Pub Date : 2024-01-19DOI: 10.1016/j.photonics.2024.101229
Mohammad Eskandari, Amir Habibzadeh-Sharif
In this study, we developed a novel method based on uniform and graded gratings on the front surface of ultra-thin film Si solar cells to enhance light absorption. The proposed gratings were designed in two configurations comprising penetration into the active layer and placement on it. These structures enhance absorption by scattering and diffracting light, and enlarging the optical path for photons. Simulations based on the finite element method and finite difference time domain technique showed that the graded gratings could significantly enhance absorption in the visible and infrared regions. The maximum current density and efficiency achieved for graded gratings placed on the top surface of the active layer were 21.7 mA/cm2 and 23.9%, respectively (47.6% and 48.4% higher compared with the reference cell).
{"title":"Enhancement of light absorption by ultra-thin film solar cells using graded gratings","authors":"Mohammad Eskandari, Amir Habibzadeh-Sharif","doi":"10.1016/j.photonics.2024.101229","DOIUrl":"https://doi.org/10.1016/j.photonics.2024.101229","url":null,"abstract":"<div><p><span>In this study, we developed a novel method based on uniform and graded gratings on the front surface of ultra-thin film Si solar cells to enhance light absorption<span><span>. The proposed gratings were designed in two configurations comprising penetration into the active layer and placement on it. These structures enhance absorption by scattering and diffracting light, and enlarging the optical path for photons. Simulations based on the </span>finite element method and finite difference time domain technique showed that the graded gratings could significantly enhance absorption in the visible and infrared regions. The maximum current density and efficiency achieved for graded gratings placed on the top surface of the active layer were 21.7 mA/cm</span></span><sup>2</sup> and 23.9%, respectively (47.6% and 48.4% higher compared with the reference cell).</p></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139548380","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 : 2024-01-10DOI: 10.1016/j.photonics.2024.101226
Anil Kumar, Sarvesh K. Dubey, Awadhesh Kumar, S.K. Srivastava
In this study, we introduce a metamaterial absorber operating in the near infrared region. The current metamaterial absorber (MMA) comprising Silver-SiC-Gold demonstrates an absorptivity exceeding 80% within the wavelength range of 770 nm to 1150 nm. The current metamaterials absorber exhibits independence from both polarization and incident angle. Additionally, we made comparison between the proposed Metal-Insulator-Metal (MIM) based MMA with other previously reported MMA using Silicon Carbide (SiC) and another dielectric spacer layer.
{"title":"A near infrared MIM metamaterial absorber using SiC","authors":"Anil Kumar, Sarvesh K. Dubey, Awadhesh Kumar, S.K. Srivastava","doi":"10.1016/j.photonics.2024.101226","DOIUrl":"https://doi.org/10.1016/j.photonics.2024.101226","url":null,"abstract":"<div><p><span>In this study, we introduce a metamaterial absorber operating in the </span>near infrared<span><span> region. The current metamaterial absorber (MMA) comprising Silver-SiC-Gold demonstrates an absorptivity exceeding 80% within the wavelength range of 770 nm to 1150 nm. The current metamaterials absorber exhibits independence from both polarization and incident angle. Additionally, we made comparison between the proposed Metal-Insulator-Metal (MIM) based MMA with other previously reported MMA using Silicon Carbide (SiC) and another </span>dielectric spacer layer.</span></p></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139433929","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 : 2024-01-02DOI: 10.1016/j.photonics.2023.101225
Ekaterina V. Gunina, Pavel V. Alekseevskiy, Yuliya Kenzhebaeva, Yuri A. Mezenov, Valentin A. Milichko
Detection of extreme temperatures plays a key role in metallurgy, aerospace, nuclear industries, and even astronomy. Herein, materials and optical technologies capable of detecting the temperatures above 3000 K are still in their infancy. Here, we report on a detection of 3800 to 4500 K through the emission of a blackbody, for which the metal-organic frameworks (MOFs) are used. The rapid heating of MOFs by laser radiation leads to the threshold blackbody emission (centered from 650 to 750 nm), the corresponding temperature of which is directly related to the structure of MOF. The results on such structure-related temperatures of the blackbody emission of MOFs, thereby, expand their use in photonics and sensing in general.
{"title":"Detection of extreme temperatures via emission from MOFs of a varied structure","authors":"Ekaterina V. Gunina, Pavel V. Alekseevskiy, Yuliya Kenzhebaeva, Yuri A. Mezenov, Valentin A. Milichko","doi":"10.1016/j.photonics.2023.101225","DOIUrl":"10.1016/j.photonics.2023.101225","url":null,"abstract":"<div><p><span>Detection of extreme temperatures plays a key role in metallurgy, aerospace, nuclear industries, and even astronomy. Herein, materials and optical technologies capable of detecting the temperatures above 3000 K are still in their infancy. Here, we report on a detection of 3800 to 4500 K through the emission of a blackbody, for which the metal-organic frameworks (MOFs) are used. The rapid heating of MOFs by </span>laser radiation<span> leads to the threshold blackbody emission (centered from 650 to 750 nm), the corresponding temperature of which is directly related to the structure of MOF. The results on such structure-related temperatures of the blackbody emission of MOFs, thereby, expand their use in photonics and sensing in general.</span></p></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139102753","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 : 2023-12-15DOI: 10.1016/j.photonics.2023.101224
Araz Siabi-Garjan
Using the previously introduced modified discrete dipole approximation (DDA) method by applying the full details of the nanoparticle and its surrounding environment, the detection sensitivity of molecules by plasmonic Rod-based nanosensors, including U-shaped and Rod-shaped structures, was investigated. In the calculations, the two factors of the magnitude of the wavelength shift and the ability to distinguish molecules with similar properties were of significant interest. The results indicated that the sensitivity of Rod-based nanostructures is significantly higher than that of spherical nanoparticles. Among the plasmonic Rod-based nanosensors, the silver U-shaped structure performs better than others. The wavelength shift of the absorption spectrum of different nanosensors for a given molecule was very different, making it possible to detect very similar molecules from each other by testing different sensors.
利用先前引入的修正离散偶极近似(DDA)方法,通过应用纳米粒子及其周围环境的全部细节,研究了基于等离子棒的纳米传感器(包括 U 型和棒型结构)对分子的检测灵敏度。在计算过程中,波长偏移的幅度和区分性质相似的分子的能力这两个因素受到了极大关注。结果表明,Rod 型纳米结构的灵敏度明显高于球形纳米粒子。在基于杆的质子纳米传感器中,银 U 形结构的性能优于其他结构。不同的纳米传感器对特定分子的吸收光谱的波长偏移大不相同,因此可以通过测试不同的传感器来检测彼此非常相似的分子。
{"title":"A comprehensive study on the Rod-based plasmonic structures sensing using the modified discrete dipole approximation method","authors":"Araz Siabi-Garjan","doi":"10.1016/j.photonics.2023.101224","DOIUrl":"10.1016/j.photonics.2023.101224","url":null,"abstract":"<div><p><span>Using the previously introduced modified discrete dipole approximation (DDA) method by applying the full details of the </span>nanoparticle<span><span> and its surrounding environment, the detection sensitivity of molecules by plasmonic Rod-based nanosensors, including U-shaped and Rod-shaped structures, was investigated. In the calculations, the two factors of the magnitude of the wavelength shift and the ability to distinguish molecules with similar properties were of significant interest. The results indicated that the sensitivity of Rod-based </span>nanostructures<span> is significantly higher than that of spherical nanoparticles. Among the plasmonic Rod-based nanosensors, the silver U-shaped structure performs better than others. The wavelength shift of the absorption spectrum of different nanosensors for a given molecule was very different, making it possible to detect very similar molecules from each other by testing different sensors.</span></span></p></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138818605","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 : 2023-12-14DOI: 10.1016/j.photonics.2023.101223
Callum J. Stirling , Milos Nedeljkovic , Colin Mitchell , David J. Rowe , Goran Z. Mashanovich
Mid-infrared spectroscopy enabled by silicon photonics has received great interest in recent years as a pathway for a scalable sensing technology. The development of such devices would realise inexpensive and accessible instrumentation for a wide variety of uses over numerous fields. However, not every sensing application is the same; to produce sensors for real-world scenarios, engineers need flexibility in device design but also need to maintain compatibility with scalable fabrication processes. Sub-wavelength gratings can offer a solution to this problem, as they enable the engineering of optical properties using standard fabrication techniques and without requiring new materials. By using sub-wavelength gratings, specific design approaches can be tailored to different applications, such as increasing the interaction of a sensor with an analyte or broadening the bandwidth of an integrated photonic device. Here, we review the development of sub-wavelength grating-based devices for mid-infrared silicon photonics and discuss how they can be exploited for spectroscopic and sensing devices.
{"title":"Sub-wavelength gratings in silicon photonic devices for mid-infrared spectroscopy and sensing","authors":"Callum J. Stirling , Milos Nedeljkovic , Colin Mitchell , David J. Rowe , Goran Z. Mashanovich","doi":"10.1016/j.photonics.2023.101223","DOIUrl":"10.1016/j.photonics.2023.101223","url":null,"abstract":"<div><p>Mid-infrared spectroscopy enabled by silicon photonics has received great interest in recent years as a pathway for a scalable sensing technology. The development of such devices would realise inexpensive and accessible instrumentation for a wide variety of uses over numerous fields. However, not every sensing application is the same; to produce sensors for real-world scenarios, engineers need flexibility in device design but also need to maintain compatibility with scalable fabrication processes. Sub-wavelength gratings can offer a solution to this problem, as they enable the engineering of optical properties using standard fabrication techniques and without requiring new materials. By using sub-wavelength gratings, specific design approaches can be tailored to different applications, such as increasing the interaction of a sensor with an analyte or broadening the bandwidth of an integrated photonic device. Here, we review the development of sub-wavelength grating-based devices for mid-infrared silicon photonics and discuss how they can be exploited for spectroscopic and sensing devices.</p></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1569441023001177/pdfft?md5=ffe7d777c94b1082db7487e7510a45a3&pid=1-s2.0-S1569441023001177-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138686897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-13DOI: 10.1016/j.photonics.2023.101222
Semyon V. Bachinin, Anastasia Lubimova, Artem Polushkin, Sergei S. Rzhevskii, Maria Timofeeva, Valentin A. Milichko
Metal–organic frameworks (MOFs) have recently emerged as a new class of functional materials for opto- and micro-electronic applications. Herein, the transition from laboratory samples of devices to their prototypes remains a challenge. Here we report a prototype of memristive device based on MOF (HKUST-1). The MOF thin film with a thickness of 130 nm and a size of 1 × 1 in. has been fabricated Layer-by-layer technique on a conductive substrate followed by the deposition of top Ag contacts. A fully automated process of applying voltage to write the binary data (at 0.8 ± 0.1 V), read it (by 0.4 V) and then erase (by inverted polarity with 0.4 ± 0.1 V) made it potentially possible to process arbitrary words for at least 10 cycles. The provided prototype, consisting of 10 × 10 memory cells, opens up prospects for real-life application of MOF-based logic elements, as well as reveals the challenges for their fabrication and exploitation.
{"title":"MOF thin film memristor prototype of 10×10 memory cells for automated electronic data recording","authors":"Semyon V. Bachinin, Anastasia Lubimova, Artem Polushkin, Sergei S. Rzhevskii, Maria Timofeeva, Valentin A. Milichko","doi":"10.1016/j.photonics.2023.101222","DOIUrl":"10.1016/j.photonics.2023.101222","url":null,"abstract":"<div><p>Metal–organic frameworks (MOFs) have recently emerged as a new class of functional materials<span> for opto- and micro-electronic applications. Herein, the transition from laboratory samples of devices to their prototypes remains a challenge. Here we report a prototype of memristive device based on MOF (HKUST-1). The MOF thin film with a thickness of 130 nm and a size of 1 × 1 in. has been fabricated Layer-by-layer technique on a conductive substrate followed by the deposition of top Ag contacts. A fully automated process of applying voltage to write the binary data (at 0.8 ± 0.1 V), read it (by 0.4 V) and then erase (by inverted polarity with 0.4 ± 0.1 V) made it potentially possible to process arbitrary words for at least 10 cycles. The provided prototype, consisting of 10 × 10 memory cells, opens up prospects for real-life application of MOF-based logic elements, as well as reveals the challenges for their fabrication and exploitation.</span></p></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138687157","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}
The selection of a suitable plasmonic material is crucial for achieving high-performance photonic crystal fiber-based surface plasmon resonance (PCF-SPR) sensors. However, most numerical investigations have been limited to PCF-SPR sensors with conventional circularly coated plasmonic metals due to their availability and rigid properties. In this work, a single-core arc-shaped PCF is designed and studied with sensing ingredients coated outside the fiber. The simulation and numerical analyses are performed using the full-vector finite element method to examine the effects of using gold as an active metal and also the deposition of Ta2O5 on gold. The results show that the arc-shaped sensor with gold film can obtain the maximum wavelength interrogation sensitivity (WIS) of 9500 nm/RIU within the refractive index (RI) range of 1.25–1.39 while the maximum amplitude interrogation sensitivity (AIS) reaches 579.26 RIU−1 at 1.39 and resolution is 1.05 × 10−5. However, depositing Ta2O5 on the gold gives an improved maximum WIS and AIS of 22,000 nm/RIU and 1209.21 RIU−1, respectively. With the coating of Ta2O5, the resolution improves to 4.55 × 10−6, making the proposed sensor design undoubtedly effective in detecting food chemicals such as butyl acetate and hydrocarbons along with different bio-analyte samples with a wide range of RI.
{"title":"Design and analysis of arc-shaped single core photonic crystal fiber sensor based on surface plasmon resonance","authors":"Tasmiah Tunazzina , Fairuz Areefin Khan , Anuva Chowdhury","doi":"10.1016/j.photonics.2023.101218","DOIUrl":"10.1016/j.photonics.2023.101218","url":null,"abstract":"<div><p><span><span><span>The selection of a suitable plasmonic material is crucial for achieving high-performance photonic crystal fiber-based </span>surface plasmon resonance (PCF-SPR) sensors. However, most numerical investigations have been limited to PCF-SPR sensors with conventional circularly coated plasmonic metals due to their availability and rigid properties. In this work, a single-core arc-shaped PCF is designed and studied with sensing ingredients coated outside the fiber. The simulation and numerical analyses are performed using the full-vector </span>finite element method to examine the effects of using gold as an active metal and also the deposition of Ta</span><sub>2</sub>O<sub>5</sub><span> on gold. The results show that the arc-shaped sensor with gold film can obtain the maximum wavelength interrogation sensitivity (WIS) of 9500 nm/RIU within the refractive index (RI) range of 1.25–1.39 while the maximum amplitude interrogation sensitivity (AIS) reaches 579.26 RIU</span><sup>−1</sup> at 1.39 and resolution is 1.05 × 10<sup>−5</sup>. However, depositing Ta<sub>2</sub>O<sub>5</sub> on the gold gives an improved maximum WIS and AIS of 22,000 nm/RIU and 1209.21 RIU<sup>−1</sup>, respectively. With the coating of Ta<sub>2</sub>O<sub>5</sub>, the resolution improves to 4.55 × 10<sup>−6</sup>, making the proposed sensor design undoubtedly effective in detecting food chemicals such as butyl acetate and hydrocarbons along with different bio-analyte samples with a wide range of RI.</p></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138581529","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 : 2023-12-10DOI: 10.1016/j.photonics.2023.101220
Irina A. Gorbunova , Maria Timofeeva , Ekaterina Gunina , Yulia O. Sharavyeva , Kseniia Yu. Parkhoma , Daria A. Shipilovskikh , Sergei A. Shipilovskikh
Luminescent organic thin films are widely used in optoelectronic devices for sensing, imaging and data processing. Herein, the transition to a flexible form is accompanied by a number of challenges associated with a limited endurance and bending-dependent properties. Here we report a study on the growth of thin films based on thiophene-based luminescent molecular crystals (MC) on a flexible polypropylene (PP) substrate of a various thicknesses (400 μm to 50 μm). The resulting flexible thin films demonstrate the stability of their luminescent properties under mechanical bending (up to 100 times) at ambient conditions, which pave the way for large scale production of planar optoelectronic components.
{"title":"Self-assembly of thiophene-based luminescent thin films on flexible substrates.","authors":"Irina A. Gorbunova , Maria Timofeeva , Ekaterina Gunina , Yulia O. Sharavyeva , Kseniia Yu. Parkhoma , Daria A. Shipilovskikh , Sergei A. Shipilovskikh","doi":"10.1016/j.photonics.2023.101220","DOIUrl":"10.1016/j.photonics.2023.101220","url":null,"abstract":"<div><p><span><span><span>Luminescent organic thin films<span> are widely used in optoelectronic<span> devices for sensing, imaging and data processing. Herein, the transition to a flexible form is accompanied by a number of challenges associated with a limited endurance and bending-dependent properties. Here we report a study on the growth of thin films based on thiophene-based luminescent </span></span></span>molecular crystals (MC) on a flexible </span>polypropylene (PP) substrate of a various thicknesses (400 </span><em>μ</em>m to 50 <em>μ</em>m). The resulting flexible thin films demonstrate the stability of their luminescent properties under mechanical bending (up to 100 times) at ambient conditions, which pave the way for large scale production of planar optoelectronic components.</p></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138581528","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 : 2023-12-09DOI: 10.1016/j.photonics.2023.101221
Muhammad Zain Siddiqui , Ahmet E. Akosman , Mustafa Ordu
A new design of polarization-maintaining and spectral filtering negative curvature hollow-core fiber tailored for the telecommunication bands in the near-infrared region is presented. The optical fiber, consisting of a six-tube silica structure, incorporates vertically nested tubes anchored radially by a pole structure. By contrast, standard nested tubes in the horizontal direction form the asymmetric fiber structure, which encounters birefringence. This unique fiber design not only preserves the polarization states of light but also exhibits frequency selective transmission exclusively in the vertical direction due to the pole structure. Through fiber design optimization, a transmission loss below 0.1 dB/km for spectrally filtered wavelengths is achieved, with birefringence on the order of 10−5 within the wavelength range of 1.45 µm to 1.60 µm. These results demonstrate significant improvements in terms of birefringence, distinct loss separation between horizontally and vertically polarized states, and a reduced number of spectrally filtered wavelengths compared to previously reported findings. The proposed fiber design holds untapped potential for applications requiring selective transmissions with specific polarization.
{"title":"Enhancing polarization maintenance and spectral filtering in negative curvature hollow-core fibers","authors":"Muhammad Zain Siddiqui , Ahmet E. Akosman , Mustafa Ordu","doi":"10.1016/j.photonics.2023.101221","DOIUrl":"10.1016/j.photonics.2023.101221","url":null,"abstract":"<div><p><span><span>A new design of polarization-maintaining and spectral filtering negative curvature hollow-core fiber tailored for the telecommunication bands in the near-infrared region is presented. The optical fiber<span>, consisting of a six-tube silica structure, incorporates vertically nested tubes anchored radially by a pole structure. By contrast, standard nested tubes in the horizontal direction form the asymmetric fiber structure, which encounters </span></span>birefringence. This unique fiber design not only preserves the polarization states of light but also exhibits frequency selective transmission exclusively in the vertical direction due to the pole structure. Through fiber design optimization, a transmission loss below </span><em>0.1 dB/km</em> for spectrally filtered wavelengths is achieved, with birefringence on the order of 10<sup>−5</sup> within the wavelength range of <em>1.45 µm</em> to <em>1.60 µm</em>. These results demonstrate significant improvements in terms of birefringence, distinct loss separation between horizontally and vertically polarized states, and a reduced number of spectrally filtered wavelengths compared to previously reported findings. The proposed fiber design holds untapped potential for applications requiring selective transmissions with specific polarization.</p></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138581401","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 : 2023-12-02DOI: 10.1016/j.photonics.2023.101219
Kang-Hyok O, Kwang-Hyon Kim
Quadrupole topological insulators have recently attracted great attention in the field of topological physics, while they are limited to square and hexagonal lattices. In this work, we theoretically show that nontrivial quadrupole topology can be obtained in generalized non-square lattice photonic crystals with translation symmetry, which are composed of parallelogram-shaped unit cells. The translation symmetry is described by the fractional linear combination of primary lattice vectors, leading to the quantization of fractional quadrupole moment in conjunction with an additional symmorphic symmetry. For parallelogramatic lattice with inversion symmetry, in particular, the quantization of the quadrupole moment is independent of the choice of primary lattice vectors, enabling cavity structures with arbitrary angles. For the change of structural parameters, quadrupole bandgaps undergo second-order topological phase transitions, accompanying with double band inversions. Nontrivial quadrupole phases are manifested by the appearance of disorder-immune in-gap corner states localized at the topological interfaces. Furthermore, the proposed parallelogramatic lattice photonic crystal has multiple quadrupole bandgaps for proper structural parameters, exhibiting multiband second-order topological corner states. The presented results will further extend the class of quadrupole topological photonic crystals and pave a broad way towards their practical applications due to improved design flexibility.
{"title":"Quadrupole photonic topological corner states in generalized non-square lattices with translation symmetry","authors":"Kang-Hyok O, Kwang-Hyon Kim","doi":"10.1016/j.photonics.2023.101219","DOIUrl":"10.1016/j.photonics.2023.101219","url":null,"abstract":"<div><p>Quadrupole<span><span> topological insulators<span><span> have recently attracted great attention in the field of topological physics, while they are limited to square and hexagonal lattices. In this work, we theoretically show that nontrivial quadrupole </span>topology can be obtained in generalized non-square lattice </span></span>photonic crystals with translation symmetry, which are composed of parallelogram-shaped unit cells. The translation symmetry is described by the fractional linear combination of primary lattice vectors, leading to the quantization of fractional quadrupole moment in conjunction with an additional symmorphic symmetry. For parallelogramatic lattice with inversion symmetry, in particular, the quantization of the quadrupole moment is independent of the choice of primary lattice vectors, enabling cavity structures with arbitrary angles. For the change of structural parameters, quadrupole bandgaps undergo second-order topological phase transitions, accompanying with double band inversions. Nontrivial quadrupole phases are manifested by the appearance of disorder-immune in-gap corner states localized at the topological interfaces. Furthermore, the proposed parallelogramatic lattice photonic crystal has multiple quadrupole bandgaps for proper structural parameters, exhibiting multiband second-order topological corner states. The presented results will further extend the class of quadrupole topological photonic crystals and pave a broad way towards their practical applications due to improved design flexibility.</span></p></div>","PeriodicalId":49699,"journal":{"name":"Photonics and Nanostructures-Fundamentals and Applications","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138542180","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}