Optica最新文献

{"title":"Broadband near-ultraviolet dual comb spectroscopy","authors":"Lukas Fürst, Adrian Kirchner, Alexander Eber, Florian Siegrist, Robert di Vora, and Birgitta Bernhardt","doi":"10.1364/optica.516783","DOIUrl":"https://doi.org/10.1364/optica.516783","url":null,"abstract":"The highly energetic photons of ultraviolet light drive electronic and rovibronic transitions in all molecular species. This radiation is thus a prime tool for strongly selective spectroscopic fingerprinting and real-time environmental monitoring if broad spectral coverage, short acquisition times, and high spectral resolution are achieved–requirements that are in mutual competition in traditional applications. As an approach with intrinsic potency in all three aspects, here we introduce ultraviolet dual comb spectroscopy using two broadband ultraviolet frequency combs centered at 871 THz and covering a spectral bandwidth of 35.7 THz. Within a 100 µs acquisition time window, we obtain rotational state-resolved absorption spectra of formaldehyde, a prototype molecule with high relevance for laser spectroscopy and environmental sciences. To our knowledge, this is the first realization of broadband dual comb spectroscopy in the ultraviolet spectral region and a pioneering tool to allow for real-time monitoring of rovibronic transitions.","PeriodicalId":19515,"journal":{"name":"Optica","volume":"32 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140343325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"High-efficiency high-numerical-aperture metalens designed by maximizing the efficiency limit","authors":"Shiyu Li, Ho-Chun Lin, and Chia Wei Hsu","doi":"10.1364/optica.514907","DOIUrl":"https://doi.org/10.1364/optica.514907","url":null,"abstract":"Theoretical bounds are commonly used to assess the limitations of photonic design. Here we introduce a more active way to use theoretical bounds, integrating them into part of the design process and identifying optimal system parameters that maximize the efficiency limit itself. As an example, we consider wide-field-of-view high-numerical-aperture metalenses, which can be used for high-resolution imaging in microscopy and endoscopy, but no existing design has achieved a high efficiency. By choosing aperture sizes to maximize an efficiency bound, setting the thickness according to a thickness bound, and then performing inverse design, we come up with high-numerical-aperture (<span><span style=\"color: inherit;\"><span><span><span>N</span><span>A</span></span><span style=\"margin-left: 0.333em; margin-right: 0.333em;\">=</span><span><span>0.9</span></span></span></span><script type=\"math/tex\">{rm NA} = {0.9}</script></span>) metalens designs with, to our knowledge, record-high 98% transmission efficiency and 92% Strehl ratio across all incident angles within a 60° field of view, reaching the maximized bound. This maximizing-efficiency-limit approach applies to any multi-channel system and can help a wide range of optical devices reach their highest possible performance.","PeriodicalId":19515,"journal":{"name":"Optica","volume":"45 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2024-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140322032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Scalable machine learning-assisted clear-box characterization for optimally controlled photonic circuits","authors":"Andreas Fyrillas, Olivier Faure, Nicolas Maring, Jean Senellart, and Nadia Belabas","doi":"10.1364/optica.512148","DOIUrl":"https://doi.org/10.1364/optica.512148","url":null,"abstract":"Photonic integrated circuits offer a compact and stable platform for generating, manipulating, and detecting light. They are instrumental for classical and quantum applications. Imperfections stemming from fabrication constraints, tolerances, and operation wavelength impose limitations on the accuracy and thus utility of current photonic integrated devices. Mitigating these imperfections typically necessitates a model of the underlying physical structure and the estimation of parameters that are challenging to access. Direct solutions are currently lacking for mesh configurations extending beyond trivial cases. We introduce a scalable and innovative method to characterize photonic chips through an iterative machine learning-assisted procedure. Our method is based on a clear-box approach that harnesses a fully modeled virtual replica of the photonic chip to characterize. The process is sample-efficient and can be carried out with a continuous-wave laser and powermeters. The model estimates individual passive phases, crosstalk, beamsplitter reflectivity values, and relative input/output losses. Building upon the accurate characterization results, we mitigate imperfections to enable enhanced control over the device. We validate our characterization and imperfection mitigation methods on a 12-mode Clements-interferometer equipped with 126 phase shifters, achieving beyond state-of-the-art chip control with an average 99.77% amplitude fidelity on 100 implemented Haar-random unitary matrices.","PeriodicalId":19515,"journal":{"name":"Optica","volume":"34 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2024-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140164633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Sculpting harmonic comb states in terahertz quantum cascade lasers by controlled engineering","authors":"Elisa Riccardi, M. Alejandro Justo Guerrero, Valentino Pistore, Lukas Seitner, Christian Jirauschek, Lianhe Li, A. Giles Davies, Edmund H. Linfield, and Miriam S. Vitiello","doi":"10.1364/optica.509929","DOIUrl":"https://doi.org/10.1364/optica.509929","url":null,"abstract":"Optical frequency combs (OFCs), which establish a rigid phase-coherent link between the microwave and optical domains of the electromagnetic spectrum, are emerging as key high-precision tools for the development of quantum technology platforms. These include potential applications for communication, computation, information, sensing, and metrology and can extend from the near-infrared with micro-resonator combs, up to the technologically attractive terahertz (THz) frequency range, with powerful and miniaturized quantum cascade laser (QCL) FCs. The recently discovered ability of the QCLs to produce a harmonic frequency comb (HFC)—a FC with large intermodal spacings—has attracted new interest in these devices for both applications and fundamental physics, particularly for the generation of THz tones of high spectral purity for high data rate wireless communication networks, for radio frequency arbitrary waveform synthesis, and for the development of quantum key distributions. The controlled generation of harmonic states of a specific order remains, however, elusive in THz QCLs. Here, and by design, we devise a strategy to obtain broadband HFC emission of a pre-defined order in a QCL. By patterning <span><span>n</span><script type=\"math/tex\">n</script></span> regularly spaced defects on the top surface of a double-metal Fabry–Perot QCL, we demonstrate harmonic comb emission with modes spaced by an (<span><span>n + 1</span><script type=\"math/tex\">n + 1</script></span>) free spectral range and with an optical power/mode of <span><span>{sim}{270};unicode{x00B5} {rm W}</span><script type=\"math/tex\">{sim}{270};unicode{x00B5} {rm W}</script></span>.","PeriodicalId":19515,"journal":{"name":"Optica","volume":"17 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140164591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"High-resolution ptychographic imaging at a seeded free-electron laser source using OAM beams","authors":"Matteo Pancaldi, Francesco Guzzi, Charles S. Bevis, Michele Manfredda, Jonathan Barolak, Stefano Bonetti, Iuliia Bykova, Dario De Angelis, Giovanni De Ninno, Mauro Fanciulli, Luka Novinec, Emanuele Pedersoli, Arun Ravindran, Benedikt Rösner, Christian David, Thierry Ruchon, Alberto Simoncig, Marco Zangrando, Daniel E. Adams, Paolo Vavassori, Maurizio Sacchi, George Kourousias, Giulia F. Mancini, and Flavio Capotondi","doi":"10.1364/optica.509745","DOIUrl":"https://doi.org/10.1364/optica.509745","url":null,"abstract":"Electromagnetic waves possessing orbital angular momentum (OAM) are powerful tools for applications in optical communications, quantum technologies, and optical tweezers. Recently, they have attracted growing interest since they can be harnessed to detect peculiar helical dichroic effects in chiral molecular media and in magnetic nanostructures. In this work, we perform single-shot per position ptychography on a nanostructured object at a seeded free-electron laser, using extreme ultraviolet OAM beams of different topological charge orders <span><span style=\"color: inherit;\"><span><span>ℓ</span></span></span><script type=\"math/tex\">ell</script></span> generated with spiral zone plates. By controlling <span><span style=\"color: inherit;\"><span><span>ℓ</span></span></span><script type=\"math/tex\">ell</script></span>, we demonstrate how the structural features of OAM beam profiles determine an improvement of about 30% in image resolution with respect to conventional Gaussian beam illumination. This result extends the capabilities of coherent diffraction imaging techniques, and paves the way for achieving time-resolved high-resolution (below 100 nm) microscopy on large area samples.","PeriodicalId":19515,"journal":{"name":"Optica","volume":"22 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140161809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Self-injection-locked optical parametric oscillator based on microcombs","authors":"Fuchuan Lei, Yi Sun, Óskar B. Helgason, Zhichao Ye, Yan Gao, Magnus Karlsson, Peter A. Andrekson, and Victor Torres-Company","doi":"10.1364/optica.509239","DOIUrl":"https://doi.org/10.1364/optica.509239","url":null,"abstract":"Narrow-linewidth yet tunable laser oscillators are one of the most important tools for precision metrology, optical atomic clocks, sensing, and quantum computing. Commonly used tunable coherent oscillators are based on stimulated emission or stimulated Brillouin scattering; as a result, the operating wavelength band is limited by the gain media. Based on nonlinear optical gain, optical parametric oscillators (OPOs) enable coherent signal generation within the whole transparency window of the medium used. However, the demonstration of OPO-based Hertz-level linewidth and tunable oscillators has remained elusive. Here, we present a tunable coherent oscillator based on a multimode coherent OPO in a high-Q microresonator, i.e., a microcomb. Single-mode coherent oscillation is realized through self-injection locking (SIL) of one selected comb line. We achieve coarse tuning up to 20 nm and an intrinsic linewidth down to sub-Hertz level, which is three orders of magnitude lower than the pump. Furthermore, we demonstrate that this scheme results in the repetition rate stabilization of the microcomb. These results open exciting possibilities for generating tunable coherent radiation where stimulated emission materials are difficult to obtain, and the stabilization of microcomb sources beyond the limits imposed by the thermorefractive noise in the cavity.","PeriodicalId":19515,"journal":{"name":"Optica","volume":"76 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140161869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Miniaturized computational spectrometer based on two-photon absorption","authors":"Yaotian Zhao, Xuhan Guo, Jinlong Xiang, Zhenyu Zhao, Yujia Zhang, Xi Xiao, Jia Liu, Daigao Chen, and Yikai Su","doi":"10.1364/optica.511658","DOIUrl":"https://doi.org/10.1364/optica.511658","url":null,"abstract":"On-chip spectrometers hold significant promise in the development of laboratory-on-a-chip applications. However, the spectrometers usually require extra on-chip or off-chip photodetectors (PDs) to sense optical signals, resulting in increased footprints and costs. In this paper, we address this issue by proposing a fully on-chip spectrometer based on two-photon absorption (TPA) in a simple micro-ring resonator (MRR) configuration. While TPA is a commonly undesired phenomenon in conventional silicon devices due to its attached absorption losses and nonlinearity, we exploit it as a powerful and efficient tool for encoding spectral information, instead of using additional PDs. The input spectrum can be reconstructed from the sensed TPA current. Our proposed spectrometer achieves a bandwidth of 10 nm with a resolution of 0.4 nm while occupying a small footprint of only <span><span>{16} times {16};unicode{x00B5}{rm m}^2</span><script type=\"math/tex\">{16} times {16};unicode{x00B5}{rm m}^2</script></span>, and the bandwidth can be further improved through several cascaded MRRs. This advancement could enable forward fully integrated and miniaturized spectrometers with low cost, which holds far-reaching applications in <i>in situ</i> biochemical analysis, remote sensing, and intelligent healthcare.","PeriodicalId":19515,"journal":{"name":"Optica","volume":"23 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140139459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Low-power, agile electro-optic frequency comb spectrometer for integrated sensors","authors":"Kyunghun Han, David A. Long, Sean M. Bresler, Junyeob Song, Yiliang Bao, Benjamin J. Reschovsky, Kartik Srinivasan, Jason J. Gorman, Vladimir A. Aksyuk, and Thomas W. LeBrun","doi":"10.1364/optica.506108","DOIUrl":"https://doi.org/10.1364/optica.506108","url":null,"abstract":"Sensing platforms based upon photonic integrated circuits have shown considerable promise; however, they require corresponding advancements in integrated optical readout technologies. Here, we present an on-chip spectrometer that leverages an integrated thin-film lithium niobate modulator to produce a frequency-agile electro-optic frequency comb for interrogating chip-scale temperature and acceleration sensors. The chirped comb process allows for ultralow radiofrequency drive voltages, which are as much as seven orders of magnitude less than the lowest found in the literature and are generated using a chip-scale, microcontroller-driven direct digital synthesizer. The on-chip comb spectrometer is able to simultaneously interrogate both an on-chip temperature sensor and an off-chip, microfabricated optomechanical accelerometer with cutting-edge sensitivities of <span><span style=\"color: inherit;\"><span><span style=\"margin-left: 0.333em; margin-right: 0.333em;\">≈</span><span style=\"margin-left: -0.167em; width: 0em; height: 0em;\"></span><span><span>5</span></span><span style=\"width: 0.278em; height: 0em;\"></span><span>µ</span><span><span>K</span></span><span style=\"margin-left: 0.267em; margin-right: 0.267em;\">⋅</span><span><span><span style=\"margin-right: 0.05em;\"><span>H</span><span>z</span></span><span style=\"vertical-align: 0.5em;\"><span>−</span><span>1</span><span><span>/</span></span><span>2</span></span></span></span></span></span><script type=\"math/tex\">approx !{5};unicode{x00B5} {rm K} cdot {{rm Hz}^{- 1/2}}</script></span> and <span><span style=\"color: inherit;\"><span><span style=\"margin-left: 0.333em; margin-right: 0.333em;\">≈</span><span style=\"margin-left: -0.167em; width: 0em; height: 0em;\"></span><span><span>130</span></span><span style=\"width: 0.278em; height: 0em;\"></span><span>µ</span><span><span>m</span></span><span style=\"margin-left: 0.267em; margin-right: 0.267em;\">⋅</span><span><span><span style=\"margin-right: 0.05em;\"><span>s</span></span><span style=\"vertical-align: 0.5em;\"><span>−</span><span>2</span></span></span></span><span style=\"margin-left: 0.267em; margin-right: 0.267em;\">⋅</span><span><span><span style=\"margin-right: 0.05em;\"><span>H</span><span>z</span></span><span style=\"vertical-align: 0.5em;\"><span>−</span><span>1</span><span><span>/</span></span><span>2</span></span></span></span></span></span><script type=\"math/tex\">approx !{130};unicode{x00B5}{rm m} cdot {{rm s}^{- 2}} cdot {{rm Hz}^{- 1/2}}</script></span>, respectively. This platform is compatible with a broad range of existing photonic integrated circuit technologies, where its combination of frequency agility and ultralow radiofrequency power requirements are expected to have applications in fields such as quantum science and optical computing.","PeriodicalId":19515,"journal":{"name":"Optica","volume":"115 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140104617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Overcoming the diffraction limit by exploiting unmeasured scattering media","authors":"Shuai Sun, Zhen-Wu Nie, Long-Kun Du, Chen Chang, and Wei-Tao Liu","doi":"10.1364/optica.507310","DOIUrl":"https://doi.org/10.1364/optica.507310","url":null,"abstract":"Scattering is not necessarily an obstacle to imaging. It can help enhance imaging performance beyond the reach of a lens system. However, current scattering-enhanced imaging systems require prior knowledge of the transmission matrix. There are also some techniques that do not require such prior knowledge to see through strongly scattering media, but the results are still limited by the optics used. Here we propose overcoming the diffraction limit through a visually opaque diffuser. By controlling the distance between the diffuser and lens system, light with higher spatial frequencies is scattered into the entrance pupil. With the deformed wavefront corrected, we experimentally achieved imaging with <span><span>3.39 times</span><script type=\"math/tex\">3.39 times</script></span> enhancement of the Rayleigh limit. In addition, our method works well for objects that are <span><span>4 times</span><script type=\"math/tex\">4 times</script></span> larger than the memory effect range and can maintain super-resolution performance for a depth of field <span><span>6.6 times</span><script type=\"math/tex\">6.6 times</script></span> larger than a lens can achieve. Using our method, an obstructive scattering medium can enhance the throughput of the imaging system, even though the transmission matrix of the scattering medium has not been measured beforehand.","PeriodicalId":19515,"journal":{"name":"Optica","volume":"40 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140067605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Quartz as an accurate high-field low-cost THz helicity detector","authors":"Maximilian Frenzel, Joanna M. Urban, Leona Nest, Tobias Kampfrath, Michael S. Spencer, and Sebastian F. Maehrlein","doi":"10.1364/optica.515909","DOIUrl":"https://doi.org/10.1364/optica.515909","url":null,"abstract":"Emerging concepts employing angular momentum of THz light for ultrafast material control rely on the measurement of undistorted intense THz fields and on the precise knowledge about sophisticated THz helicity states. Here, we establish z-cut <span><span style=\"color: inherit;\"><span><span>α</span></span></span><script type=\"math/tex\">alpha</script></span>-quartz as a precise electro-optic THz detector for full amplitude, phase, and polarization measurement of highly intense THz fields, all at a fraction of costs of conventional THz detectors. We experimentally determine its detector response function, in excellent agreement with our modeling. Thereupon, we develop a swift and reliable protocol to precisely measure arbitrary THz polarization and helicity states. This two-dimensional electro-optic sampling in <span><span style=\"color: inherit;\"><span><span>α</span></span></span><script type=\"math/tex\">alpha</script></span>-quartz fosters rapid and cost-efficient THz time-domain ellipsometry and enables the characterization of polarization-tailored fields for driving chiral or other helicity-sensitive quasi-particles and topologies.","PeriodicalId":19515,"journal":{"name":"Optica","volume":"62 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140067777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}