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Science Advances Jun 2023The laser is one of the greatest inventions in history. Because of its ubiquitous applications and profound societal impact, the concept of the laser has been extended...
The laser is one of the greatest inventions in history. Because of its ubiquitous applications and profound societal impact, the concept of the laser has been extended to other physical domains including phonon lasers and atom lasers. Quite often, a laser in one physical domain is pumped by energy in another. However, all lasers demonstrated so far have only lased in one physical domain. We have experimentally demonstrated simultaneous photon and phonon lasing in a two-mode silica fiber ring cavity via forward intermodal stimulated Brillouin scattering (SBS) mediated by long-lived flexural acoustic waves. This two-domain laser may find potential applications in optical/acoustic tweezers, optomechanical sensing, microwave generation, and quantum information processing. Furthermore, we believe that this demonstration will usher in other multidomain lasers and related applications.
Topics: Phonons; Photons; Lasers; Optical Tweezers; Sound
PubMed: 37390201
DOI: 10.1126/sciadv.adg7841 -
Journal of Biophotonics Jan 2023
Topics: Optics and Photonics; Congresses as Topic
PubMed: 36511845
DOI: 10.1002/jbio.202380001 -
Nature Jun 2021The performance of light microscopes is limited by the stochastic nature of light, which exists in discrete packets of energy known as photons. Randomness in the times...
The performance of light microscopes is limited by the stochastic nature of light, which exists in discrete packets of energy known as photons. Randomness in the times that photons are detected introduces shot noise, which fundamentally constrains sensitivity, resolution and speed. Although the long-established solution to this problem is to increase the intensity of the illumination light, this is not always possible when investigating living systems, because bright lasers can severely disturb biological processes. Theory predicts that biological imaging may be improved without increasing light intensity by using quantum photon correlations. Here we experimentally show that quantum correlations allow a signal-to-noise ratio beyond the photodamage limit of conventional microscopy. Our microscope is a coherent Raman microscope that offers subwavelength resolution and incorporates bright quantum correlated illumination. The correlations allow imaging of molecular bonds within a cell with a 35 per cent improved signal-to-noise ratio compared with conventional microscopy, corresponding to a 14 per cent improvement in concentration sensitivity. This enables the observation of biological structures that would not otherwise be resolved. Coherent Raman microscopes allow highly selective biomolecular fingerprinting in unlabelled specimens, but photodamage is a major roadblock for many applications. By showing that the photodamage limit can be overcome, our work will enable order-of-magnitude improvements in the signal-to-noise ratio and the imaging speed.
Topics: Cells; Lasers; Lighting; Microscopy; Photons; Quantum Theory; Signal-To-Noise Ratio; Spectrum Analysis, Raman
PubMed: 34108694
DOI: 10.1038/s41586-021-03528-w -
Advanced Drug Delivery Reviews Jul 2021Extracellular Vesicles (EVs) are versatile carriers for biomarkers involved in the pathogenesis of multiple human disorders. Despite the increasing scientific and... (Review)
Review
Extracellular Vesicles (EVs) are versatile carriers for biomarkers involved in the pathogenesis of multiple human disorders. Despite the increasing scientific and commercial interest in EV application in diagnostics, traditional biomolecular techniques usually require consistent sample amount, rely on operator-dependent and time- consuming procedures and cannot cope with the nano-size range of EVs, limiting both sensitivity and reproducibility of results. The application of biophotonics, i.e. light-based methods, for the diagnostic detection of EVs has brought to the development of innovative platforms with excellent sensitivity. In this review, we propose an overview of the most promising and emerging technologies used in the field of EV-related biomarker discovery. When tested on clinical samples, the reported biophotonic approaches in most cases have managed to discriminate between nanovesicles and contaminants, achieved much higher resolution compared to traditional procedures, and reached moderate to excellent diagnostic accuracy, thus demonstrating great potentialities for their clinical translation.
Topics: Biomarkers; Extracellular Vesicles; Humans; Nanoparticles; Optical Phenomena; Optics and Photonics; Reproducibility of Results
PubMed: 33887403
DOI: 10.1016/j.addr.2021.04.014 -
Optics Letters Aug 2021Multimodal nonlinear microscopy combining third-harmonic generation (THG) with two- and three-photon-excited fluorescence (2PEF and 3PEF) is shown to provide a powerful...
Multimodal nonlinear microscopy combining third-harmonic generation (THG) with two- and three-photon-excited fluorescence (2PEF and 3PEF) is shown to provide a powerful resource for high-fidelity imaging of nucleoli and nucleolar proteins. We demonstrate that, with a suitably tailored genetically encoded fluorescent stain, the 2PEF/3PEF readout from specific nucleolar proteins can be reliably detected against the extranucleolar 2PEF/3PEF signal, enabling high-contrast imaging of the key nucleolar ribosome biogenesis components, such as fibrillarin. THG is shown to provide a versatile readout for unstained nucleolus imaging in a vast class of biological systems as different as neurons in brain slices and cultured HeLa cells.
Topics: Brain; HeLa Cells; Humans; Microscopy; Optical Imaging; Photons
PubMed: 34329236
DOI: 10.1364/OL.416300 -
Cytometry. Part a : the Journal of the... Aug 2019
Topics: Color; Flow Cytometry; Humans; Optics and Photonics; Spectrum Analysis
PubMed: 31038271
DOI: 10.1002/cyto.a.23779 -
Nano Letters Jul 2022Picocavities are sub-nanometer-scale optical cavities recently found to trap light, which are formed by single-atom defects on metallic facets. Here, we develop simple...
Picocavities are sub-nanometer-scale optical cavities recently found to trap light, which are formed by single-atom defects on metallic facets. Here, we develop simple picocavity models and discuss what is known and unknown about this new domain of atom-scale optics, as well as the challenges for developing comprehensive theories. We provide simple analytic expressions for many of their key properties and discuss a range of applications from molecular electronics to photocatalysis where picocavities are important.
Topics: Optics and Photonics; Spectrum Analysis, Raman
PubMed: 35793541
DOI: 10.1021/acs.nanolett.2c01695 -
Micron (Oxford, England : 1993) Oct 2020Super-resolution microscopy can reveal the subtle biological processes hidden behind the optical diffraction barrier. Plasmonics is a key nanophotonic that combines... (Review)
Review
Super-resolution microscopy can reveal the subtle biological processes hidden behind the optical diffraction barrier. Plasmonics is a key nanophotonic that combines electronics and photonics through the interaction of light with the metallic nanostructure. In this review, we survey the recent progresses on plasmonic-assisted super-resolution microscopy. The strong electromagnetic field enhancement trapped near metallic nanostructures offers a unique opportunity to manipulate the illumination scheme for overcoming the diffraction limit. Plasmonic nanoprobes, exploited as surface-enhanced Raman scattering (SERS) and plasmon-enhanced fluorescence nanoparticles, are a major category of contrast agent in super-resolution microscopy. The outstanding challenges, future developments, and potential biological applications are also discussed.
Topics: Biology; Electronics; Fluorescence; Metal Nanoparticles; Microscopy; Nanostructures; Optics and Photonics
PubMed: 32688264
DOI: 10.1016/j.micron.2020.102916 -
ACS Nano Nov 2020Advances in switchable microlasers have emerged as a building block with immense potential in controlling light-matter interactions and integrated photonics. Compared to...
Advances in switchable microlasers have emerged as a building block with immense potential in controlling light-matter interactions and integrated photonics. Compared to artificially designed interfaces, a stimuli-responsive biointerface enables a higher level of functionalities and versatile ways of tailoring optical responses at the nanoscale. However, switching laser emission with biological recognition has yet to be addressed, particularly with reversibility and wavelength tunability over a broad spectral range. Here we demonstrate a self-switchable laser exploiting the biointerface between label-free DNA molecules and dye-doped liquid crystal matrix in a Fabry-Perot microcavity. Laser emission switching among different wavelengths was achieved by utilizing DNA conformation changes as the switching power, which alters the orientation of the liquid crystals. Our findings demonstrate that different concentrations of single-stranded DNA lead to different temporal switching of lasing wavelengths and intensities. The lasing wavelength could be reverted upon binding with the complementary sequence through DNA hybridization process. Both experimental and theoretical studies revealed that absorption strength is the key mechanism accounting for the laser shifting behavior. This study represents a milestone in achieving a biologically controlled laser, shedding light on the development of programmable photonic devices at the sub-nanoscale by exploiting the complexity and self-recognition of biomolecules.
Topics: DNA; Lasers; Liquid Crystals; Nucleic Acid Hybridization; Optics and Photonics
PubMed: 33135892
DOI: 10.1021/acsnano.0c08219 -
Small (Weinheim An Der Bergstrasse,... Nov 2022Low-dimensional organic crystals (LOCs) have attracted increasing attention recently for their potential applications in miniaturized optoelectronics and integrated... (Review)
Review
Low-dimensional organic crystals (LOCs) have attracted increasing attention recently for their potential applications in miniaturized optoelectronics and integrated photonics. Such applications are possible owing to their tunable physicochemical properties and excellent charge/photon transport features. As a result, the precise synthesis of LOCs has been examined in terms of morphology modulation, large-area pattern arrays, and complex architectures, and this has led to a series of appealing structure-dependent properties for future optoelectronic applications. This review summarizes the recent advances in the precise synthesis of LOCs in addition to discussing their structure-property relationships in the context of optoelectronic applications. It also presents the current challenges related to organic crystals with specific structures and desired performances, and the outlook regarding their use in next-generation integrated optoelectronic applications.
Topics: Optics and Photonics
PubMed: 36057992
DOI: 10.1002/smll.202203961