{"title":"Single-shot pump-probe technique by the combination of an echelon and a grating with a time window of 109 ps","authors":"Tianchen Yu, Junyi Yang, Zhongguo Li, Xingzhi Wu, Yu Fang, Yong Yang, Yinglin Song","doi":"10.1088/2040-8986/ad44af","DOIUrl":"https://doi.org/10.1088/2040-8986/ad44af","url":null,"abstract":"In this study, using only a single pulse, pump-probe measurement with a large time window of more than 100 ps is implemented. A commercial grating is used to encode a time window of ∼56 ps in a single pulse; therefore, there is no need for machining customization. In addition, in this technique, the grating surface is accurately imaged, eliminating the image blur problem caused by phase differences in previous echelon-based techniques. Moreover, to make full use of the grating surface and obtain a larger time window, a simple reflection echelon is combined that matches the grating in the time window. This combination encoding strategy results in a total time window of ∼109 ps and maintains accurate imaging of the grating surface. This time window is an order of magnitude greater than the maximum reported values of the echelon encoding strategy and the angle beam encoding strategy. To demonstrate this single-shot pump-probe technique, the two-photon absorption process of ZnSe and the excited-state absorption process of a symmetrical phenoxazinium bromine salt were studied. The possibility of further improving the experimental setup is also discussed.","PeriodicalId":16775,"journal":{"name":"Journal of Optics","volume":"5 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140940164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
{"title":"Dual-optical-multiplexing-based multi-image invisible visual cryptography","authors":"Xinyu Zhang, Xiaoshuang Shen, Yupeng Zhu, Zhaoke Mi, Yusi Zhu, Huiliang Zhang, Changjun Ke, Yishi Shi","doi":"10.1088/2040-8986/ad44ac","DOIUrl":"https://doi.org/10.1088/2040-8986/ad44ac","url":null,"abstract":"In earlier research, the concept of using diffractive optics to indirectly achieve invisible visual cryptography (VC) was proposed. In this approach, the extraction process does not require complex optical implementations or additional computations. However, the system’s security and the capacity still need to be improved. Correspondingly, this paper introduces a multi-image invisible VC system based on dual optical multiplexing. Under the conditions of diffraction distance multiplexing and wavelength multiplexing, the visual keys of secret images are concealed within a phase key in the Fresnel domain. This method enhances the system’s security through dual optical multiplexing and ensures a certain capacity for information concealment. Optical experiments verify that the easy extraction and the high repeatability are all obtainable in the method.","PeriodicalId":16775,"journal":{"name":"Journal of Optics","volume":"32 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140940160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Yifei Ma, Zimo Zhao, Jiahe Cui, Jingyu Wang, Chao He
{"title":"Vectorial adaptive optics for advanced imaging systems","authors":"Yifei Ma, Zimo Zhao, Jiahe Cui, Jingyu Wang, Chao He","doi":"10.1088/2040-8986/ad4374","DOIUrl":"https://doi.org/10.1088/2040-8986/ad4374","url":null,"abstract":"Vectorial adaptive optics (V-AO) is a cutting-edge technique extending conventional AO into the vectorial domain encompassing both polarization and phase feedback correction for optical systems. However, previous V-AO approaches focus on point correction. In this letter, we extend this AO approach into the imaging domain. We show how V-AO can benefit an aberrated imaging system to enhance not only scalar imaging but also the quality of vectorial information. Two important criteria, vectorial precision and uniformity are put forward and used in practice to evaluate the performance of the correction. These experimental validations pave the way for real-world imaging for V-AO technology and its applications.","PeriodicalId":16775,"journal":{"name":"Journal of Optics","volume":"28 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140942439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
{"title":"Research on secure communication technology based on phase conjugate feedback chaotic injection system","authors":"Jingbo Fu, Penghua Mu","doi":"10.1088/2040-8986/ad44a8","DOIUrl":"https://doi.org/10.1088/2040-8986/ad44a8","url":null,"abstract":"This paper presents an experimental scheme using optical method instead of phase conjugate light. We have implemented a phase conjugate feedback semiconductor laser chaotic system based on the four-wave mixing principle through an established optical fiber experimental platform. Based on the high-dimensional wideband chaotic signals generated by this system, we propose a two-channel secure communication scheme based on phase conjugate feedback, and analyze its delay hiding mechanism and synchronization characteristics. The effects of parameter mismatch and injection strength on synchronization performance and communication quality are also considered. Our experimental results show that by adjusting the injection strength and frequency detuning parameters, the system can produce signals with time-delay signature completely suppressed, thus achieving high-quality and high-security communications.","PeriodicalId":16775,"journal":{"name":"Journal of Optics","volume":"3 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140940161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
{"title":"New 4D hyperchaotic system’s application in image encryption","authors":"Heming Xu and Jian Wang","doi":"10.1088/2040-8986/ad3e0d","DOIUrl":"https://doi.org/10.1088/2040-8986/ad3e0d","url":null,"abstract":"In order to protect sensitive information from unauthorized access and illegal copy during network transmission, storage and processing, we propose a new four-dimensional hyperchaotic system (4DHS) and apply it to encryption algorithm. Firstly, the dynamical properties of 4DHS are analyzed according to the structure, and the chaotic properties are verified by dissipation, equilibrium point and lyapunov exponent. Secondly, the chaotic sequence combined with Arnold scrambling method is adopted to scramble the pixel values of the plaintext image, and the scrambled pixel matrix is diffused into the ciphertext image matrix by XOR operation. Finally, we conduct the experiments to validate the effectiveness of the proposed encryption algorithm and achieve satisfactory results. At the same time, we compare the proposed encryption algorithm with other encryption algorithms, and the excellent encryption effect of our encryption algorithm can be proved.","PeriodicalId":16775,"journal":{"name":"Journal of Optics","volume":"37 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140829917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
{"title":"Optical momentum distributions in monochromatic, isotropic random vector fields","authors":"Titouan Gadeyne and Mark R Dennis","doi":"10.1088/2040-8986/ad3b14","DOIUrl":"https://doi.org/10.1088/2040-8986/ad3b14","url":null,"abstract":"We investigate the decomposition of the electromagnetic Poynting momentum density in three-dimensional random monochromatic fields into orbital and spin parts, using analytical and numerical methods. In sharp contrast with the paraxial case, the orbital and spin momenta in isotropic random fields are found to be identically distributed in magnitude, increasing the discrepancy between the Poynting and orbital pictures of energy flow. Spatial correlation functions reveal differences in the generic organization of the optical momenta in complex natural light fields, with the orbital current typically forming broad channels of unidirectional flow, and the spin current manifesting larger vorticity and changing direction over subwavelength distances. These results are extended to random fields with pure helicity, in relation to the inclusion of electric-magnetic democracy in the definition of optical momenta.","PeriodicalId":16775,"journal":{"name":"Journal of Optics","volume":"43 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140829905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
{"title":"Watermarking algorithm based on phase-only CGH in fractional Hartley domain for DICOM images","authors":"Raman Yadav, Sachin and Phool Singh","doi":"10.1088/2040-8986/ad3a77","DOIUrl":"https://doi.org/10.1088/2040-8986/ad3a77","url":null,"abstract":"In this manuscript, we proposed a watermarking algorithm based on phase-only computer-generated holography (CGH) in the fractional Hartley domain for digital imaging and communications in medicine (DICOM) images. The proposed algorithm improves the security of the CGH-based algorithm. The cascaded use of fractional Hartley transform and attenuation factor increases the keyspace of the proposed watermarking algorithm. The robustness and effectiveness of the proposed watermarking algorithm is validated using simulations on DICOM images. The effectiveness of the proposed watermarking algorithm is assessed using statistical tools in terms of mean-squared error, information entropy, correlation coefficient, histogram, and mesh plots. The robustness is evaluated by testing the proposed algorithm’s performance under real-time threats, including contamination and data loss attacks. Furthermore, the security of the proposed algorithm is also tested for existing cryptographic attacks, such as chosen-plaintext attacks, and known-plaintext attacks. The simulation results indicate that the proposed watermarking algorithm is robust and effective.","PeriodicalId":16775,"journal":{"name":"Journal of Optics","volume":"116 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140830430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
{"title":"Analytical solution to second-harmonic generation of ultrashort laser pulse","authors":"Yufei Peng, Chenyang Hu, Lihong Hong, Zhiyuan Li","doi":"10.1088/2040-8986/ad3b17","DOIUrl":"https://doi.org/10.1088/2040-8986/ad3b17","url":null,"abstract":"We present an analytical method to evaluate the second-harmonic generation (SHG) process of ultrashort laser pulses in a nonlinear medium within the small-signal regime. Building upon the broadband nonlinear coupled wave theory, we derive an analytical solution that allows one to investigate the fundamental physics and detailed dynamics of the nonlinear interaction between ultrashort laser pulses. We find that SHG for ultrashort laser pulses in a nonlinear crystal arises from a series of self-SHG and self sum-frequency generation processes involving different frequency components. We have applied the analytical method to investigate specific pulse profiles with Gaussian and sech functions and found good agreement between analytical theory and numerical simulations, validating the accuracy of the analytical approach. The analytical method enables one to explore the evolution of the second-harmonic wave under various pulse profiles, pulse widths, and crystal thicknesses, and offers a more efficient and insightful approach to study the nonlinear optical dynamics of ultrashort laser pulses.","PeriodicalId":16775,"journal":{"name":"Journal of Optics","volume":"49 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140608946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Resmi M, Elaganuru Bashaiah and Ramachandrarao Yalla
{"title":"Channeling of fluorescence photons from quantum dots into guided modes of an optical nanofiber tip","authors":"Resmi M, Elaganuru Bashaiah and Ramachandrarao Yalla","doi":"10.1088/2040-8986/ad3ccb","DOIUrl":"https://doi.org/10.1088/2040-8986/ad3ccb","url":null,"abstract":"We demonstrate the channeling of fluorescence photons from quantum dots (QDs) into guided modes of an optical nanofiber tip (ONFT). We deposit QDs on the ONFT using micro/nano fluidic technology. We measure the photon-counting and emission spectrum of fluorescence photons that are channeled into guided modes of the ONFT. The measured emission spectrum confirms the deposition of QDs on the ONFT. We perform numerical simulations to determine channeling efficiency (η) for the ONFT and a single dipole source (SDS) system. For the radially oriented SDS at the center of the facet of the ONFT, we found the maximum η-value of 44% at the fiber size parameter of 7.16, corresponding to the ONFT radius of 0.71 µm for the emission wavelength at 620 nm. Additionally, we investigate the SDS position dependence in transverse directions on the facet of the ONFT in view of keeping experimental ambiguities. The present fiber inline platform may open new avenues in quantum technologies.","PeriodicalId":16775,"journal":{"name":"Journal of Optics","volume":"48 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140800974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
{"title":"Enhanced circular dichroism of an X-shaped nanostructure by asymmetric surface plasmon interference","authors":"Abduweli Abdukerim, Haximjan Abdusattar","doi":"10.1088/2040-8986/ad3b15","DOIUrl":"https://doi.org/10.1088/2040-8986/ad3b15","url":null,"abstract":"A plasmonic chiral structure, which is a nanostructure composed of noble metals that lacks planar symmetry, demonstrates significant potential for various applications in bio-sensing, optical forces, switching and controlling the photoluminescence, and detecting chiral light. Understanding its fundamental property of circular dichroism (CD) is critical for these applications. Although the surface plasmon resonance (SPR) mode at a specific moment can explain the CD properties of chiral structures, to gain a better understanding of chirality, the mode shape of the SPR on a nanostructure must be analyzed throughout an entire period. Our study proposes an X-shaped nanostructure to investigate the temporal evolution of plasmon resonance in chiral structures. The simulation results demonstrated that our structure exhibited a significant temporal evolution in plasmonic oscillations, providing new insights into the nature of chirality. In addition, we provided a comprehensive theoretical explanation of CD using the Born–Kuhn model. Furthermore, we discovered that the CD in the X-shaped structure was intensified by the asymmetric interference between the structure and underlying gold film substrate.","PeriodicalId":16775,"journal":{"name":"Journal of Optics","volume":"57 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140608781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}