Pub Date : 2025-02-01DOI: 10.1016/j.ijleo.2024.172169
Rui Wang , Jingwen Sun , Chunhua Xue , Teng Li
Based on the concept of Risley prism and phase gradient lens theory for beam steerability, an innovative architecture for reducing the phase coverage of a phase gradient transmitarray is proposed by using axially rotating beam steering antenna. By employing the proposed folded antenna system, the profile height is reduced by half and the implementation of transmitarray is simplified with only phase coverage for supercells due to the twice transmission. A concise linear-polarized prototype is designed and experimented for validation. The measured results demonstrate that the system can realize the beam-steering within a conical solid angle ranging , with a peak gain of 24.8 dBi at the beam direction at 30 GHz. The proposed axial-rotation folded reflective-transmissive hybrid array provides a new approach for beam steering which is a good candidate for communication systems.
{"title":"Axial-rotation beam-steering folded reflective-transmissive hybrid array","authors":"Rui Wang , Jingwen Sun , Chunhua Xue , Teng Li","doi":"10.1016/j.ijleo.2024.172169","DOIUrl":"10.1016/j.ijleo.2024.172169","url":null,"abstract":"<div><div>Based on the concept of Risley prism and phase gradient lens theory for beam steerability, an innovative architecture for reducing the phase coverage of a phase gradient transmitarray is proposed by using axially rotating beam steering antenna. By employing the proposed folded antenna system, the profile height is reduced by half and the implementation of transmitarray is simplified with only <span><math><mrow><mn>180</mn><mo>°</mo></mrow></math></span> phase coverage for supercells due to the twice transmission. A concise linear-polarized prototype is designed and experimented for validation. The measured results demonstrate that the system can realize the beam-steering within a conical solid angle ranging <span><math><mrow><mo>±</mo><mn>49</mn><mo>°</mo></mrow></math></span>, with a peak gain of 24.8 dBi at the <span><math><mrow><mn>0</mn><mo>°</mo></mrow></math></span> beam direction at 30 GHz. The proposed axial-rotation folded reflective-transmissive hybrid array provides a new approach for beam steering which is a good candidate for communication systems.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"321 ","pages":"Article 172169"},"PeriodicalIF":3.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143183066","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ijleo.2024.172188
Yusuf Shehu , Alghareeb Abbas A. M , Naser M. Ahmed , Sameen Aslam , Siti Azrah Mohamad Samsuri , W. M. Edmund Loh
The excellent photoelectric properties, high stability, and low-cost fabrication have gained TiO2 tremendous attention as a cutting-edge material for various energy-related applications. However, the bandgap energy in the UV range and the low excited states of TiO2 have urged researchers to incorporate different dopant elements to optimize its properties. We demonstrated the effect of antimony (Sb) incorporation to TiO2 as UV photodetector using chemical bath deposition technique. The structural, optical, and electrical behaviour of undoped and doped devices (Sb:TiO2) were analyzed. Under UV irradiation at a wavelength of 365 nm and a power intensity of 130 μW, we achieved remarkable enhancement in device sensitivity. Compared to an undoped device (TiO2-Ns/PSi/Ag), the doped device (Sb:TiO2-Ns/PSi/Ag) demonstrated superior photoresponse and performance. The device exhibited Schottky characteristics within a voltage range of -5V to 5 V, demonstrating strong responsiveness and excellent electrical behaviour. I-V analysis at bias voltages of 3 V, and 5 V revealed outstanding responsivity and sensitivity. The best optimized performance device (Sb:TiO2-Ns/PSi/Ag) demonstrate highest photodetector parameters of responsivity as 23.5 A/W, quantum efficiency as ∼8 × 103%, sensitivity as 685.71 %, gain as 7.86, detectivity as 1.97 × 1012 Jones, and NEP as 9.0 × 10–14 W compared to that of the undoped TiO2 device (TiO2-Ns/PSi/Ag) with responsivity of 15.4 A/W, quantum efficiency as 5.22 × 103%, sensitivity as 420.81 %, gain as 5.21 detectivity as 1.25 × 1012 Jones, and NEP as 1.42 × 10–13 W, as a results of Sb incorporation to TiO2 both under UV light illumination (wavelength 365 nm and power intensity of 130 μW) at 5 V bias voltage. These findings underscore the significant impact of Sb doping on TiO2 for photodetection, leading to enhanced photo-responsivity and sensitivity compared to conventional TiO2-based devices, thereby establishing Sb:TiO2 structures as promising candidates for UV sensing applications.
{"title":"Responsivity enhancement of TiO2 based UV photodetector by antimony doping","authors":"Yusuf Shehu , Alghareeb Abbas A. M , Naser M. Ahmed , Sameen Aslam , Siti Azrah Mohamad Samsuri , W. M. Edmund Loh","doi":"10.1016/j.ijleo.2024.172188","DOIUrl":"10.1016/j.ijleo.2024.172188","url":null,"abstract":"<div><div>The excellent photoelectric properties, high stability, and low-cost fabrication have gained TiO<sub>2</sub> tremendous attention as a cutting-edge material for various energy-related applications. However, the bandgap energy in the UV range and the low excited states of TiO<sub>2</sub> have urged researchers to incorporate different dopant elements to optimize its properties. We demonstrated the effect of antimony (Sb) incorporation to TiO<sub>2</sub> as UV photodetector using chemical bath deposition technique. The structural, optical, and electrical behaviour of undoped and doped devices (Sb:TiO<sub>2</sub>) were analyzed. Under UV irradiation at a wavelength of 365 nm and a power intensity of 130 μW, we achieved remarkable enhancement in device sensitivity. Compared to an undoped device (TiO<sub>2</sub>-Ns/PSi/Ag), the doped device (Sb:TiO<sub>2</sub>-Ns/PSi/Ag) demonstrated superior photoresponse and performance. The device exhibited Schottky characteristics within a voltage range of -5V to 5 V, demonstrating strong responsiveness and excellent electrical behaviour. <em>I-V</em> analysis at bias voltages of 3 V, and 5 V revealed outstanding responsivity and sensitivity. The best optimized performance device (Sb:TiO<sub>2</sub>-Ns/PSi/Ag) demonstrate highest photodetector parameters of responsivity as 23.5 A/W, quantum efficiency as ∼8 × 10<sup>3</sup>%, sensitivity as 685.71 %, gain as 7.86, detectivity as 1.97 × 10<sup>12</sup> Jones, and NEP as 9.0 × 10<sup>–14</sup> W compared to that of the undoped TiO<sub>2</sub> device (TiO<sub>2</sub>-Ns/PSi/Ag) with responsivity of 15.4 A/W, quantum efficiency as 5.22 × 10<sup>3</sup>%, sensitivity as 420.81 %, gain as 5.21 detectivity as 1.25 × 10<sup>12</sup> Jones, and NEP as 1.42 × 10<sup>–13</sup> W, as a results of Sb incorporation to TiO<sub>2</sub> both under UV light illumination (wavelength 365 nm and power intensity of 130 <em>μW</em>) at 5 V bias voltage. These findings underscore the significant impact of Sb doping on TiO<sub>2</sub> for photodetection, leading to enhanced photo-responsivity and sensitivity compared to conventional TiO<sub>2</sub>-based devices, thereby establishing Sb:TiO<sub>2</sub> structures as promising candidates for UV sensing applications.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"321 ","pages":"Article 172188"},"PeriodicalIF":3.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143181661","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ijleo.2024.172174
Nikita Ahlawat , Bhumika Sahu , Love Bansal , Deb Kumar Rath , Subin Kaladi Chondath , Rajesh Kumar
The development of smart windows requires highly efficient electrochromic electrodes with fast response time and high optical modulation hence material synthesis parameters need to be optimized to get a material to give best possible performance. In this work, a set of Co3O4 films was prepared by electrodeposition in a constant current mode where the concentration of NaNO3 and annealing temperatures were kept as variables. All the Co3O4 films exhibited noticeable bias induced color modulation from yellow to brown, which is characterized using bias-dependent in-situ transmission spectroscopy. An optical-modulation of 64 % (at 650 nm) could get observed for the Co3O4 films prepared using 0.05 M NaNO3 and annealed at 250 °C. A very fast response time of 2.2 s/1 s for switching from colored to bleached state and vice versa. The coloration efficiency was 58.9 cm2/C for Co3O4 films synthesized using 0.05 M NaNO3 and annealed at 150 °C, due to the electrode's highly porous nature. These enhancements make cobalt oxide electrodes a suitable choice as an anodic electrode for designing solid-state electrochromic devices in real-life applications. A recipe for designing a performance based electrochromic smart film has been obtained based on the correlation between the deposition parameter and their electrochromic performance.
{"title":"Performance specific recipe for nano-Co3O4 based electrochromic electrodes: Optimizing color modulation parameters","authors":"Nikita Ahlawat , Bhumika Sahu , Love Bansal , Deb Kumar Rath , Subin Kaladi Chondath , Rajesh Kumar","doi":"10.1016/j.ijleo.2024.172174","DOIUrl":"10.1016/j.ijleo.2024.172174","url":null,"abstract":"<div><div>The development of smart windows requires highly efficient electrochromic electrodes with fast response time and high optical modulation hence material synthesis parameters need to be optimized to get a material to give best possible performance. In this work, a set of Co<sub>3</sub>O<sub>4</sub> films was prepared by electrodeposition in a constant current mode where the concentration of NaNO<sub>3</sub> and annealing temperatures were kept as variables. All the Co<sub>3</sub>O<sub>4</sub> films exhibited noticeable bias induced color modulation from yellow to brown, which is characterized using bias-dependent in-situ transmission spectroscopy. An optical-modulation of 64 % (at 650 nm) could get observed for the Co<sub>3</sub>O<sub>4</sub> films prepared using 0.05 M NaNO<sub>3</sub> and annealed at 250 °C. A very fast response time of 2.2 s/1 s for switching from colored to bleached state and vice versa. The coloration efficiency was 58.9 cm<sup>2</sup>/C for Co<sub>3</sub>O<sub>4</sub> films synthesized using 0.05 M NaNO<sub>3</sub> and annealed at 150 °C, due to the electrode's highly porous nature. These enhancements make cobalt oxide electrodes a suitable choice as an anodic electrode for designing solid-state electrochromic devices in real-life applications. A recipe for designing a performance based electrochromic smart film has been obtained based on the correlation between the deposition parameter and their electrochromic performance.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"321 ","pages":"Article 172174"},"PeriodicalIF":3.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182069","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ijleo.2024.172158
Shubhranil Maity , Uttam Kumar Samanta , Sourav Das Chowdhury , Debasis Pal , Atasi Pal
Nonlinear loop mirrors are widely used as an artificial saturable absorber to design passive mode-locked fiber lasers. Theoretical estimation shows that the nonlinear absorbing loop mirror (NAbLM) in ‘figure-8’ architecture can provide higher modulation depth and generate a larger extinction ratio over other conventional loop mirrors. The transmissivity of both the NAbLM and non-linear amplifying loop mirror (NALM) has been calculated and compared. Accordingly, a mode-locked Thulium fiber laser at around 2 µm has been designed using an NAbLM-based laser cavity. In the stable state, square-shaped broadband noise-like pulses of 3 ns at a repetition rate of 1.77 MHz have been obtained with a pulse energy of 141 nJ.
{"title":"Dynamics of Noise-like pulses in a Thulium-doped mode-locked fiber laser based on a non-linear absorbing loop mirror","authors":"Shubhranil Maity , Uttam Kumar Samanta , Sourav Das Chowdhury , Debasis Pal , Atasi Pal","doi":"10.1016/j.ijleo.2024.172158","DOIUrl":"10.1016/j.ijleo.2024.172158","url":null,"abstract":"<div><div>Nonlinear loop mirrors are widely used as an artificial saturable absorber to design passive mode-locked fiber lasers. Theoretical estimation shows that the nonlinear absorbing loop mirror (NAbLM) in ‘figure-8’ architecture can provide higher modulation depth and generate a larger extinction ratio over other conventional loop mirrors. The transmissivity of both the NAbLM and non-linear amplifying loop mirror (NALM) has been calculated and compared. Accordingly, a mode-locked Thulium fiber laser at around 2 µm has been designed using an NAbLM-based laser cavity. In the stable state, square-shaped broadband noise-like pulses of 3 ns at a repetition rate of 1.77 MHz have been obtained with a pulse energy of 141 nJ.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"321 ","pages":"Article 172158"},"PeriodicalIF":3.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182070","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}
This article explores the theoretical optimization and performance analysis of a surface plasmon resonance sensor utilizing a single-mode D-shaped polymer optical fiber for the detection of cadmium ions. In this structure, a sensing layer made of polyvinylpyrrolidone is employed over metal to protect it from environmental chemical reactions and selective sensing application of cadmium ions. Numerical investigations of the proposed structure have been carried out employing the finite element method. By optimizing the thickness of the metal, residual cladding, and sensing layer, the sensitivity and detection accuracy of the surface plasmon resonance sensor are estimated. The proposed sensor can detect the cadmium ions of concentration ranging from 0.5 ppm to 1000 ppm. The highest sensitivity (1500 nm/RIU), detection accuracy (29.6921), and figure of merit (64.4640 /RIU) of proposed sensors is observed at 1 ppm concentration of cadmium ions. Despite some variation, the detection accuracy and figure of merit remain high across all considered concentrations of cadmium ions, indicating the reliable performance of the sensor. Its optimal performance at lower concentrations is particularly beneficial for early detection and continuous monitoring of cadmium contamination.
{"title":"Optimization and performance analysis of a D-shaped polymer optical fiber SPR sensor for selective detection of cadmium ions","authors":"Ankit Mishra , Rajiv Maurya , Abhishek Upadhyay , Gaurav Sharma , Pushpender Kumar Gangwar , Vivekanand Mishra , Vivek Singh","doi":"10.1016/j.ijleo.2024.172161","DOIUrl":"10.1016/j.ijleo.2024.172161","url":null,"abstract":"<div><div>This article explores the theoretical optimization and performance analysis of a surface plasmon resonance sensor utilizing a single-mode D-shaped polymer optical fiber for the detection of cadmium ions. In this structure, a sensing layer made of polyvinylpyrrolidone is employed over metal to protect it from environmental chemical reactions and selective sensing application of cadmium ions. Numerical investigations of the proposed structure have been carried out employing the finite element method. By optimizing the thickness of the metal, residual cladding, and sensing layer, the sensitivity and detection accuracy of the surface plasmon resonance sensor are estimated. The proposed sensor can detect the cadmium ions of concentration ranging from 0.5 ppm to 1000 ppm. The highest sensitivity (1500 nm/RIU), detection accuracy (29.6921), and figure of merit (64.4640 /RIU) of proposed sensors is observed at 1 ppm concentration of cadmium ions. Despite some variation, the detection accuracy and figure of merit remain high across all considered concentrations of cadmium ions, indicating the reliable performance of the sensor. Its optimal performance at lower concentrations is particularly beneficial for early detection and continuous monitoring of cadmium contamination.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"321 ","pages":"Article 172161"},"PeriodicalIF":3.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182063","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}
This study explores the structural and optical properties of Coomassie Brilliant Blue G-250 (CBBG) using X-ray diffraction (XRD) and spectroscopic techniques. XRD analysis of both powder and thin film samples reveals distinct structural features: the powder exhibits a polycrystalline structure with strong diffraction peaks corresponding to cubic lattice planes, while the thin film shows a mix of crystalline orientations within an amorphous matrix. The Williamson-Hall relation is applied to determine average crystallite sizes, yielding 85.5 nm for the powder and 71.8 nm for the thin film, indicating their nanocrystalline nature. Microstrain analysis also reveals compressive strain within the thin film. These structural insights are critical for understanding CBBG's mechanical and optical properties, vital for biochemical and optoelectronic applications. Density functional theory (DFT) calculations with the B3LYP/6–311++G(d,p) basis set were used to optimize the molecular geometry and analyze HOMO-LUMO energies and reactive sites via the MEP map. CBBG shows higher hyperpolarizability than urea, indicating its potential for nonlinear optical applications. Miller indices further support its optoelectronic optimization. The real (ε1) and imaginary (ε2) parts of the dielectric constant were analyzed, revealing CBBG thin films exhibit strong polarization and charge displacement, influenced by structural disorder. Additionally, the volume and surface energy loss functions (VELF and SELF) highlight significant internal energy dissipation, emphasizing CBBG's potential for optoelectronic devices. The complex optical conductivity analysis reveals key absorption and dispersion behaviors essential for advanced photonic and electronic device design.
{"title":"Advanced study of structural and optical characteristics of nanocrystalline coomassie brilliant blue G-250 for optoelectronic device optimization","authors":"M.S. Moqbel , A.H. Ammar , Al-Shimaa Badran , A.A.M. Farag","doi":"10.1016/j.ijleo.2024.172147","DOIUrl":"10.1016/j.ijleo.2024.172147","url":null,"abstract":"<div><div>This study explores the structural and optical properties of Coomassie Brilliant Blue G-250 (CBBG) using X-ray diffraction (XRD) and spectroscopic techniques. XRD analysis of both powder and thin film samples reveals distinct structural features: the powder exhibits a polycrystalline structure with strong diffraction peaks corresponding to cubic lattice planes, while the thin film shows a mix of crystalline orientations within an amorphous matrix. The Williamson-Hall relation is applied to determine average crystallite sizes, yielding 85.5 nm for the powder and 71.8 nm for the thin film, indicating their nanocrystalline nature. Microstrain analysis also reveals compressive strain within the thin film. These structural insights are critical for understanding CBBG's mechanical and optical properties, vital for biochemical and optoelectronic applications. Density functional theory (DFT) calculations with the B3LYP/6–311++G(d,p) basis set were used to optimize the molecular geometry and analyze HOMO-LUMO energies and reactive sites via the MEP map. CBBG shows higher hyperpolarizability than urea, indicating its potential for nonlinear optical applications. Miller indices further support its optoelectronic optimization. The real (ε<sub>1</sub>) and imaginary (ε<sub>2</sub>) parts of the dielectric constant were analyzed, revealing CBBG thin films exhibit strong polarization and charge displacement, influenced by structural disorder. Additionally, the volume and surface energy loss functions (VELF and SELF) highlight significant internal energy dissipation, emphasizing CBBG's potential for optoelectronic devices. The complex optical conductivity analysis reveals key absorption and dispersion behaviors essential for advanced photonic and electronic device design.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"321 ","pages":"Article 172147"},"PeriodicalIF":3.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182061","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ijleo.2024.172155
Ahmet Gürkan Yüksek , Sabit Horoz , İsmail Altuntaş , İlkay Demi̇r , Ebru Ş. Tüzemen
NiO films with different thicknesses (100, 150, 200, 250, 300 and 400 nm) were grown on glass substrates using the RF Magnetron sputtering method and their optical transmittance properties were analysed with a spectrophotometer. An innovative aspect of this work was the application of machine learning techniques used to derive new insights from experimental data. Four different machine learning algorithms -ANFIS, Artificial Neural Networks (ANN), Support Vector Machines (SVM) and Gaussian Process Regression (GPR)- were tested. While the models were trained using films of different thicknesses, a randomly selected 75 % of the whole dataset was used for model testing and the remaining 25 % of the films were used for testing the models. Among these, ANN and GPR models were found to be the most successful models. Using these models, the energy band gaps were estimated at 1 nm intervals and the values ranged from approximately 3.50 eV to 3.76 eV.
{"title":"Predicting optical properties of NiO films fabricated by RF magnetron sputtering: A machine learning approach","authors":"Ahmet Gürkan Yüksek , Sabit Horoz , İsmail Altuntaş , İlkay Demi̇r , Ebru Ş. Tüzemen","doi":"10.1016/j.ijleo.2024.172155","DOIUrl":"10.1016/j.ijleo.2024.172155","url":null,"abstract":"<div><div>NiO films with different thicknesses (100, 150, 200, 250, 300 and 400 nm) were grown on glass substrates using the RF Magnetron sputtering method and their optical transmittance properties were analysed with a spectrophotometer. An innovative aspect of this work was the application of machine learning techniques used to derive new insights from experimental data. Four different machine learning algorithms -ANFIS, Artificial Neural Networks (ANN), Support Vector Machines (SVM) and Gaussian Process Regression (GPR)- were tested. While the models were trained using films of different thicknesses, a randomly selected 75 % of the whole dataset was used for model testing and the remaining 25 % of the films were used for testing the models. Among these, ANN and GPR models were found to be the most successful models. Using these models, the energy band gaps were estimated at 1 nm intervals and the values ranged from approximately 3.50 eV to 3.76 eV.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"321 ","pages":"Article 172155"},"PeriodicalIF":3.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182068","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ijleo.2024.172178
Shu Liu , Jingxuan Guo , Beier Liang , Yong Cheng , Xiumei Wang , Jing Chen
Microcavity structures with whispering-gallery modes (WGMs) have significant applications in developing advanced optical devices, making them a cornerstone in the field of optics. However, the identification of high-order WGMs remains challenging due to their smaller mode volume and higher optical field density. To address this issue, we construct a dataset of WGMs consisting of 1869 images and evaluate its performance using the YOLO algorithm. Furthermore, architectural modifications are introduced to enhance the algorithm's prediction accuracy, achieving an 8.6 % increase in mAP compared to the baseline. The improved model demonstrates reliable performance in predicting the order of WGMs, providing a valuable approach to solving the recognition challenges associated with complex optical modes.
{"title":"Prediction of the whispering-gallery modes in spherical hyperbolic metamaterial cavity based on deep learning","authors":"Shu Liu , Jingxuan Guo , Beier Liang , Yong Cheng , Xiumei Wang , Jing Chen","doi":"10.1016/j.ijleo.2024.172178","DOIUrl":"10.1016/j.ijleo.2024.172178","url":null,"abstract":"<div><div>Microcavity structures with whispering-gallery modes (WGMs) have significant applications in developing advanced optical devices, making them a cornerstone in the field of optics. However, the identification of high-order WGMs remains challenging due to their smaller mode volume and higher optical field density. To address this issue, we construct a dataset of WGMs consisting of 1869 images and evaluate its performance using the YOLO algorithm. Furthermore, architectural modifications are introduced to enhance the algorithm's prediction accuracy, achieving an 8.6 % increase in mAP compared to the baseline. The improved model demonstrates reliable performance in predicting the order of WGMs, providing a valuable approach to solving the recognition challenges associated with complex optical modes.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"321 ","pages":"Article 172178"},"PeriodicalIF":3.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143183064","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}
Pub Date : 2025-02-01DOI: 10.1016/j.ijleo.2024.172134
Robert R. Alfano , Shah Faisal B. Mazhar
This paper expands upon previous reports based on the EM Kerr model-based HHG simulation from the carrier-envelope phase (CEP) of the electromagnetic laser light wave based on electronic self-phase modulation (ESPM) from the optical Kerr index. The underpinning mechanism described for generating HHG arises from the CEP of the nonlinear index of refraction, which yields a series of Bessel functions. The envelope of the electric field E(t) of the intense ultrashort light pulses drives the CEP, resulting in many Bessel functions, one of the salient features of HHG. The HHG from the large number of Bessel function modes can produce attosecond pulses and possibly can even produce zeptosecond pulses by Kerr mode-locking among the large number N of Bessel functions.
{"title":"Higher harmonic generation arising from the bessel function expansions of the carrier-envelope-phase driven by the femtosecond optical Kerr effect","authors":"Robert R. Alfano , Shah Faisal B. Mazhar","doi":"10.1016/j.ijleo.2024.172134","DOIUrl":"10.1016/j.ijleo.2024.172134","url":null,"abstract":"<div><div>This paper expands upon previous reports based on the EM Kerr model-based HHG simulation from the carrier-envelope phase (CEP) of the electromagnetic laser light wave based on electronic self-phase modulation (ESPM) from the optical Kerr index. The underpinning mechanism described for generating HHG arises from the CEP of the nonlinear index of refraction, which yields a series of Bessel functions. The envelope of the electric field E(t) of the intense ultrashort light pulses drives the CEP, resulting in many Bessel functions, one of the salient features of HHG. The HHG from the large number of Bessel function modes can produce attosecond pulses and possibly can even produce zeptosecond pulses by Kerr mode-locking among the large number N of Bessel functions.</div></div>","PeriodicalId":19513,"journal":{"name":"Optik","volume":"321 ","pages":"Article 172134"},"PeriodicalIF":3.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182062","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号