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The spectral features of high-order harmonic spectra can provide rich information for probing the structure and dynamics of molecules in intense laser fields. We theoretically study the high harmonic spectrum with the laser polarization direction perpendicular to the NO molecule and find a minimum structure in the plateau region of the harmonic spectrum. Through analyzing the time-dependent survival probability of different electronic orbitals and the time-dependent wave packet evolution, it is found that this minimum position is caused by the harmonic interference of HOMO a, HOMO-1, and HOMO-3 a orbitals. Moreover, this interference minimum is discovered over a wide frequency range of 0.087 a.u. to 0.093 a.u., as well as a range of driving laser intensities with peak amplitudes between 0.056 a.u. and 0.059 a.u.. This study sheds light on the multi-electron effects and ultrafast dynamics of inner-shell electrons in intense laser pulses, which are crucial for understanding and controlling chemical reactions in molecules.
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http://dx.doi.org/10.1364/OE.495031 | DOI Listing |
J Phys Chem Lett
September 2025
Hunan Key Laboratory of Nanophotonics and Devices, School of Physics, Central South University, Changsha 410083, People's Republic of China.
NbOCl has garnered interest owing to its second-order nonlinear optical properties, but the influence of thickness on its third-harmonic generation (THG) and excited-state dynamics has not been fully investigated. Here, mechanically exfoliated NbOCl flakes were found to produce THG and second-harmonic generation (SHG), simultaneously, and to show a nonmonotonic dependence on sample thickness. The increase in thickness leads to a decrease in the bandgap.
View Article and Find Full Text PDFJ Phys Condens Matter
September 2025
Mindanao State University, Marawi City, Marawi City, 9700, PHILIPPINES.
We study the dynamics and thermodynamics of a harmonically trapped colloidal particle driven by active noise with long-range memory. The active force is modeled as a stationary Gaussian process with a power-law decay, allowing us to interpolate between short- and long-time regimes by varying {the power law exponent $\alpha$}. In the overdamped setting, we derive exact solutions for the particle's position statistics and two-time correlations, and characterize how active noise affects its relaxation spectrum.
View Article and Find Full Text PDFNMR Biomed
October 2025
School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, QLD, Australia.
The ultrahigh field magnetic resonance imaging (MRI) superconducting magnets require a high homogeneous magnetic field within the diameter of spherical volume (DSV) to generate high-quality images. Spherical harmonic-based B shimming relies significantly on the fitting process, which can be computationally demanding, particularly when managing multiple shim coils. The study presents an automatic room-temperature shimming approach that iteratively adjusts shim coil currents to enhance magnetic field homogeneity, using the full width at half maximum (FWHM) of the spectrum as a metric.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
August 2025
CINBIO, Universidade de Vigo, Department of Physical Chemistry, Campus Universitario As Lagoas-Marcosende, Universidade de Vigo, Vigo, 36310, Spain.
Chiral organic-inorganic hybrid metal halides have emerged as a promising class of materials for spin-controlled optical and optoelectronic effects and related applications. Chiral hybrid metal halides generally crystallize in non-helical space groups. Herein, we report the discovery of zero-dimensional (0D) chiral (R/S-MBA)SnBr (MBA: methylbenzylammonium cation) single crystals with enantiomorphic lattice helicity.
View Article and Find Full Text PDFSci Adv
August 2025
ARC Centre of Excellence for Transformative Meta-Optical Systems (TMOS), Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, ACT 2601, Australia.
Transition metal dichalcogenides are promising quantum materials because of unique exciton-photon interactions. These interactions can be enhanced by coupling with resonant photonic structures, especially in the nonlinear light emission processes like second-harmonic generation (SHG). However, excitonic absorption may dampen SHG.
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