Photothermal Microscopy and Spectroscopy with Nanomechanical Resonators

The Journal of Physical Chemistry C, Journal Year: 2023, Volume and Issue: 127(45), P. 21915 - 21929

Published: Nov. 6, 2023

In nanomechanical photothermal absorption spectroscopy and microscopy, the measured substance becomes a part of detection system itself, inducing resonance frequency shift upon thermal relaxation. Suspended, nanometer-thin ceramic or 2D material resonators are innately highly sensitive detectors localized heat exchanges from substances on their surface integrated into resonator itself. Consequently, combined nanoresonator-analyte is self-measuring spectrometer microscope responding to substance's transfer over entire spectrum for which it absorbs, according intensity experiences. Limited by own thermostatistical fluctuation phenomena, nanoresonators have demonstrated sufficient sensitivity measuring trace analyte as well single particles molecules with incoherent light focused wide-field coherent light. They versatile in design, support various sampling methods─potentially including hydrated sample encapsulation─and hyphenation other spectroscopic methods, capable wide range applications fingerprinting, separation science, sciences.

Language: Английский

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Future Paths in Cryogenic Single-Molecule Fluorescence Spectroscopy

The Journal of Physical Chemistry C, Journal Year: 2023, Volume and Issue: 128(1), P. 3 - 18

Published: Dec. 22, 2023

In the last three decades, cryogenic single-molecule fluorescence spectroscopy has provided average-free understanding of photophysics and fundamental interactions at molecular scales. Furthermore, they propose original pathways applications in treatment storage quantum information. The ultranarrow lifetime-limited zero-phonon line acts as an excellent sensor to local perturbations caused either by intrinsic dynamical degrees freedom, or external perturbations, such those electric fields, elastic acoustic deformations, light-induced dynamics. Single aromatic hydrocarbon molecules, being sensitive nanoscale probing nanometer scales, are potential miniaturized platforms for integrated photonics. this Perspective, we look back some past advances optical microscopy perspectives future development.

Language: Английский

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An optofluidic antenna for enhancing the sensitivity of single-emitter measurements

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: March 21, 2024

Abstract Many single-molecule investigations are performed in fluidic environments, for example, to avoid unwanted consequences of contact with surfaces. Diffusion molecules this arrangement limits the observation time and number collected photons, thus, compromising studies processes fast or slow dynamics. Here, we introduce a planar optofluidic antenna (OFA), which enhances fluorescence signal from by about 5 times per passage, leads 7-fold more frequent returns volume, significantly lengthens diffusion within one passage. We use multi-parameter detection (sm-MFD), correlation spectroscopy (FCS) Förster resonance energy transfer (FRET) measurements characterize our OFAs. The advantages showcased examining both (ms) (50 μ s) dynamics DNA four-way (Holliday) junctions real-time resolution. FRET trajectories provide evidence absence an intermediate conformational state upper bound its lifetime. ease implementation compatibility various microscopy modalities make OFAs broadly applicable diverse range studies.

Language: Английский

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Review and Perspective of Single-Molecule Spectroscopy for Chemistry

Chinese Journal of Chemical Physics, Journal Year: 2024, Volume and Issue: 37(2), P. 125 - 136

Published: April 1, 2024

Single-molecule spectroscopy (SMS) has emerged as a powerful technique more than three decades after its initial optical detection in solid matrices. Over this period, numerous technological advancements have been made, leading to successful implementation of these methods across various scientific disciplines, such biology, chemistry, physics, and materials. While SMS found extensive utility the field particularly super-resolution imaging, application chemistry remains relatively limited. This review presents comprehensive overview diverse applications several areas, highlighting potential chemistry. Furthermore, we provide brief perspective on future development SMS, emphasizing promising prospects for advancing chemical research.

Language: Английский

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Efficient, nonparametric removal of noise and recovery of probability distributions from time series using nonlinear-correlation functions: Additive noise

The Journal of Chemical Physics, Journal Year: 2023, Volume and Issue: 159(5)

Published: Aug. 2, 2023

Single-molecule and related experiments yield time series of an observable as it fluctuates due to thermal motion. In such data, can be difficult distinguish fluctuating signal from noise. We present a method separating noise using nonlinear-correlation functions. The is fully nonparametric: No priori model for the system required, no knowledge whether continuous or discrete needed, number states not fixed, Markovian not. noise-corrected, functions converted system's Green's function; noise-corrected moments equilibrium-probability distribution. As demonstration, we analyze synthetic data three-state system. correlation compared another nonparametric approach-time binning remove noise, histogramming obtain has substantially better resolution in state space. develop formulas limits on quality needed recovery test them datasets varying size signal-to-noise ratio. show that ratio needs order greater than one-half before convergence scales at practical rate. With experimental benchmark positions populations their exchange rates are recovered with accuracy similar parametric methods. methods demonstrated here essential components building complete analysis only high-order

Language: Английский

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Nanomaterial-based single-molecule optical immunosensors for supersensitive detection

Biosensors and Bioelectronics X, Journal Year: 2022, Volume and Issue: 11, P. 100191 - 100191

Published: July 11, 2022

Unlike bulk materials, nanomaterials have unique properties that make them suitable for biosensor applications. Nanomaterial-based biosensors a series of advantages can help realize high throughput and ultrasensitive detection. In recent years, considerable research has been performed on integrating single-molecule immunosensors. This review provides an overview the various types used signal amplification in immunosensors, with focus development optics-based immunosensors using precious plasmonic noble metals (e.g., gold, silver), magnetic beads, quantum dots, upconversion nanoparticles, nanocomposites. particular, approach is presented to detect quantify biomolecular interactions antibody–antigen). Integrating supersensitive bio-devices expected offer significant trace element diagnosis early diagnosis.

Language: Английский

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Distinguishing Single-Metal Nanoparticles with Subdiffraction Spatial Resolution Using Variable-Polarization Fourier Transform Nonlinear Optical Microscopy

Chemical & Biomedical Imaging, Journal Year: 2023, Volume and Issue: 1(1), P. 91 - 98

Published: March 6, 2023

The development and use of interferometric variable-polarization Fourier transform nonlinear optical (vpFT-NLO) imaging to distinguish colloidal nanoparticles colocated within the diffraction limit is described. Using a collinear train phase-stabilized pulse pairs with orthogonal electric field vectors, polarization excitation fields are controllably modulated between linear, circular, various elliptical states. Polarization modulation achieved by precise control over time delay separating hundreds attoseconds. resultant emission from gold nanorods imaged 2D array detector correlated plasmon resonance frequency transformation. Gold length-to-diameter aspect ratios 2 support longitudinal surface at approximately 800 nm, which resonant fundamental carrier wavelength. Differences in intrinsic linear circular dichroism resulting variation their relative alignment respect laboratory frame enable differentiation separated 50 an approximate 5-fold improvement microscope. experimental results supported analytical simulations. In addition subdiffraction spatial resolution, vpFT-NLO method intrinsically provides polarization- frequency-dependent response nanoparticles-providing spectroscopic information content along super-resolution capabilities.

Language: Английский

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Orientation distributions of vacuum-deposited organic emitters revealed by single-molecule microscopy

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Oct. 2, 2023

Abstract The orientation of luminescent molecules in organic light-emitting diodes strongly influences device performance. However, our understanding the factors controlling emitter is limited as current measurements only provide ensemble-averaged values. Here, we use single-molecule imaging to measure transition dipole individual a state-of-the-art thermally evaporated host and thereby obtain complete distributions hyperfluorescence-terminal C545T. We achieve this by realizing ultra-low doping concentrations (10 −6 wt%) C545T minimising background levels reliably its photoluminescence. This approach yields >1000 system relevant vacuum-processed devices. Analysis solution- systems reveals that depend on nanoscale environment emitter. work opens door attaining unprecedented information determine future material for

Language: Английский

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Thousand-Fold Enhancement of Photothermal Signals in Near-Critical CO₂

The Journal of Physical Chemistry C, Journal Year: 2023, Volume and Issue: 127(7), P. 3619 - 3625

Published: Feb. 9, 2023

Photothermal (PT) microscopy has shown strong promise in imaging single absorbing nano-objects soft matter and biological systems. PT at ambient conditions usually requires a high laser power for sensitive detection, which prevents application to light-sensitive nanoparticles. In previous study of gold nanoparticles, we showed that the photothermal signal can be enhanced more than 1000-fold near-critical xenon compared glycerol, typical medium detection. this report, show carbon dioxide (CO2), much cheaper gas xenon, enhance signals similar way. We confine CO2 thin capillary easily withstands pressure (around 74 bar) facilitates sample preparation. also demonstrate enhancement magnetic circular dichroism magnetite nanoparticle clusters supercritical CO2. have performed COMSOL simulations support explain our experimental findings.

Language: Английский

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Spectral splitting of a stimulated Raman transition in a single molecule

Physical Review Research, Journal Year: 2023, Volume and Issue: 5(4)

Published: Dec. 14, 2023

The small cross-section of Raman scattering poses a great challenge for its direct study at the single-molecule level. By exploiting high Franck-Condon factor common-mode resonance, choosing large vibrational frequency difference in electronic ground and excited states operating $T<2\phantom{\rule{0.16em}{0ex}}\mathrm{K}$, we succeed driving coherent stimulated transition individual molecules. We observe model spectral splitting that serves as characteristic signature phenomenon hand. Our sets intrinsic optomechanical degrees freedom molecules applications solid-state quantum optics information processing.

Language: Английский

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