{"title":"Giant enhancement of nonlinear harmonics of an optical-tweezer phonon laser","authors":"Guangzong Xiao, Tengfang Kuang, Yutong He, Xinlin Chen, Wei Xiong, Xiang Han, Zhongqi Tan, Hui Luo, Hui Jing","doi":"10.1186/s43593-024-00064-8","DOIUrl":"https://doi.org/10.1186/s43593-024-00064-8","url":null,"abstract":"<p>Phonon lasers, as mechanical analogues of optical lasers, are unique tools for not only fundamental studies of the emerging field of phononics but also diverse applications such as deep-ocean monitoring, force sensing, and biomedical ultrasonics. Recently, nonlinear phonon-lasing effects were observed in an opto-levitated micro-sphere, i.e., the spontaneous emerging of weak signals of high-order phonon harmonics in the phonon lasing regime. However, both the strengths and the quality factors of the emerging phonon harmonics are very poor, thus severely hindering their potential applications in making and utilizing nonlinear phonon-laser devices. Here we show that, by applying a single-colour electronic injection to this levitated system, giant enhancement can be achieved for all higher-order phonon harmonics, with more than 3 orders enhanced brightness and 5 orders narrowed linewidth. Such an electronically-enhanced phonon laser is also far more stable, with frequency stability extended from a dozen of minutes to over 1 h. More importantly, higher-order phonon correlations, as an essential lasing feature, are confirmed to be enhanced by the electronic injection as well, which as far as we know, has not been reported in previous works using this technique. This work, providing much stronger and better-quality signals of coherent phonon harmonics, is a key step towards controlling and utilizing nonlinear phonon lasers for applications such as phonon frequency combs, broadband phonon sensors, and ultrasonic bio-medical diagnosis.</p>","PeriodicalId":72891,"journal":{"name":"eLight","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Polarization-entangled photon-pair source with van der Waals 3R-WS2 crystal","authors":"Jiangang Feng, Yun-Kun Wu, Ruihuan Duan, Jun Wang, Weijin Chen, Jiazhang Qin, Zheng Liu, Guang-Can Guo, Xi-Feng Ren, Cheng-Wei Qiu","doi":"10.1186/s43593-024-00074-6","DOIUrl":"https://doi.org/10.1186/s43593-024-00074-6","url":null,"abstract":"<p>Ultracompact entangled photon sources are pivotal to miniaturized quantum photonic devices. Van der Waals (vdW) nonlinear crystals promise efficient photon-pair generation and on-chip monolithic integration with nanophotonic circuitry. However, it remains challenging to generate maximally entangled Bell states of photon pairs with high purity, generation rate, and fidelity required for practical applications. Here, we realize a polarization-entangled photon-pair source based on spontaneous parametric down conversion in an ultrathin rhombohedral tungsten disulfide (3R-WS<sub>2</sub>) crystal. This vdW entangled photonic source exhibits a high photon-pair purity with a coincidence-to-accidental ratio of above 800, a generation rate of 31 Hz, and two maximally polarization-entangled Bell states with fidelities exceeding 0.93 and entanglement degree over 0.97. These results stem from scalable optical nonlinearity, enhanced second-order susceptibility by electronic transitions, and a well-defined symmetry-enabled selection rule inherent in 3R-WS<sub>2</sub>. Our polarization entangled photon source can be integrated with photonic structures for generating more complex entangled states, thus paving an avenue for advanced quantum photonic systems toward computation and metrology.</p>","PeriodicalId":72891,"journal":{"name":"eLight","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
eLightPub Date : 2024-08-16DOI: 10.1186/s43593-024-00070-w
Jacob Khurgin, Anton Yu. Bykov, Anatoly V. Zayats
{"title":"Hot-electron dynamics in plasmonic nanostructures: fundamentals, applications and overlooked aspects","authors":"Jacob Khurgin, Anton Yu. Bykov, Anatoly V. Zayats","doi":"10.1186/s43593-024-00070-w","DOIUrl":"https://doi.org/10.1186/s43593-024-00070-w","url":null,"abstract":"<p>Light absorption near a surface of conductive materials and nanostructures leads to the excitation of nonequilibrium, high-energy charge carriers: electrons above the Fermi level or holes below it. When remaining inside a material, these so-called hot carriers result in nonlinear, Kerr-type, optical effects important for controlling light with light. They can also transfer into the surroundings of the nanostructures, resulting in photocurrent, or they can interact with adjacent molecules and media, inducing photochemical transformations. Understanding the dynamics of hot carriers and related effects in plasmonic nanostructures is important for the development of ultrafast detectors and nonlinear optical components, broadband photocatalysis, enhanced nanoscale optoelectronic devices, nanoscale and ultrafast temperature control, and other technologies of tomorrow. In this review, we will discuss the fundamentals of plasmonically-engendered hot electrons, focusing on the overlooked aspects, theoretical descriptions and experimental methods to study them, and describe prototypical processes and examples of most promising applications of hot-electron processes at the metal interfaces.</p>","PeriodicalId":72891,"journal":{"name":"eLight","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multi-resolution analysis enables fidelity-ensured deconvolution for fluorescence microscopy","authors":"Yiwei Hou, Wenyi Wang, Yunzhe Fu, Xichuan Ge, Meiqi Li, Peng Xi","doi":"10.1186/s43593-024-00073-7","DOIUrl":"https://doi.org/10.1186/s43593-024-00073-7","url":null,"abstract":"<p>Fluorescence microscopic imaging is essentially a convolution process distorted by random noise, limiting critical parameters such as imaging speed, duration, and resolution. Though algorithmic compensation has shown great potential to enhance these pivotal aspects, its fidelity remains questioned. Here we develop a physics-rooted computational resolution extension and denoising method with ensured fidelity. Our approach employs a multi-resolution analysis (MRA) framework to extract the two main characteristics of fluorescence images against noise: across-edge contrast, and along-edge continuity. By constraining the two features in a model-solution framework using framelet and curvelet, we develop MRA deconvolution algorithms, which improve the signal-to-noise ratio (SNR) up to 10 dB higher than spatial derivative based penalties, and can provide up to two-fold fidelity-ensured resolution improvement rather than the artifact-prone Richardson-Lucy inference. We demonstrate our methods can improve the performance of various diffraction-limited and super-resolution microscopies with ensured fidelity, enabling accomplishments of more challenging imaging tasks.</p>","PeriodicalId":72891,"journal":{"name":"eLight","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141937710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
eLightPub Date : 2024-07-24DOI: 10.1186/s43593-024-00072-8
Michele B. Rota, Tobias M. Krieger, Quirin Buchinger, Mattia Beccaceci, Julia Neuwirth, Hêlio Huet, Nikola Horová, Gabriele Lovicu, Giuseppe Ronco, Saimon F. Covre da Silva, Giorgio Pettinari, Magdalena Moczała-Dusanowska, Christoph Kohlberger, Santanu Manna, Sandra Stroj, Julia Freund, Xueyong Yuan, Christian Schneider, Miroslav Ježek, Sven Höfling, Francesco Basso Basset, Tobias Huber-Loyola, Armando Rastelli, Rinaldo Trotta
{"title":"A source of entangled photons based on a cavity-enhanced and strain-tuned GaAs quantum dot","authors":"Michele B. Rota, Tobias M. Krieger, Quirin Buchinger, Mattia Beccaceci, Julia Neuwirth, Hêlio Huet, Nikola Horová, Gabriele Lovicu, Giuseppe Ronco, Saimon F. Covre da Silva, Giorgio Pettinari, Magdalena Moczała-Dusanowska, Christoph Kohlberger, Santanu Manna, Sandra Stroj, Julia Freund, Xueyong Yuan, Christian Schneider, Miroslav Ježek, Sven Höfling, Francesco Basso Basset, Tobias Huber-Loyola, Armando Rastelli, Rinaldo Trotta","doi":"10.1186/s43593-024-00072-8","DOIUrl":"https://doi.org/10.1186/s43593-024-00072-8","url":null,"abstract":"A quantum-light source that delivers photons with a high brightness and a high degree of entanglement is fundamental for the development of efficient entanglement-based quantum-key distribution systems. Among all possible candidates, epitaxial quantum dots are currently emerging as one of the brightest sources of highly entangled photons. However, the optimization of both brightness and entanglement currently requires different technologies that are difficult to combine in a scalable manner. In this work, we overcome this challenge by developing a novel device consisting of a quantum dot embedded in a circular Bragg resonator, in turn, integrated onto a micromachined piezoelectric actuator. The resonator engineers the light-matter interaction to empower extraction efficiencies up to 0.69(4). Simultaneously, the actuator manipulates strain fields that tune the quantum dot for the generation of entangled photons with corrected fidelities to a maximally entangled state up to 0.96(1). This hybrid technology has the potential to overcome the limitations of the key rates that plague QD-based entangled sources for entanglement-based quantum key distribution and entanglement-based quantum networks.","PeriodicalId":72891,"journal":{"name":"eLight","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141782286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
eLightPub Date : 2024-07-12DOI: 10.1186/s43593-024-00068-4
Wenpeng Zhou, Ya-Ping Ruan, Haodong Wu, Han Zhang, Jiang-Shan Tang, Zhenda Xie, Lei Tang, Yu Wang, Yue-E Ji, Kunpeng Jia, Cheng-Wei Qiu, Yan-Qing Lu, Keyu Xia
{"title":"Magnetic-free chiral eigenmode spectroscopy for simultaneous sensitive measurement of optical rotary dispersion and circular dichroism","authors":"Wenpeng Zhou, Ya-Ping Ruan, Haodong Wu, Han Zhang, Jiang-Shan Tang, Zhenda Xie, Lei Tang, Yu Wang, Yue-E Ji, Kunpeng Jia, Cheng-Wei Qiu, Yan-Qing Lu, Keyu Xia","doi":"10.1186/s43593-024-00068-4","DOIUrl":"https://doi.org/10.1186/s43593-024-00068-4","url":null,"abstract":"<p>Chirality, defined by Lord Kelvin, refers to the geometric symmetry property of an object that cannot be superposed onto its mirror image using rotations and translations. The material’s chirality can be probed with light as the optical activity: optical rotary dispersion (ORD) and circular dichroism (CD). It is still challenging to yield extremely sensitive ORD and CD for very weak chirality and measure both simultaneously. Cavity ringdown polarimetry has been reported to improve ORD detection sensitivity with the absence of equally important CD signature, at the price of high cavity finesse near 400, frequency-locking sophistication, and large magnetic field. Here, we report a unique recipe to demonstrate the simultaneous measurement of ORD and the CD by separately observing the chiral eigenmode spectra from a bowtie optical cavity with a finesse about 30, without resorting to frequency locking or magnetic field. We obtain a sensitivity of <span>(sim 2.7times 10^{-3} text {deg}/sqrt{text {Hz}})</span> for ORD, <span>(sim 8.1 times 10^{-6} /sqrt{text {Hz}})</span> for CD, and a spectral resolution of <span>(0.04~text {pm})</span> within a millisecond-scale measurement. We present a cost-effective yet ultrasensitive account for chiral chromatography, the conformational dynamics and chiroptical analysis of biological samples which particularly exhibit weak and narrow spectral signals.</p>","PeriodicalId":72891,"journal":{"name":"eLight","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141609400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
eLightPub Date : 2024-07-08DOI: 10.1186/s43593-024-00069-3
Shunjia Wang, Wentao Qin, Tongyang Guan, Jingyu Liu, Qingnan Cai, Sheng Zhang, Lei Zhou, Yan Zhang, Yizheng Wu, Zhensheng Tao
{"title":"Flexible generation of structured terahertz fields via programmable exchange-biased spintronic emitters","authors":"Shunjia Wang, Wentao Qin, Tongyang Guan, Jingyu Liu, Qingnan Cai, Sheng Zhang, Lei Zhou, Yan Zhang, Yizheng Wu, Zhensheng Tao","doi":"10.1186/s43593-024-00069-3","DOIUrl":"https://doi.org/10.1186/s43593-024-00069-3","url":null,"abstract":"<p>Structured light, particularly in the terahertz frequency range, holds considerable potential for a diverse range of applications. However, the generation and control of structured terahertz radiation pose major challenges. In this work, we demonstrate a novel programmable spintronic emitter that can flexibly generate a variety of structured terahertz waves. This is achieved through the precise and high-resolution programming of the magnetization pattern on the emitter’s surface, utilizing laser-assisted local field cooling of an exchange-biased ferromagnetic heterostructure. Moreover, we outline a generic design strategy for realizing specific complex structured terahertz fields in the far field. Our device successfully demonstrates the generation of terahertz waves with diverse structured polarization states, including spatially separated circular polarizations, azimuthal or radial polarization states, and a full Poincaré beam. This innovation opens a new avenue for designing and generating structured terahertz radiations, with potential applications in terahertz microscopy, communication, quantum information, and light-matter interactions.</p>","PeriodicalId":72891,"journal":{"name":"eLight","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141571832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
eLightPub Date : 2024-06-29DOI: 10.1186/s43593-024-00066-6
Haoqi Zhao, Yichi Zhang, Zihe Gao, Jieun Yim, Shuang Wu, Natalia M. Litchinitser, Li Ge, Liang Feng
{"title":"Integrated preparation and manipulation of high-dimensional flying structured photons","authors":"Haoqi Zhao, Yichi Zhang, Zihe Gao, Jieun Yim, Shuang Wu, Natalia M. Litchinitser, Li Ge, Liang Feng","doi":"10.1186/s43593-024-00066-6","DOIUrl":"https://doi.org/10.1186/s43593-024-00066-6","url":null,"abstract":"<p>The hope for a futuristic global quantum internet that provides robust and high-capacity quantum information transfer lies largely on qudits, the fundamental quantum information carriers prepared in high-dimensional superposition states. However, preparing and manipulating N-dimensional flying qudits as well as subsequently establishing their entanglement are still challenging tasks, which require precise and simultaneous maneuver of 2 (N-1) parameters across multiple degrees of freedom. Here, using an integrated approach, we explore the synergy from two degrees of freedom of light, spatial mode and polarization, to generate, encode, and manipulate flying structured photons and their formed qudits in a four-dimensional Hilbert space with high quantum fidelity, intrinsically enabling enhanced noise resilience and higher quantum data rates. The four eigen spin–orbit modes of our qudits possess identical spatial–temporal characteristics in terms of intensity distribution and group velocity, thereby preserving long-haul coherence within the entirety of the quantum data transmission link. Judiciously leveraging the bi-photon entanglement, which is well preserved in the integrated manipulation process, we present versatile spin–orbit cluster states in an extensive dimensional Hilbert space. Such cluster states hold the promise for quantum error correction which can further bolster the channel robustness in long-range quantum communication.</p>","PeriodicalId":72891,"journal":{"name":"eLight","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141504826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Subwavelength imaging using a solid-immersion diffractive optical processor","authors":"Jingtian Hu, Kun Liao, Niyazi Ulas Dinç, Carlo Gigli, Bijie Bai, Tianyi Gan, Xurong Li, Hanlong Chen, Xilin Yang, Yuhang Li, Çağatay Işıl, Md Sadman Sakib Rahman, Jingxi Li, Xiaoyong Hu, Mona Jarrahi, Demetri Psaltis, Aydogan Ozcan","doi":"10.1186/s43593-024-00067-5","DOIUrl":"https://doi.org/10.1186/s43593-024-00067-5","url":null,"abstract":"<p>Phase imaging is widely used in biomedical imaging, sensing, and material characterization, among other fields. However, direct imaging of phase objects with subwavelength resolution remains a challenge. Here, we demonstrate subwavelength imaging of phase and amplitude objects based on all-optical diffractive encoding and decoding. To resolve subwavelength features of an object, the diffractive imager uses a thin, high-index solid-immersion layer to transmit high-frequency information of the object to a spatially-optimized diffractive encoder, which converts/encodes high-frequency information of the input into low-frequency spatial modes for transmission through air. The subsequent diffractive decoder layers (in air) are jointly designed with the encoder using deep-learning-based optimization, and communicate with the encoder layer to create magnified images of input objects at its output, revealing subwavelength features that would otherwise be washed away due to diffraction limit. We demonstrate that this all-optical collaboration between a diffractive solid-immersion encoder and the following decoder layers in air can resolve subwavelength phase and amplitude features of input objects in a highly compact design. To experimentally demonstrate its proof-of-concept, we used terahertz radiation and developed a fabrication method for creating monolithic multi-layer diffractive processors. Through these monolithically fabricated diffractive encoder-decoder pairs, we demonstrated phase-to-intensity <span>(({varvec{P}}to {varvec{I}}))</span> transformations and all-optically reconstructed subwavelength phase features of input objects (with linewidths of ~ λ/3.4, where λ is the illumination wavelength) by directly transforming them into magnified intensity features at the output. This solid-immersion-based diffractive imager, with its compact and cost-effective design, can find wide-ranging applications in bioimaging, endoscopy, sensing and materials characterization.</p>","PeriodicalId":72891,"journal":{"name":"eLight","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141504915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}