within lightweight spherical superstructue 轻质球形上层结构内部低频超宽带隙的调节机制

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-09 DOI: 10.1088/1402-4896/ad74a3

Yongyan Zhang, Zebo Zhao, Xiangjie Miao, Jiuhui Wu, Liming Chen, Biao Li, Hui Liu, Leipeng Yang, Qinglong Liu, Tao Chen and Suobin Li

{"title":"The mechanism of adjusting the low-frequency ultra-wide band gap within lightweight spherical superstructue","authors":"Yongyan Zhang, Zebo Zhao, Xiangjie Miao, Jiuhui Wu, Liming Chen, Biao Li, Hui Liu, Leipeng Yang, Qinglong Liu, Tao Chen and Suobin Li","doi":"10.1088/1402-4896/ad74a3","DOIUrl":"https://doi.org/10.1088/1402-4896/ad74a3","url":null,"abstract":"Conventional resonant structures can be effective in obtaining broadband, but it is still a challenge to design small-sized and lightweight acoustic metamaterials with a low-frequency ultra-wideband. This paper proposes a new approach of designing a lightweight spherical localized resonance superstructure with adjustable stiffness ratio, and the mechanism of adjusting the low-frequency ultra-wide forbidden band is revealed. Then, the correlation between the zero value of its dynamic equivalent mass and the stiffness ratio of the system is studied. It is found that not only is the upper bound of the negative mass effectively broadened, but also the lower bound is successfully lowered only by adjusting the stiffness ratio of the sphere. Most importantly, based on the regulation mechanism with adjustable stiffness ratio, the lower boundary of the band gap is lowered from 171 Hz to 141 Hz, and the upper boundary is increased from 445 Hz to 710 Hz. Therefore, the low-frequency ultra-wideband of 141–710 Hz is obtained only by adjusting the stiffness ratio of the system and the Finite Element Method, which is highly consistent with theoretical analyses. Obviously, the mechanism of obtaining the low-frequency wideband through adjusting the stiffness ratio not only provides a novel idea for adjusting the low-frequency ultra-wideband, but also provides theoretical guidance for the developing the small-size and lightweight acoustic devices, so it would have potential application in the field of vibration and noise reduction.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A capillary fiber-based liquid metal pressure sensor 基于毛细纤维的液态金属压力传感器

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-09 DOI: 10.1088/1402-4896/ad74b0

Xiao-Ping Zhou and Qi Zhang

{"title":"A capillary fiber-based liquid metal pressure sensor","authors":"Xiao-Ping Zhou and Qi Zhang","doi":"10.1088/1402-4896/ad74b0","DOIUrl":"https://doi.org/10.1088/1402-4896/ad74b0","url":null,"abstract":"The capillary fibers can easily be prefabricated in the factory, and their production cost is reduced. Moreover, the liquid metal fibers have the advantages of good integrity, excellent electrical conductivity, inherent stretchability, easy phase transition, and can be woven or knitted into smart fabrics. To solve the problems of the complex manufacture process and low integrity of lithographic sensors, capillary fibers replace the lithographic microfluidic channel to fill liquid metal to manufacture the pressure sensor in this paper. The prefabricated fiber is poured directly to produce the flexible chip. The steel shell is employed to increase the sensor’s measuring range and to enhance its overall performance. Compression experiments on the developed sensor are conducted, and pressure-resistance curves of the developed pressure sensor are obtained. The analytical solution of the pressure for the developed sensor is derived, and the analytical results are in good agreement with the experimental data. The cyclic loading experimental result shows that the measuring range of the chip is from 0 kPa to 1900 kPa with a full-scale output value of 1644 mΩ, linearity varying from 0.14 to 1.22 mΩ kPa−1, curve coincidence of 48.2%, repeatability of 2.77% and hysteresis of 5.26%. The measuring range of the developed pressure sensor is from 0 MPa to 20 MPa with a full-scale output value of 1046 mΩ, linearity ranging from 35.63 to 70.20 mΩ MPa−1, curve coincidence of 7.5%, repeatability of 2.35% and hysteresis of 4.53%. The comparison of performance indexes shows that the capillary fiber-based chip has good measurement performance, and the introduction of steel shell further improves the measurement performance.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multicast-based fault-tolerant multiparty state preparation of four-qubit cluster states 基于组播的四量子比特群状态容错多方准备

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-09 DOI: 10.1088/1402-4896/ad753c

TianTian Meng, YuZhen Wei, Min Jiang, Hong Chen and Xu Huang

引用次数: 0

Innovative lightweight deep learning architecture for enhanced rice pest identification 用于增强水稻害虫识别的创新型轻量级深度学习架构

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-08-11 DOI: 10.1088/1402-4896/ad69d5

Haiying Song, Yiying Yan, Shijun Deng, Cen Jian and Jianbin Xiong

{"title":"Innovative lightweight deep learning architecture for enhanced rice pest identification","authors":"Haiying Song, Yiying Yan, Shijun Deng, Cen Jian and Jianbin Xiong","doi":"10.1088/1402-4896/ad69d5","DOIUrl":"https://doi.org/10.1088/1402-4896/ad69d5","url":null,"abstract":"Pest detection is a crucial aspect of rice production. Accurate and timely identification of rice pests can assist farmers in taking prompt measures for control. To enhance the precision and real-time performance of rice pest detection, this paper introduces a novel YOLOv8-SCS architecture that integrates Space-to-Depth Convolution (SPD-Conv), Context Guided block (CG block), and Slide Loss. Initially, the original algorithm’s convolutional module is improved by introducing the SPD-Conv module, which reorganises the input channel dimensions into spatial dimensions, enabling the model to capture fine-grained pest features more efficiently while maintaining a lightweight model architecture. Subsequently, the CG block module is integrated into the CSPDarknet53 to 2-Stage FPN (C2f) structure, maintaining the models lightweight nature while enhancing its feature extraction capabilities. Finally, the Binary Cross-Entropy (BCE) is refined by incorporating the Slide Loss function, which encourages the model to focus more on challenging samples during training, thereby improving the model’s generalization across various samples. To validate the effectiveness of the improved algorithm, a series of experiments were conducted on a rice pest dataset. The results demonstrate that the proposed model outperforms the original YOLOv8 in rice pest detection, achieving an mAP of 87.9%, which is a 5.7% improvement over the original YOLOv8. The model also features a 44.1% reduction in parameter count and a decrease of 11.7 GFLOPs in computational requirements, meeting the demands for real-time detection.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":null,"pages":null},"PeriodicalIF":2.9,"publicationDate":"2024-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141969338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0