Publications by authors named "A N Tsypkin"

The study of plasma in liquid jets represents a significant area of research encompassing plasma science, dynamics, and properties. This paper presents experimental studies on plasma formation processes in liquid jets of water, ethanol, and isopropyl based on the dynamics of the third harmonic (TH) reflection from the induced plasma. Through time-resolved experiments, and theoretical estimations using the Keldysh theory, plasma properties including density and frequency for all three media are evaluated.

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To create self-controlled radiation photonics systems, it is necessary to have complete information about the nonlinear properties of the materials used. In this Letter, the vibrational mechanism of the giant low-inertia cubic nonlinearity of the refractive index of water in the terahertz (THz) frequency range is experimentally proven. Its dominance, which manifests itself when the temperature of the liquid changes, is demonstrated.

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Carbon dots (CDs) are light-emitting nanoparticles that show great promise for applications in biology and medicine due to the ease of fabrication, biocompatibility, and attractive optical properties. Optical chirality, on the other hand, is an intrinsic feature inherent in many objects in nature, and it can play an important role in the formation of artificial complexes based on CDs that are implemented for enantiomer recognition, site-specific bonding, etc. We employed a one-step hydrothermal synthesis to produce chiral CDs from the commonly used precursors citric acid and ethylenediamine together with a set of different chiral precursors, namely, L-isomers of cysteine, glutathione, phenylglycine, and tryptophan.

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We investigated data denoising in hyperspectral terahertz pulse time-domain holography. Using the block-matching algorithms adapted for spatio-temporal and spatio-spectral volumetric data we studied and optimized parameters of these algorithms to improve phase image reconstruction quality. We propose a sequential application of the two algorithms oriented on work in temporal and spectral domains.

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Luminescent molecules attached to resonant colloidal particles are an important tool to study light-matter interaction. A traditional approach to enhance the photoluminescence intensity of the luminescent molecules in such conjugates is to incorporate spacer-coated plasmonic nanoantennas, where the spacer prevents intense non-radiative decay of the luminescent molecules. Here, we explore the capabilities of an alternative platform for photoluminescence enhancement, which is based on low-loss Mie-resonant colloidal silicon particles.

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