Nature Photonics最新文献

{"title":"Observation of loss-enhanced magneto-optical effect","authors":"Ya-Ping Ruan, Jiang-Shan Tang, Zhipeng Li, Haodong Wu, Wenpeng Zhou, Longqi Xiao, Jianfeng Chen, Shi-Jun Ge, Wei Hu, Han Zhang, Cheng-Wei Qiu, Wuming Liu, Hui Jing, Yan-Qing Lu, Keyu Xia","doi":"10.1038/s41566-024-01592-y","DOIUrl":"https://doi.org/10.1038/s41566-024-01592-y","url":null,"abstract":"<p>Magneto-optical (MO) effects have a pivotal role in modern photonic devices for light manipulation and sensing, but the study of these effects has so far been limited to the MO Faraday and Kerr effects. Conventional MO systems encounter considerable intrinsic losses, markedly hampering their ability to amplify the MO effects. Here we introduce a loss-enhanced MO effect to sublinearly amplify the frequency response of a non-Hermitian optical cavity under different background magnetic fields. This exceptional MO effect relies on an architecture of MO material embedded in a Fabry–Pérot cavity, accompanied by a polarization-dependent optical absorption, that is, linear dichroism, to construct a reconfigurable exceptional point. The experimental results show that two eigenmodes of the Fabry–Pérot cavity exhibit sublinear frequency splitting. By electrically reconfiguring the absorber, the eigenfrequency shift can be adaptively enhanced under different background magnetic fields. Using this effect, we demonstrate the detection of subtle magnetic field variations in a strong background, with the system’s response magnified by a factor exceeding 10 and sensitivity increased threefold compared with its conventional Hermitian counterpart. Our study leverages exceptional physics to study the MO effect and develops a new class of reconfigurable MO devices equipped with enhanced sensitivity for potential integration with photonic systems.</p>","PeriodicalId":18926,"journal":{"name":"Nature Photonics","volume":"23 1","pages":""},"PeriodicalIF":35.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142848982","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":"Ultrabright molecular scintillators enabled by lanthanide-assisted near-unity triplet exciton recycling","authors":"Jiahui Xu, Rui Luo, Zichao Luo, Jun Xu, Zhen Mu, Hongyu Bian, Siew Yin Chan, Benjamin Yue Hao Tan, Dongzhi Chi, Zhongfu An, Guichuan Xing, Xian Qin, Changyang Gong, Yiming Wu, Xiaogang Liu","doi":"10.1038/s41566-024-01586-w","DOIUrl":"https://doi.org/10.1038/s41566-024-01586-w","url":null,"abstract":"<p>The secondary X-rays generated by the interaction of high-energy particles with scintillators can be converted into lower-energy excitons through thermalization, emitting light in the process. Capturing these secondary X-ray quanta efficiently is key to enhancing scintillation performance and boosting radiation detector sensitivity. Here we report a molecular design strategy using organic ligands to reclaim energy lost during the relaxation of secondary X-rays. This approach results in an enhancement in radioluminescence within lanthanide metal complexes by more than three orders of magnitude. By controlling the triplet energy of these ligands, we enable lanthanide centres to capture dark triplet excitons with near-unity extraction efficiency. These excitons arise from the absorption of secondary X-rays and transferred to the lanthanide centres through resonance energy transfer. This process delivers radioluminescence with orders of magnitude higher efficiency than existing organic or commercial inorganic scintillators. Tailoring metal centres and their coordination environments allows these organolanthanide scintillators to tune their spectra from ultraviolet to near-infrared, with lifetimes adjustable from tens of nanoseconds to hundreds of microseconds. These molecular scintillators enable high-resolution radiographic imaging and X-ray-mediated photodynamic therapy. Our findings not only unravel the link between scintillation performance and triplet exciton recycling but also lay the foundation for designing highly efficient organic scintillators that could revolutionize various fields.</p>","PeriodicalId":18926,"journal":{"name":"Nature Photonics","volume":"30 1","pages":""},"PeriodicalIF":35.0,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142815691","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":"Tunnelling escape of waves","authors":"David A. B. Miller, Zeyu Kuang, Owen D. Miller","doi":"10.1038/s41566-024-01578-w","DOIUrl":"https://doi.org/10.1038/s41566-024-01578-w","url":null,"abstract":"<p>Applications of waves in communications, information processing and sensing need a clear understanding of how many strongly coupled channels or degrees of freedom exist in and out of volumes of space and how the coupling falls off for larger numbers. Numerical results are possible, and some heuristics exist, but there has been no simple physical picture and explanation for arbitrary volumes. By considering waves from a bounding spherical volume, we show a clear onset of a tunnelling escape of waves that both defines a limiting number of well-coupled channels for any volume and explains the subsequent rapid fall-off of coupling strengths. The approach works over all size scales, from nanophotonics and small radiofrequency antennas up to imaging optics. It gives a unified view from the multipole expansions common for antennas and small objects to the limiting plane and evanescent waves of large optics, showing that all such waves can escape to propagation to some degree, by tunnelling if necessary, and gives a precise diffraction limit.</p>","PeriodicalId":18926,"journal":{"name":"Nature Photonics","volume":"8 1","pages":""},"PeriodicalIF":35.0,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760353","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":"Single-chip photonic deep neural network with forward-only training","authors":"Saumil Bandyopadhyay,&nbsp;Alexander Sludds,&nbsp;Stefan Krastanov,&nbsp;Ryan Hamerly,&nbsp;Nicholas Harris,&nbsp;Darius Bunandar,&nbsp;Matthew Streshinsky,&nbsp;Michael Hochberg,&nbsp;Dirk Englund","doi":"10.1038/s41566-024-01567-z","DOIUrl":"10.1038/s41566-024-01567-z","url":null,"abstract":"As deep neural networks revolutionize machine learning, energy consumption and throughput are emerging as fundamental limitations of complementary metal–oxide–semiconductor (CMOS) electronics. This has motivated a search for new hardware architectures optimized for artificial intelligence, such as electronic systolic arrays, memristor crossbar arrays and optical accelerators. Optical systems can perform linear matrix operations at an exceptionally high rate and efficiency, motivating recent demonstrations of low-latency matrix accelerators and optoelectronic image classifiers. However, demonstrating coherent, ultralow-latency optical processing of deep neural networks has remained an outstanding challenge. Here we realize such a system in a scalable photonic integrated circuit that monolithically integrates multiple coherent optical processor units for matrix algebra and nonlinear activation functions into a single chip. We experimentally demonstrate this fully integrated coherent optical neural network architecture for a deep neural network with six neurons and three layers that optically computes both linear and nonlinear functions with a latency of 410 ps, unlocking new applications that require ultrafast, direct processing of optical signals. We implement backpropagation-free in situ training on this system, achieving 92.5% accuracy on a six-class vowel classification task, which is comparable to the accuracy obtained on a digital computer. This work lends experimental evidence to theoretical proposals for in situ training, enabling orders of magnitude improvements in the throughput of training data. Moreover, the fully integrated coherent optical neural network opens the path to inference at nanosecond latency and femtojoule per operation energy efficiency. Researchers experimentally demonstrate a fully integrated coherent optical neural network. The system, with six neurons and three layers, operates with a latency of 410 ps.","PeriodicalId":18926,"journal":{"name":"Nature Photonics","volume":"18 12","pages":"1335-1343"},"PeriodicalIF":32.3,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760380","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":"Ultra-low-noise terahertz sources","authors":"Thomas Schneider","doi":"10.1038/s41566-024-01583-z","DOIUrl":"10.1038/s41566-024-01583-z","url":null,"abstract":"Oscillators for tunable terahertz waves with ultra-high spectral purity may pave the way for precise molecular clocks and extremely high-data-rate wireless communications.","PeriodicalId":18926,"journal":{"name":"Nature Photonics","volume":"18 12","pages":"1230-1231"},"PeriodicalIF":32.3,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760357","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":"Optical computing and artificial intelligence","authors":"David Pile","doi":"10.1038/s41566-024-01582-0","DOIUrl":"10.1038/s41566-024-01582-0","url":null,"abstract":"Light-based processing and machine learning featured heavily in San Diego at the 2024 SPIE Optics + Photonics conference. Enthusiasm was coupled with questions related to the real-world applicability and the merits of linear vs non-linear, and all-optical vs hybrid, approaches.","PeriodicalId":18926,"journal":{"name":"Nature Photonics","volume":"18 12","pages":"1240-1242"},"PeriodicalIF":32.3,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760456","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":"Attosecond X-ray laser vision","authors":"Diling Zhu,&nbsp;David A. Reis","doi":"10.1038/s41566-024-01575-z","DOIUrl":"10.1038/s41566-024-01575-z","url":null,"abstract":"","PeriodicalId":18926,"journal":{"name":"Nature Photonics","volume":"18 12","pages":"1232-1233"},"PeriodicalIF":32.3,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760457","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":"Terahertz matters","authors":"Noriaki Horiuchi","doi":"10.1038/s41566-024-01581-1","DOIUrl":"10.1038/s41566-024-01581-1","url":null,"abstract":"Daniel Mittleman spoke with Nature Photonics about promising applications using terahertz waves, including spectroscopy, imaging, wireless communications, and quality control in industry.","PeriodicalId":18926,"journal":{"name":"Nature Photonics","volume":"18 12","pages":"1226-1227"},"PeriodicalIF":32.3,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760458","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":"Switching it up","authors":"Gert-Jan A. H. Wetzelaer","doi":"10.1038/s41566-024-01569-x","DOIUrl":"10.1038/s41566-024-01569-x","url":null,"abstract":"Light upconversion and bistable optical switching is achieved via positive photonic feedback by integrating a photoactive layer with a tandem OLED.","PeriodicalId":18926,"journal":{"name":"Nature Photonics","volume":"18 12","pages":"1238-1239"},"PeriodicalIF":32.3,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760355","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":"Scrutinizing liquid molecules","authors":"Mohammed Th. Hassan","doi":"10.1038/s41566-024-01572-2","DOIUrl":"10.1038/s41566-024-01572-2","url":null,"abstract":"A new attosecond metrology technique for studying light–molecule interactions in liquids may open the door for variety of attosecond applications in chemistry and biology.","PeriodicalId":18926,"journal":{"name":"Nature Photonics","volume":"18 12","pages":"1234-1235"},"PeriodicalIF":32.3,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142760555","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}