Results in Optics最新文献

{"title":"Hydrogel-based THz wave absorber","authors":"Amir Ali Mohammad Khani ,&nbsp;Alireza Barati Haghverdi ,&nbsp;Ilghar Rezaei ,&nbsp;Ali Soldoozy ,&nbsp;Toktam Aghaee","doi":"10.1016/j.rio.2025.100810","DOIUrl":"10.1016/j.rio.2025.100810","url":null,"abstract":"<div><div>Extensive research has been conducted on graphene-based terahertz (THz) wave absorbers, fundamental components in optical systems. A significant focus of these studies has been on enhancing the adjustability of these absorbers. This work explores the use of a hydrogel spacer as a novel approach. The thickness of the hydrogel spacer is directly influenced by the ambient moisture, introducing an additional degree of freedom in tuning the system, beyond conventional methods. An analytical model based on passive circuit elements is developed to describe this mechanism, and full-wave simulations are presented in the results section to validate the concept. The discussion highlights that while most tuning methods primarily affect the absorber’s response to incident radiation, the proposed method uniquely alters the impedance of the spacer itself. This feature complements existing tuning techniques and enables new possibilities in the design of adjustable terahertz absorbers. Additionally, the obtained results from both the circuit model and full-wave simulations, verify the possibility of sweeping the entire THz gap via changing humidity. According to the simulation results, the proposed absorber can show up to eight absorption peaks over 80%. Such a simple and efficient wave absorber in a controlled environment can play a basic building block for optical sensors.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100810"},"PeriodicalIF":0.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143686340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Room temperature structural, and ferromagnetic behaviour of Mn, Fe and Mn/ Fe codoped In2O3 Nanocrystalline","authors":"Sanjay Kumar ,&nbsp;Virendra Kumar ,&nbsp;Manoj Kumar Bansal ,&nbsp;Arvind Mishra ,&nbsp;Vimlesh Mishra","doi":"10.1016/j.rio.2025.100812","DOIUrl":"10.1016/j.rio.2025.100812","url":null,"abstract":"<div><div>Manganese &amp; iron-doped indium oxide dilute magnetic semiconductor (DMS) powder was synthesized by solid-state reaction method. The effect of Mn &amp; Fe doping on magnetic, optical, and structural properties of (<em>In)_0.985</em>(Mn).₀₁₅O and (In<em>)_0.985</em>(Fe_).015O have been systematically studied. The polycrystalline cubic structure has been confirmed by an X-ray diffraction pattern. It is also being reported that the optical band gap increases from 3.8 eV to 4.2 eV for Mn-doped while 3.8 eV to 4.4 eV for Fe-doped samples. FTIR spectra reveal the occupancy of In-O and In-O-H absorption bands. EDAX confirms the occupancy of Fe, O, In, and Mn elements in the prepared samples. M−H plot indicates superparamagnetic behavior in Mn-doped In₂O₃.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100812"},"PeriodicalIF":0.0,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acousto-optic cryptosystem based on dynamic DNA encoding and hyperchaotic system in gyrator domains","authors":"Gege Sun ,&nbsp;Wenbo Song ,&nbsp;Miao Tian ,&nbsp;Zhengjun Liu ,&nbsp;Hang Chen","doi":"10.1016/j.rio.2025.100814","DOIUrl":"10.1016/j.rio.2025.100814","url":null,"abstract":"<div><div>Traditional encryption algorithms like DES suffer from the issue of key length (128 bits to 256 bits) and the inconvenience of memorization. Users typically store keys in a file or device, or even directly on a computer hard drive, releasing the key through a relatively easy-to-remember passphrase. Addressing these issues, this paper proposes a novel remote sensing image encryption system based on a hybrid model incorporating a 4D Lorenz chaotic system, Gyrator transform, Acousto-optic Conversion system, and dynamic DNA encoding. Firstly, the original image is scrambled using a 4D Lorenz mapping function. Subsequently, employing an Acousto-optic modulation algorithm, audio information is fitted into image information and serves as part of the encryption system key, significantly enhancing the correlation between the key and the user. Then, employing a dynamic DNA encoding algorithm, the image is encoded using eight different DNA encryption schemes and three distinct computational rules, achieving an exponential expansion of the key space with minimal computational overhead. Finally, through comparative analysis, the Gyrator transform, demonstrating superior performance, is selected to further encrypt remote sensing image data, expanding the key space. The proposed remote sensing image encryption system exhibits high security performance and robustness against various attacks.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100814"},"PeriodicalIF":0.0,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143686333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and fabrication of E-band silica based dense wavelength-division multiplexing (DWDM) AWG","authors":"Feng Han ,&nbsp;Jiashun Zhang ,&nbsp;Liangliang Wang ,&nbsp;Pengwei Cui ,&nbsp;Yue Wang ,&nbsp;Junming An ,&nbsp;Jun Chen ,&nbsp;Bingli Sun ,&nbsp;Tianhong Zhou","doi":"10.1016/j.rio.2025.100806","DOIUrl":"10.1016/j.rio.2025.100806","url":null,"abstract":"<div><div>A E-Band,48 channels flat top silica based dense wavelength-division multiplexing (DWDM) arrayed waveguide grating (AWG) was designed and fabricated with 0.75 % relative refractive index difference. In order to reduce the center wavelength drift caused by the refractive index of silica material changing with external environmental temperature, the AWG chip was athermal packaged, and the center wavelength drift was reduced from 8.2 pm/° C to 0.643 pm/° C. The transmission spectra were measured, which the results shows that optical performance is uniform. The tested 53.12 GBPS pam-4 high-speed transmission eye signals are clearly visible, extinction ratio is more than 2.7 DB. The high-performance AWG provides an application basis for e-band data center transmission.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100806"},"PeriodicalIF":0.0,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Studies and development of FBG based multi-point temperature sensor for vacuum chambers of synchrotron radiation source Indus-2","authors":"J. Kumar ,&nbsp;S. Kumar ,&nbsp;R. Mahakud ,&nbsp;K.V.A.N.P.S. Kumar ,&nbsp;B. Sindal ,&nbsp;D.P. Yadav ,&nbsp;P.K. Agrawal ,&nbsp;M.K. Saxena ,&nbsp;O. Prakash","doi":"10.1016/j.rio.2025.100805","DOIUrl":"10.1016/j.rio.2025.100805","url":null,"abstract":"<div><div>This paper presents the development and deployment of a multi-point fiber Bragg grating (FBG) sensor system for precise temperature monitoring along the vacuum chamber walls of dipole and Pinger magnets in Indus-2, a synchrotron radiation source. The challenging environment includes bremsstrahlung radiation (20 Rad/h), strong magnetic fields (1.5 T), and high RF fields (∼0.8 MV/m at 505.812 MHz). The sensor system was created by inscribing multiple FBGs at distinct wavelengths on a single optical fiber using the second harmonic of a copper vapor laser (CVL). The FBG array was validated for operation in high-radiation and high-voltage (∼10 kV) conditions. It was installed to monitor temperature profiles during Indus-2 operation at 2.5 GeV, 200 mA, where chamber temperatures ranged from 18 °C to 40 °C. The significance of this observation lies in its potential application for the early detection of electron beam orbit mis-steering occurrences, thereby facilitating real-time temperature monitoring and the subsequent optimization of electron beam orbit alignment. Such proactive measures are crucial for ensuring the dependable and consistent operation of Indus-2.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100805"},"PeriodicalIF":0.0,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143593583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrochemical formation of polyacrylamide-sulfur composite coatings on titanium surfaces","authors":"Khakkulov Jakhongir,&nbsp;Temirov Zokirjon","doi":"10.1016/j.rio.2025.100804","DOIUrl":"10.1016/j.rio.2025.100804","url":null,"abstract":"<div><div>In this study, titanium was chosen as the substrate material to form composite coatings that replace traditional metal sheets. Colloidal nanoparticles, which are heterogeneous in nature, exhibit variations in size, shape, and composition that significantly affect their catalytic behavior.</div><div>These variations are crucial for understanding the interactions between individual particles, as they can alter the efficiency and performance of the coating. The role of electrolysis in controlling the deposition and stability of nanoparticles on titanium surfaces is also examined.</div><div>Sulfur wastes can be recycled into functionally active products by using polyacrylamide, a flocculating agent derived from indigenous polymers. This approach aims to expand the potential applications and improve the performance of these materials under practical conditions. Therefore, research in this area is of great importance, focusing on innovative methods for converting sulfur wastes into valuable bioactive compounds.</div><div>This research focuses on the formation of a composite material based on polyacrylamide and sulfur on the surface of a titanium plate through electrolysis. The study employed scanning electron microscopy (SEM) to analyze the resulting composite material. The findings revealed that the amide groups (–CONH₂) in polyacrylamide interact effectively with sulfur, enhancing the adhesion and stability of the deposited sulfur layer. Additionally, polyacrylamide plays a critical role in stabilizing the microstructure of sulfur, facilitating the integration and uniform formation of the composite coating. This innovative approach demonstrates the potential for creating robust composite materials with promising applications.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100804"},"PeriodicalIF":0.0,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143620947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photo-stability of Chrysoidine ‘R’ dye in the presence of Lactic acid-Cocamidopropylbetaine surfactant-NaOH: A spectral study","authors":"Pooran Koli,&nbsp;Anamika Charan","doi":"10.1016/j.rio.2025.100809","DOIUrl":"10.1016/j.rio.2025.100809","url":null,"abstract":"<div><div>The photo-galvanic cells are solar cell devices capable of harvesting solar energy with power storage. The dye photo-sensitizer material is the key constituent of these cells. Thus, the chemical stability of the dye material prominently affects the electrical output, durability and photo-stability of these cells. Therefore, in present research, the photo-stability of Chrysoidine-R dye material in both the non-illuminated and illuminated conditions has been studied spectroscopically to explore it in these cells. The photo-stability of Chrysoidine-R dye has been investigated in two conditions, (i) aqueous dye solution; and (ii) electrolyte (i.e., Chrysoidine-R dye photo-sensitizer, Lactic acid reductant, Cocamidopropyl betaine surfactant, NaOH alkali, and water). The study has been done to have insight into effect of electrolyte on the photo-stability and light absorption property of Chrysoidine-R dye.</div><div>The observed data shows that absorbance of the Chrysoidine-R dye increases over two days’ illumination and it decreases after two days’ continuous illumination. Initial rise in the absorbance may be attributed to sunlight induced augmentation in the dye polarity. The downfall in absorbance after two days’ illumination may be attributed to the photo-induced dye decay occurring in the electrolyte as a result of long exposure of dye molecules to sunlight. The spectral study shows that Chrysoidine-R dye is quite less photo-stable in individual state as well as in the presence of electrolyte materials. Therefore, under the present experimental conditions, the Chrysoidine-R dye is not a suitable sensitizer material for use in sustainable photogalvanics.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100809"},"PeriodicalIF":0.0,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143579855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of optical wireless power transmission across biological tissue using NIR light considering safe irradiance level","authors":"Syifaul Fuada ,&nbsp;Mariella Särestöniemi ,&nbsp;Marcos Katz","doi":"10.1016/j.rio.2025.100801","DOIUrl":"10.1016/j.rio.2025.100801","url":null,"abstract":"<div><div>Presently, implantable electronic devices (IEDs) are becoming integral choices in medical applications, still their reliance on nonrechargeable batteries limits their longevity. This challenge has driven worldwide interest in developing rechargeable IEDs. While energy transfer based on radio-frequency (RF) has been clinically employed to address the challenge of IEDs running out of battery power, research into alternative methods, such as near-infrared (NIR) light-based energy transfer schemes, is advancing rapidly. The key advantages of optical systems are security, privacy, safety, interference-free operation, etc. The properties of NIR light are attractive for optical wireless power transmission (OWPT) across biological tissue due to minimal scattering and absorption effect. NIR light has been widely employed for various therapeutic applications, such as photobiomodulation (PBM) therapy. When using power transfer, ensuring that do not exceed safety regulations to avoid damage to the tissue is important. In this study, we investigate OWPT under safe level irradiance referring to the typical PBM applications, i.e., 20 mW/cm², 25 mW/cm², and 200 mW/cm². The OWPT system is tested on an experimental testbed, consisting of an 810 nm NIR LED and a photovoltaic (PV) cell as transmitter and receiver, respectively. A tissue-mimicking optical phantom was employed as a propagation media that has long-lasting stability at a room temperature around the testbed, thus suitable for prolonged experiments. We measure the time it takes to charge an energy-storing supercapacitor under three different safe irradiance levels to assess the feasibility of safely charging an IED’s storage. In addition, we compare the results with the maximum irradiance of NIR LED, i.e., 527 mW/cm². Comparing 527 mW/cm² to PBM irradiance revealed a trade-off between supercapacitor charging time and tissue safety. Charging limitations and other related issues are also elaborated in this paper.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100801"},"PeriodicalIF":0.0,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143620608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of a compact all-optical digital-to-analog converter based on photonic crystals using neural networks","authors":"Pouya Karami ,&nbsp;Salah I. Yahya ,&nbsp;Muhammad Akmal Chaudhary ,&nbsp;Maher Assaad ,&nbsp;Fariborz Parandin ,&nbsp;Saeed Roshani ,&nbsp;Fawwaz Hazzazi ,&nbsp;Ali Nazari ,&nbsp;Sobhan Roshani","doi":"10.1016/j.rio.2025.100802","DOIUrl":"10.1016/j.rio.2025.100802","url":null,"abstract":"<div><div>This paper presents the design and optimization of a compact 2-bit all-optical Digital-to-Analog Converter (DAC) based on photonic crystals (PCs), utilizing an Artificial Neural Network (ANN) for enhanced performance. The proposed structure features a square lattice photonic crystal composed of silicon rods in an air background, designed to operate within the photonic bandgap for the TM mode at a wavelength of 1.55 μm. The dimensions of defect rods in the photonic crystal structure are optimized using a feed forward ANN, trained with simulated data to maximize the output power of the DAC. The ANN model demonstrates high precision in predicting the optimal dimensions, achieving a significant reduction in design size and complexity. The designed DAC performance is validated through simulations using two software, and the results are consistent with predictions, confirming the validity of the design. The proposed 2-bit DAC exhibits superior performance with minimal footprint of 116 µm², making it highly suitable for integration into all-optical digital circuits and next-generation optical fiber technologies.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100802"},"PeriodicalIF":0.0,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143561812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential of radioluminescent silica-based optical fibers for 14 MeV neutron beam monitoring","authors":"Luca Weninger ,&nbsp;Adriana Morana ,&nbsp;Andrea Colangeli ,&nbsp;Fiammetta Fricano ,&nbsp;Youcef Ouerdane ,&nbsp;Emmanuel Marin ,&nbsp;Aziz Boukenter ,&nbsp;Stefano Loreti ,&nbsp;Antonino Pietropaolo ,&nbsp;Sylvain Girard","doi":"10.1016/j.rio.2025.100807","DOIUrl":"10.1016/j.rio.2025.100807","url":null,"abstract":"<div><div>The present paper proposes a solution for 14 MeV neutron beam monitoring employing Ce-doped optical fibers, based on the radiation-induced luminescence (RIL) phenomenon. Context is given on the possible use of these fiber-based monitors in fusion experiments, exploiting the advantages of optical fibers and of the proposed setup to overcome the limitations given by the harsh environments of fusion-related facilities. Here, the advantages of optical fibers (size, weight, electromagnetic immunity, among others) are complemented by the possibility of a very simple single-ended setup, which can be operated remotely, avoiding the exposure of the detectors to radiation. Two 2-cm long Ce-optical fibers were tested, one pristine and one that was X-ray pre-irradiated at 250 kGy(SiO₂). The investigated optical fibers have been characterized at the Frascati Neutron Generator (FNG) of ENEA (Italy) under 14 MeV neutrons and a flux varying between 4 × 10⁷ and 4.5 × 10⁸ n cm⁻² s⁻¹. Two runs have been performed, a first one to calibrate the RIL response to the neutron flux, via a linear fit between the facility monitors and the optical fiber response. A second run was then performed to validate the calculated sensitivity. The positive effect of pre-irradiation is demonstrated by a clear improvement in RIL response. The final results show a maximum deviation in the fluence measurements from the alpha counter of the facility of 6 % for the pristine fiber and 4 % for the pre-irradiated one, both values are lower than the 7 % deviation between the alpha counter and the fission chamber of the FNG facility.</div></div>","PeriodicalId":21151,"journal":{"name":"Results in Optics","volume":"19 ","pages":"Article 100807"},"PeriodicalIF":0.0,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143548999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}