Zhan Su, HaiQi Xi, Yan Gao, Lin Zhang, Ben Yang, Zhifeng Zhang
The existing fire alarm system has strict distance and installation requirements between the fire point and the detector, and is easy to be interfered by environmental factors. It is not suitable for places with large space and many interference factors such as Climbazole production line. This paper proposed a flame image detection technology based on RGB+HSI color model and the detection system is designed and developed. The experimental results show that the flame image detection system based on RGB+HSI color model has the better recognition efficiency, which meets the real-time and accuracy requirements for early flame image detection in Climbazole production line.
{"title":"Research on flame image processing of climbazole production line based on RGB+HSI color model","authors":"Zhan Su, HaiQi Xi, Yan Gao, Lin Zhang, Ben Yang, Zhifeng Zhang","doi":"10.1117/12.2683898","DOIUrl":"https://doi.org/10.1117/12.2683898","url":null,"abstract":"The existing fire alarm system has strict distance and installation requirements between the fire point and the detector, and is easy to be interfered by environmental factors. It is not suitable for places with large space and many interference factors such as Climbazole production line. This paper proposed a flame image detection technology based on RGB+HSI color model and the detection system is designed and developed. The experimental results show that the flame image detection system based on RGB+HSI color model has the better recognition efficiency, which meets the real-time and accuracy requirements for early flame image detection in Climbazole production line.","PeriodicalId":184319,"journal":{"name":"Optical Frontiers","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125871319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Haoxuan Xun, Benard K. Chen, Yusheng Zhou, A. Yang, J. Shao, Yaohui Zhan, Xiaofeng Li
Thermal emitter, as one of the important components in the thermal photovoltaic system, is mainly used to absorb the energy radiated by the heat source and convert it into energy that can be absorbed by the photovoltaic cell. We use the RCWA algorithm to optimize the thermal emitter based on the refractory metal Mo microhole array with a quadrangular arrangement. The optimized structure has a high selective emissivity characteristic in the 1-2.4 μm waveband. The averaged emissivity can reach more than 79.6%, which is about 60% higher than that of the unstructured emitter; at the same time, the band emissivity gradually decreases after the wavelength of 2.4 μm, achieving a selective emission control. Using the laser direct writing technology, dry metal etching, and other micro-fabrication techniques, the thermal emitter is fabricated with the feature sizes as follows: the hole diameter, the array period, and the hole depth are 1 μm, 1.4 μm, and 3.4 μm, respectively; the area with microhole structures is 12×12 mm. The experimental measurement suggests that the averaged emissivity arrives at 70.07%. This study provides an alternative candidate for selective thermal emitters and also offers a technical experience for practical applications.
{"title":"Study on thermal emission regulation based on refractory metal Mo microstructures","authors":"Haoxuan Xun, Benard K. Chen, Yusheng Zhou, A. Yang, J. Shao, Yaohui Zhan, Xiaofeng Li","doi":"10.1117/12.2683100","DOIUrl":"https://doi.org/10.1117/12.2683100","url":null,"abstract":"Thermal emitter, as one of the important components in the thermal photovoltaic system, is mainly used to absorb the energy radiated by the heat source and convert it into energy that can be absorbed by the photovoltaic cell. We use the RCWA algorithm to optimize the thermal emitter based on the refractory metal Mo microhole array with a quadrangular arrangement. The optimized structure has a high selective emissivity characteristic in the 1-2.4 μm waveband. The averaged emissivity can reach more than 79.6%, which is about 60% higher than that of the unstructured emitter; at the same time, the band emissivity gradually decreases after the wavelength of 2.4 μm, achieving a selective emission control. Using the laser direct writing technology, dry metal etching, and other micro-fabrication techniques, the thermal emitter is fabricated with the feature sizes as follows: the hole diameter, the array period, and the hole depth are 1 μm, 1.4 μm, and 3.4 μm, respectively; the area with microhole structures is 12×12 mm. The experimental measurement suggests that the averaged emissivity arrives at 70.07%. This study provides an alternative candidate for selective thermal emitters and also offers a technical experience for practical applications.","PeriodicalId":184319,"journal":{"name":"Optical Frontiers","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122223479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xinyi Liu, P. Jiang, Jialu Wang, Qiang Xu, Tingting Yang, Xinyi Fan
In this paper, we presented the inscription and sensing characteristics of eccentric fiber Bragg gratings (EFBGs) through femtosecond laser. This kind of fiber grating is caused by localized refractive index modulation that deviates from the center of the fiber core. EFBGs were prepared in SMF-28 single-mode fiber by 800nm femtosecond laser point-by-point writing method. The temperature and refractive index sensing properties of the prepared EFBG were investigated. The experimental results show that both the Bragg wavelength and cladding mode resonance wavelength of EFBG increase linearly with temperature and show extremely high-temperature robustness. The temperature sensitivity of Bragg resonance is 14.4 pm/℃. As the SRI increases, the Bragg peak remains unchanged and the cutoff wavelength of EFBG cladding mode resonance red-shifts with a sensitivity of 649.29 nm/RIU.
{"title":"Femtosecond laser pulses inscribed EFBG and its sensing characteristics","authors":"Xinyi Liu, P. Jiang, Jialu Wang, Qiang Xu, Tingting Yang, Xinyi Fan","doi":"10.1117/12.2684657","DOIUrl":"https://doi.org/10.1117/12.2684657","url":null,"abstract":"In this paper, we presented the inscription and sensing characteristics of eccentric fiber Bragg gratings (EFBGs) through femtosecond laser. This kind of fiber grating is caused by localized refractive index modulation that deviates from the center of the fiber core. EFBGs were prepared in SMF-28 single-mode fiber by 800nm femtosecond laser point-by-point writing method. The temperature and refractive index sensing properties of the prepared EFBG were investigated. The experimental results show that both the Bragg wavelength and cladding mode resonance wavelength of EFBG increase linearly with temperature and show extremely high-temperature robustness. The temperature sensitivity of Bragg resonance is 14.4 pm/℃. As the SRI increases, the Bragg peak remains unchanged and the cutoff wavelength of EFBG cladding mode resonance red-shifts with a sensitivity of 649.29 nm/RIU.","PeriodicalId":184319,"journal":{"name":"Optical Frontiers","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128345830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An experimental scheme based on interferometry is designed to measure the orbital angular momentum spectrum of vortex beam perturbed by turbulence. The orbital angular momentum spectrum of vortex beam can be calculated by using four light intensity images. The laser beam is modulated by a spatial light modulator to obtain a vortex beam, and then passes through another spatial light modulator loaded with a turbulent phase perturbation hologram to interfere with the reference beam. The orbital angular momentum spectrum of the vortex beam can be obtained by making use of two interference patterns and the intensity patterns of the vortex beam and the reference beam. The results show that the experimental scheme can measure the orbital angular momentum spectrum of the vortex beam affected by turbulence.
{"title":"Measuring the orbital angular momentum spectrum of vortex beam disturbed by turbulence","authors":"Chao Huang, Lu Bai, Yankun Wang, J. Bai","doi":"10.1117/12.2684962","DOIUrl":"https://doi.org/10.1117/12.2684962","url":null,"abstract":"An experimental scheme based on interferometry is designed to measure the orbital angular momentum spectrum of vortex beam perturbed by turbulence. The orbital angular momentum spectrum of vortex beam can be calculated by using four light intensity images. The laser beam is modulated by a spatial light modulator to obtain a vortex beam, and then passes through another spatial light modulator loaded with a turbulent phase perturbation hologram to interfere with the reference beam. The orbital angular momentum spectrum of the vortex beam can be obtained by making use of two interference patterns and the intensity patterns of the vortex beam and the reference beam. The results show that the experimental scheme can measure the orbital angular momentum spectrum of the vortex beam affected by turbulence.","PeriodicalId":184319,"journal":{"name":"Optical Frontiers","volume":"49 13","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120888997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Photoelectrochemical (PEC) sensors have the advantages of high sensitivity, low background noise, and fast response time, and are suitable for environmental monitoring, biomedical, and chemical industries. In this work, a photocathode whose photoresponses weaken with increasing concentration of the substance is proposed and used for Cr(VI) sensing, and a wide concentration range (0.04−16 µM) for Cr(VI) can be detected by just using one NiO film, with a sensing sensitivity of 0.69 lgC µAµM-1 cm-2 (where C is the concentration) and a low detection limit of 0.01 µM. The successful detection of Cr(VI) was achieved through the signal-weakening photoelectrochemical responses, as evidenced by the decrease in the photocathode signal with increasing Cr(VI) concentration. This can be attributed to the steric hindrance effect caused by the in-situ formation of Cr(OH)3 precipitates. Our proposed scheme can be successfully used for the monitoring of Cr(VI) in drinking water, as the world health organization requirement of 0.96 µM is included in the linear detection range.
{"title":"A NiO film photocathode with a signal-weakening photoresponse for hexavalent chromium detection","authors":"Wenxiang Lu, Lu Ma, Shengchen Ke, Rouxi Zhang, Weijian Zhu, Linling Qin, Shaolong Wu","doi":"10.1117/12.2684053","DOIUrl":"https://doi.org/10.1117/12.2684053","url":null,"abstract":"Photoelectrochemical (PEC) sensors have the advantages of high sensitivity, low background noise, and fast response time, and are suitable for environmental monitoring, biomedical, and chemical industries. In this work, a photocathode whose photoresponses weaken with increasing concentration of the substance is proposed and used for Cr(VI) sensing, and a wide concentration range (0.04−16 µM) for Cr(VI) can be detected by just using one NiO film, with a sensing sensitivity of 0.69 lgC µAµM-1 cm-2 (where C is the concentration) and a low detection limit of 0.01 µM. The successful detection of Cr(VI) was achieved through the signal-weakening photoelectrochemical responses, as evidenced by the decrease in the photocathode signal with increasing Cr(VI) concentration. This can be attributed to the steric hindrance effect caused by the in-situ formation of Cr(OH)3 precipitates. Our proposed scheme can be successfully used for the monitoring of Cr(VI) in drinking water, as the world health organization requirement of 0.96 µM is included in the linear detection range.","PeriodicalId":184319,"journal":{"name":"Optical Frontiers","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125727185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In hazy scenarios, suspended particles in the atmosphere will absorb and scatter the transmitted natural light, resulting in a serious degradation of image quality obtained by imaging equipment, which greatly affects the visual perception of images. Aiming at the problems such as low contrast, color distortion and lack of detail information in areas with high haze concentration in images acquired by image acquisition equipment in hazy days, this paper proposes a dehazing algorithm based on exposure image fusion based on multi-logarithmic transform, which improves image quality while effectively dehazing images and avoids the edge effect in the sky part of images after dehazing. Firstly, the original hazy image was transformed by logarithmic multiple times to produce multiple images with different exposure to be fused. Then, all the input images with logarithmic transformation and weight graphs were fused by multi-scale pyramid fusion method to obtain the dehazing image. In order to verify the effectiveness of the algorithm in this paper, the results of the proposed algorithm and six mainstream image dehazing algorithms are compared in two aspects: subjective evaluation and objective evaluation. Experimental results show that the image processed by the proposed algorithm presents better visual effects than that processed by other algorithms. The proposed algorithm can effectively improve image contrast, improve image distortion, improve the visibility of detail information in areas with high hazy concentration, and the scenery color is natural. Good results are obtained under two objective evaluation indexes of image quality, namely peak signal-to-noise ratio and structural similarity, which further proves that the algorithm proposed in this paper has good dehazing performance, can effectively improve the image visibility, and has a good overall color preservation degree of the image.
{"title":"Image fusion dehazing algorithm based on multi-logarithmic transform","authors":"Xiaoping Zhou","doi":"10.1117/12.2683823","DOIUrl":"https://doi.org/10.1117/12.2683823","url":null,"abstract":"In hazy scenarios, suspended particles in the atmosphere will absorb and scatter the transmitted natural light, resulting in a serious degradation of image quality obtained by imaging equipment, which greatly affects the visual perception of images. Aiming at the problems such as low contrast, color distortion and lack of detail information in areas with high haze concentration in images acquired by image acquisition equipment in hazy days, this paper proposes a dehazing algorithm based on exposure image fusion based on multi-logarithmic transform, which improves image quality while effectively dehazing images and avoids the edge effect in the sky part of images after dehazing. Firstly, the original hazy image was transformed by logarithmic multiple times to produce multiple images with different exposure to be fused. Then, all the input images with logarithmic transformation and weight graphs were fused by multi-scale pyramid fusion method to obtain the dehazing image. In order to verify the effectiveness of the algorithm in this paper, the results of the proposed algorithm and six mainstream image dehazing algorithms are compared in two aspects: subjective evaluation and objective evaluation. Experimental results show that the image processed by the proposed algorithm presents better visual effects than that processed by other algorithms. The proposed algorithm can effectively improve image contrast, improve image distortion, improve the visibility of detail information in areas with high hazy concentration, and the scenery color is natural. Good results are obtained under two objective evaluation indexes of image quality, namely peak signal-to-noise ratio and structural similarity, which further proves that the algorithm proposed in this paper has good dehazing performance, can effectively improve the image visibility, and has a good overall color preservation degree of the image.","PeriodicalId":184319,"journal":{"name":"Optical Frontiers","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115567529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Q. Fu, K. Lou, Jing Qian, Guande Wang, Quanzhong Zhao
Dual-scale structures with chemical modification were fabricated on the titanium surfaces by a combination of a picosecond (ps) laser parallelly direct writing microstructures, a femtosecond (fs) laser inducing nanoripples and a chemical solution modification. Two kinds of microstructures (microholes and mircopillars) were created at different intervals for comparison, and nanoripples were induced dividually, which provided possibility to evaluate the roles of structures and chemistry. After each step, the samples were cleaned in ultrasonic cleaning machine and stored in seal bags to suppress interferences. The results showed that low surface energy is necessary for hydrophobic on titanium surface, and mircopillar had a greater capacity of wetting regulation. In additions, a “structures saturation effect” was also found, which were disagree with the Wenzel model.
{"title":"Anomalous wetting behaviors of hierarchical micro-nanostructures parallelly fabricated by ultrafast laser pulses on titanium","authors":"Q. Fu, K. Lou, Jing Qian, Guande Wang, Quanzhong Zhao","doi":"10.1117/12.2683536","DOIUrl":"https://doi.org/10.1117/12.2683536","url":null,"abstract":"Dual-scale structures with chemical modification were fabricated on the titanium surfaces by a combination of a picosecond (ps) laser parallelly direct writing microstructures, a femtosecond (fs) laser inducing nanoripples and a chemical solution modification. Two kinds of microstructures (microholes and mircopillars) were created at different intervals for comparison, and nanoripples were induced dividually, which provided possibility to evaluate the roles of structures and chemistry. After each step, the samples were cleaned in ultrasonic cleaning machine and stored in seal bags to suppress interferences. The results showed that low surface energy is necessary for hydrophobic on titanium surface, and mircopillar had a greater capacity of wetting regulation. In additions, a “structures saturation effect” was also found, which were disagree with the Wenzel model.","PeriodicalId":184319,"journal":{"name":"Optical Frontiers","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114322064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The 1319 nm laser is widely used in sodium beacon, optical communication and laser medical fields, and also a potential pump source for 4.3 μm output. In this work, we reported a laser diode partially end-pumped Nd:YAG slab laser operation at 1319 nm. A stable plano-concave cavity was adopted. The maximum continuous output power of 24.33 W was obtained for the absorbed pump power of 222 W, exhibiting an optical conversion efficiency of 10.96% and a slope efficiency of 23.06%. The beam quality was measured to be M2 = 1.19 in the vertical direction.
{"title":"Partially end-pumped 1319 nm Nd:YAG slab laser","authors":"Shengzi Zhang, Tanghan Chen, Xiaomeng Liu, Heng-li Zhang, Jiang-Shan Wang, Heqing Guo","doi":"10.1117/12.2684961","DOIUrl":"https://doi.org/10.1117/12.2684961","url":null,"abstract":"The 1319 nm laser is widely used in sodium beacon, optical communication and laser medical fields, and also a potential pump source for 4.3 μm output. In this work, we reported a laser diode partially end-pumped Nd:YAG slab laser operation at 1319 nm. A stable plano-concave cavity was adopted. The maximum continuous output power of 24.33 W was obtained for the absorbed pump power of 222 W, exhibiting an optical conversion efficiency of 10.96% and a slope efficiency of 23.06%. The beam quality was measured to be M2 = 1.19 in the vertical direction.","PeriodicalId":184319,"journal":{"name":"Optical Frontiers","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117285251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Constructing novel hybrid nanostructure has become an effective strategy to enhance the performance of photoelectrochemical (PEC) biosensors. However, most of the H2O2-sensing photoelectrodes require enzyme modification, which limits the working environment and sensing performance. Herein, the burr-like CuO nanostructures are modified on the entire surfaces of the ordered Si nanowires (SiNWs) by using a combination of magnetron sputtering and hydrothermal growth. The optimized CuO@SiNWs heterojunction with a core-shell structure enables enzyme-free PEC detection of H2O2, achieving a sensitivity of 227.76 μAmM-1cm-2 in the concentration range of 0–588 mM and a detection limit of 7.14 μM (Signal/Noise=3). The excellent sensing performance of the CuO@SiNWs is attributed to the large specific surface area provided by SiNWs and the CuO possess desired H2O2-catalytic activity while providing a great number of active sites. In addition, the CuO@SiNWs demonstrates satisfactory optical absorption. This work demonstrates that enzyme-free and highly sensitive H2O2 detection can be achieved by hybrid nanostructure, providing an alternative route to H2O2 sensing.
构建新型杂化纳米结构已成为提高光电化学(PEC)生物传感器性能的有效策略。然而,大多数h2o2传感光电极需要酶修饰,这限制了工作环境和传感性能。本文采用磁控溅射和水热生长相结合的方法在有序硅纳米线(SiNWs)的整个表面上修饰了毛刺状的CuO纳米结构。优化后的CuO@SiNWs异质结核壳结构实现了H2O2的无酶PEC检测,在0 ~ 588 mM的浓度范围内灵敏度为227.76 μ am -1cm-2,检出限为7.14 μM(信噪比=3)。CuO@SiNWs优异的传感性能归功于SiNWs提供的大比表面积和CuO在提供大量活性位点的同时具有理想的h2o2催化活性。此外,CuO@SiNWs具有良好的光吸收性能。这项工作表明,通过混合纳米结构可以实现无酶和高灵敏度的H2O2检测,为H2O2传感提供了另一种途径。
{"title":"CuO modified Si nanowires for enzyme-free photoelectrochemical sensing of H2O2","authors":"Ruoxi Zhang, Shengchen Ke, Wenxiang Lu, Weijian Zhu, Lu Ma, Linling Qin, Shaolong Wu","doi":"10.1117/12.2683954","DOIUrl":"https://doi.org/10.1117/12.2683954","url":null,"abstract":"Constructing novel hybrid nanostructure has become an effective strategy to enhance the performance of photoelectrochemical (PEC) biosensors. However, most of the H2O2-sensing photoelectrodes require enzyme modification, which limits the working environment and sensing performance. Herein, the burr-like CuO nanostructures are modified on the entire surfaces of the ordered Si nanowires (SiNWs) by using a combination of magnetron sputtering and hydrothermal growth. The optimized CuO@SiNWs heterojunction with a core-shell structure enables enzyme-free PEC detection of H2O2, achieving a sensitivity of 227.76 μAmM-1cm-2 in the concentration range of 0–588 mM and a detection limit of 7.14 μM (Signal/Noise=3). The excellent sensing performance of the CuO@SiNWs is attributed to the large specific surface area provided by SiNWs and the CuO possess desired H2O2-catalytic activity while providing a great number of active sites. In addition, the CuO@SiNWs demonstrates satisfactory optical absorption. This work demonstrates that enzyme-free and highly sensitive H2O2 detection can be achieved by hybrid nanostructure, providing an alternative route to H2O2 sensing.","PeriodicalId":184319,"journal":{"name":"Optical Frontiers","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126733241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Terahertz (THz) waves have great potential applications in communication, imaging, and spectroscopy fields. Effective THz modulators are highly desired to realize those functionalities. Wherein, as a kind of artificial composite material, THz metamaterials can achieve extraordinary responses to the electromagnetic wave through the geometric structure design. Nevertheless, normal metamaterials have no tunability once they have been designed and fabricated. To overcome this issue, active medias have been explored to enable the expected modulation of metamaterials under the external stimuli. Among them, phase transition materials are often used in dynamically tunable THz devices due to their intriguing properties. Particularly, vanadium dioxide (VO2) has attracted attention owing to the reversible physical properties and can exhibit insulator-to-metal transition (IMT) behavior at near room temperature. Here, we explore the strength of the resonance response and the change of spectral lineshape caused by the size variation in the metamaterial unit cell. On this basis, adding VO2 thin film can realize broadband modulation during the IMT process. Furthermore, by incorporating the VO2 patches in the gold microstructure can further achieve the dual modulation of amplitude and frequency simultaneously. The design of VO2 hybrid metamaterial can break the single function limitation of traditional metamaterial modulators, reduce material loss, and open up a new path for the development of multifunctional THz modulators.
{"title":"Dual-modulation terahertz device based on amplitude and frequency in VO2 hybrid metamaterial","authors":"Longyu Shi, Huiwen Shi, Xuteng Zhang, Wanlin Liang, Suqi Zhang, Huijuan Sun, Qing-li Zhou, Cunlin Zhang","doi":"10.1117/12.2683141","DOIUrl":"https://doi.org/10.1117/12.2683141","url":null,"abstract":"Terahertz (THz) waves have great potential applications in communication, imaging, and spectroscopy fields. Effective THz modulators are highly desired to realize those functionalities. Wherein, as a kind of artificial composite material, THz metamaterials can achieve extraordinary responses to the electromagnetic wave through the geometric structure design. Nevertheless, normal metamaterials have no tunability once they have been designed and fabricated. To overcome this issue, active medias have been explored to enable the expected modulation of metamaterials under the external stimuli. Among them, phase transition materials are often used in dynamically tunable THz devices due to their intriguing properties. Particularly, vanadium dioxide (VO2) has attracted attention owing to the reversible physical properties and can exhibit insulator-to-metal transition (IMT) behavior at near room temperature. Here, we explore the strength of the resonance response and the change of spectral lineshape caused by the size variation in the metamaterial unit cell. On this basis, adding VO2 thin film can realize broadband modulation during the IMT process. Furthermore, by incorporating the VO2 patches in the gold microstructure can further achieve the dual modulation of amplitude and frequency simultaneously. The design of VO2 hybrid metamaterial can break the single function limitation of traditional metamaterial modulators, reduce material loss, and open up a new path for the development of multifunctional THz modulators.","PeriodicalId":184319,"journal":{"name":"Optical Frontiers","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121073946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}