Article
Chemistry, Physical
Hui Li, Xiaochun Gong, Hongcheng Ni, Peifen Lu, Xiao Luo, Jin Wen, Youjun Yang, Xuhong Qian, Zhenrong Sun, Jian Wu
Summary: By precisely controlling the waveform of ultrashort laser pulses, the electronic and nuclear motions in molecules can be manipulated on extremely short timescales. This Perspective summarizes recent advances in ultrafast laser techniques for manipulating molecular reactions based on waveform control of intense ultrashort laser pulses, providing new insights into the coherent control of molecular dynamics.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Yusuke Yoneda, Hikaru Kuramochi
Summary: Photochemical reactions occur in the electronically excited state, which is effectively represented by a multidimensional potential energy surface (PES) with a vast degree of freedom of nuclear coordinates. Recently, fully time-domain resonant two-dimensional Raman spectroscopy has emerged as a potentially powerful tool to provide unique information about the coupling between vibrational manifolds in the excited state. In this study, we demonstrate time-domain resonant two-dimensional impulsive stimulated Raman spectroscopy (2D-ISRS) of excited states using sub-10fs pulses based on the rapid scan of the time delay, which facilitates the efficient collection of time-domain vibrational signals with high sensitivity.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Optics
Walker Peterson, Julia Gala de Pablo, Matthew Lindley, Kotaro Hiramatsu, Keisuke Goda
Summary: Broadband Raman spectroscopy is a valuable tool for understanding samples via label-free measurements of their molecular vibrations. The chemically specific fingerprint and low-frequency or terahertz regions are highly complementary, and simultaneous measurement of both regions provides comprehensive information about molecular structures and interactions. By using Sagnac-enhanced impulsive stimulated Raman scattering and Fourier-transform coherent anti-Stokes Raman scattering for dual-detection, we have achieved ultrafast broadband Raman spectroscopy covering both THz and fingerprint regions.
ADVANCED PHOTONICS
(2022)
Article
Spectroscopy
Mauro Falconieri, Serena Gagliardi, Flaminia Rondino, Michele Marrocco, Waruna D. Kulatilaka
Summary: Impulsive stimulated Raman scattering (ISRS) is a nonlinear coherent technique for measuring the vibrational spectrum of samples, allowing for easy access to low-wavenumber Raman spectrum. Recent advancements have enabled fast and real-time Raman spectrum visualization in bulk, transparent liquids, without the drawbacks of microbubble creation or thermal instabilities. This innovative method is suitable for vibrational microscopy applications, contributing to studies of molecular vibrations and intermolecular force constants.
JOURNAL OF RAMAN SPECTROSCOPY
(2021)
Article
Chemistry, Physical
Marco Gandolfi, Liwang Liu, Pengfei Zhang, Mansour Kouyate, Robbe Salenbien, Francesco Banfi, Christ Glorieux
Summary: Two models based on Debye and Havriliak-Negami assumptions have been proposed to analyze Impulsive Stimulated Thermal Scattering (ISTS) signals, explicitly considering the relaxation of specific heat and thermal expansion in the response. These models were applied to experimental ISTS signals acquired on supercooled glycerol, allowing for the retrieval of frequency-dependent specific heat and thermal expansion up to the sub-100 MHz frequency range, and comparison of fragility and time scale probed by various susceptibilities.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Multidisciplinary Sciences
Haonan Lin, Hyeon Jeong Lee, Nathan Tague, Jean-Baptiste Lugagne, Cheng Zong, Fengyuan Deng, Jonghyeon Shin, Lei Tian, Wilson Wong, Mary J. Dunlop, Ji-Xin Cheng
Summary: The study presents a system for acquiring high-resolution SRS spectra using a polygon scanner, while significantly improving signal-to-noise ratio through the use of a spatial-spectral residual learning network. The authors demonstrate high-speed imaging and tracking of multiple biomolecules in the fingerprint region using a polygon-based ultrafast delay scanner and deep learning framework.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Mauro Falconieri, Davide Tedeschi, Serena Gagliardi, Flaminia Rondino, Michele Marrocco, Waruna D. D. Kulatilaka
Summary: Femtosecond coherent Raman techniques are valuable for sensitive and non-intrusive measurements of temperature, pressure, and composition of gas mixtures. This paper demonstrates an experimental setup using a low-energy and low-average-power femtosecond oscillator to measure the pure-rotational spectrum of nitrogen at atmospheric pressure. Gas temperature can be derived with reasonable accuracy using a simplified model to analyze the experimental data.
APPLIED SCIENCES-BASEL
(2022)
Article
Optics
Giulia Zanini, Giuliano Scarcelli
Summary: Brillouin spectroscopy is a promising technique for noninvasively probing the mechanical properties of biologically relevant materials. In this study, the authors derive a signal localization theory and design an improved SBS spectrometer, which shows significant improvements in acquisition speed and spectral precision.
Article
Chemistry, Physical
Shaina Dhamija, Garima Bhutani, Ajay Jayachandran, Arijit K. De
Summary: This paper revisits the usefulness of a chirped broadband probe and spectral dispersion for obtaining Raman spectra under nonresonant/resonant impulsive excitation. A general methodology is presented for phasing the time-domain low-frequency oscillations without probe pulse compression and retrieving the absolute phase. The method is applied to solvents and molecules, and the periodic intensity modulation observed along detection wavelengths is explained using a simple electric field interaction picture.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Optics
Sean p. O'connor, Dominik a. Doktor, Marlan o. Scully, V. L. A. D. I. S. L. A. V. V. Yakovlev
Summary: Brillouin microscopy has emerged as a powerful tool for measuring mechanical properties in biomedical sensing and imaging applications. Impulsive stimulated Brillouin scattering (ISBS) microscopy has been proposed for faster and more accurate measurements. The spectral resolution of ISBS-based signal has not been significantly explored. This study investigates the ISBS spectral profile and develops novel methodologies for accurate spectral assessment, providing means for improved spectral resolution measurements.
Article
Multidisciplinary Sciences
Raphael Jannin, Yuri van der Werf, Kees Steinebach, Hendrick L. Bethlem, Kjeld S. E. Eikema
Summary: The Pauli exclusion principle has a significant impact on the structure of matter and particle interaction. Recent experiments have confirmed the existence of Pauli blockade in an optically trapped Fermi gas of He-3.
NATURE COMMUNICATIONS
(2022)
Article
Optics
Benedikt Krug, Nektarios Koukourakis, Jochen Guck, Juergen Czarske
Summary: The impulsive stimulated Brillouin microscopy shows promise for fast, non-contact measurements of the elastic properties of biological samples, with high potential for various applications.
Article
Spectroscopy
Keisuke Seto, Takayoshi Kobayashi, Eiji Tokunaga
Summary: Dynamic light scattering (DLS) is a method for analyzing colloidal systems based on refractive index fluctuations. This paper demonstrates the theoretical feasibility of nonlinear dynamic light scattering (NLDLS) using stimulated Raman effect to reflect molecular vibration. By interfering with two pump beams, the spatial Fourier component of the imaginary part of the third-order nonlinear susceptibility can be extracted, providing mesostructural sensitivity with molecular vibration selectivity.
JOURNAL OF RAMAN SPECTROSCOPY
(2023)
Article
Chemistry, Physical
Giovanni Batignani, Carlotta Sansone, Carino Ferrante, Giuseppe Fumero, Shaul Mukamel, Tullio Scopigno
Summary: A two-color impulsive vibrational scattering experiment is proposed to decode nuclear displacements along different normal modes and reveal multidimensional potential energy surfaces. The interference between multiple pathways resonant with the excited-state manifold that generate the Raman signal is utilized to experimentally tune their relative phase, addressing key issues in photophysical and photochemical processes.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Physical
Pardeep Kumar, Eduard Fron, Haruko Hosoi, Hikaru Kuramochi, Satoshi Takeuchi, Hideaki Mizuno, Tahei Tahara
Summary: LSSmOrange exhibits a large energy gap between absorption and emission due to excited-state proton transfer, and the bimodal ESPT dynamics is attributed to structural heterogeneity of the chromophore.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Materials Science, Multidisciplinary
M. A. Conway, J. B. Muir, S. K. Earl, M. Wurdack, R. Mishra, J. O. Tollerud, J. A. Davis
Summary: This study successfully identifies and separates the optically excited biexciton in monolayer WS2 using two-quantum multidimensional coherent spectroscopy (2Q-MDCS), and measures the binding energy of the biexciton. The biexciton is composed of two bright excitons in opposite valleys.
Article
Instruments & Instrumentation
Giacomo Jarc, Shahla Yasmin Mathengattil, Francesca Giusti, Maurizio Barnaba, Abhishek Singh, Angela Montanaro, Filippo Glerean, Enrico Maria Rigoni, Simone Dal Zilio, Stephan Winnerl, Daniele Fausti
Summary: We report the realization and commissioning of an experiment dedicated to studying the optical properties of light-matter hybrids in crystalline samples embedded in an optical cavity. The experimental setup allows for the investigation of weak and strong coupling regimes between a tunable optical cavity and low energy degrees of freedom. The setup includes the positioning of crystalline samples in cavities of different quality factors, tuning of cavity length at cryogenic temperatures, and optical characterization using a broadband THz spectrometer. The versatility of the setup is demonstrated by studying vibrational strong coupling in CuGeO3 single crystal at cryogenic temperatures.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Multidisciplinary Sciences
Angela Montanaro, Francesca Giusti, Matteo Zanfrognini, Paola Di Pietro, Filippo Glerean, Giacomo Jarc, Enrico Maria Rigoni, Shahla Y. Mathengattil, Daniele Varsano, Massimo Rontani, Andrea Perucchi, Elisa Molinari, Daniele Fausti
Summary: The authors investigate the optical response of bulk black phosphorus to mid-infrared pulses, and find that while above-gap excitation leads to a broadband light-induced transparency, sub-gap pulses drive an anomalous response, peaked at the single-layer exciton resonance.
NATURE COMMUNICATIONS
(2022)
Article
Optics
Giorgia Sparapassi, Stefano M. Cavaletto, Jonathan Tollerud, Angela Montanaro, Filippo Glerean, Alexandre Marciniak, Fancesca Giusti, Shaul Mukamel, Daniele Fausti
Summary: This study presents a novel approach to transient Raman spectroscopy by combining stochastic probe pulses and covariance-based detection to measure stimulated Raman signals in alpha-quartz. The experimental results and theoretical description demonstrate the feasibility of 2D-Raman experiments based on stochastic-probe schemes, offering new capabilities not available in mean-value-based techniques.
LIGHT-SCIENCE & APPLICATIONS
(2022)
Article
Chemistry, Physical
Viswanathan Vinitha, Venkateswara Rao Mundlapati, Alexandre Marciniak, Micka el Carlos, Hassan Sabbah, Loic Nogues, Anthony Bonnamy, David Murat, Odile Coeur-Joly, Christine Joblin
Summary: Polycyclic aromatic hydrocarbons (PAHs) are important species in astrophysical environments and studying them in samples like meteorites and laboratory analogues of stardust is crucial. Analyzing PAHs in these samples is challenging due to their limited quantity. In this study, the researchers used laser desorption ionization mass spectrometry coupled with ion trapping to analyze isomers of PAHs and achieved successful differentiation.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Computer Science, Artificial Intelligence
Francesco Guzzi, George Kourousias, Fulvio Bille, Roberto Pugliese, Alessandra Gianoncelli, Sergio Carrato
Summary: This article introduces Sci-ComPty, a software framework that aims to simulate ptychography datasets and test advanced reconstruction algorithms. The software leverages GPU accelerated processing through the PyTorch CUDA interface, enabling the design of new methods. The authors also present improved position refinement and rPIE algorithms, with results shown on synthetic and real datasets.
PEERJ COMPUTER SCIENCE
(2022)
Article
Multidisciplinary Sciences
Matteo Ippoliti, Fulvio Bille, Andreas G. Karydas, Alessandra Gianoncelli, George Kourousias
Summary: The study of X-ray fluorescence (XRF) emission spectra is a powerful technique used in various fields, and this work introduces an X-ray-tracing application that can inversely reconstruct a 3D sample topography to quantitatively correct the self-absorption effects on XRF signal.
SCIENTIFIC REPORTS
(2022)
Article
Spectroscopy
Matteo Ippoliti, Francesco Guzzi, Alessandra Gianoncelli, Fulvio Bille, George Kourousias
Summary: X-ray fluorescence (XRF) spectroscopy is widely used in microscopy for characterizing presence of elemental species in a sample. In this work, a web-based application is introduced, which allows users to load XRF data and interactively set up fits and inspect results in a simple GUI. The application can be accessed locally through a web browser, but runs remotely on a cloud, eliminating the need for software installation.
X-RAY SPECTROMETRY
(2023)
Article
Biology
Francesco Guzzi, Alessandra Gianoncelli, Fulvio Bille, Sergio Carrato, George Kourousias
Summary: Computational techniques can overcome the limitations of traditional imaging methods, such as time restrictions, resolution, and optics flaws. While simple methods may be sufficient for controlled setups or previews, complex computational methods are needed for advanced setups, acquisition modalities, or high uncertainty. Automatic Differentiation, a subfield of Artificial Intelligence, can provide a functional solution if a GPU implementation is available. This paper demonstrates how a framework designed for one optimization problem can be applied to various X-ray imaging inverse problems.
Article
Chemistry, Physical
Angela Montanaro, Kyu Hyung Park, Francesca Fassioli, Francesca Giusti, Daniele Fausti, Gregory D. Scholes
Summary: In organic bulk heterojunction materials, charge delocalization plays a vital role in generating free carriers. Pump-push-probe experiments with mid-infrared push pulses were performed and identified three types of charge transfer excitons (CTXs): delocalized, localized, and trapped. Delocalized CTXs can be promoted by resonant mid-infrared push pulses, while trapped CTXs are non-responsive. The presence of delocalized CTXs emphasizes the importance of engineering the microstructure and energetics of the donor-acceptor interface in photovoltaic applications.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Optics
A. Dimitriou, V Loriot, A. Marciniak, T. Barillot, S. Danakas, F. Lepine, C. Bordas, S. Cohen
Summary: The nonlinear single and double ionization of Sr atoms induced by interaction with 800-nm laser pulses is experimentally investigated. The study reveals different ionization processes depending on the laser intensity, with a transition from multiphoton ionization to threshold ionization structures at higher intensities.