Lysosomes are vital organelles vulnerable to injuries from diverse materials. Failure repair or sequester damaged lysosomes poses a threat cell viability. Here we report that cells exploit sphingomyelin-based lysosomal pathway operates independently of ESCRT reverse potentially lethal membrane damage. Various conditions perturbing organelle integrity trigger rapid calcium-activated scrambling and cytosolic exposure sphingomyelin. Subsequent metabolic conversion sphingomyelin by neutral...

The tuning of second (SHG) and third (THG) harmonic emission is studied in the model system LiNb 1−xTa xO 3 (0≤x≤1, LNT) between established edge compositions lithium niobate (LiNbO 3, x=0, LN) tantalate (LiTaO x=1, LT). Thus, existence optical nonlinearities order demonstrated ferroelectric solid solution system, question about suitability LNT field nonlinear quantum optics, particular as a promising material for frequency conversion with tunable composition, addressed. For this purpose,...

We study adiabatic light transfer in systems of two coupled waveguides with spatially varying detuning the propagation constants, providing an analogy to quantum phenomena rapid passage (RAP) and two-state stimulated Raman (two-state STIRAP). Experimental demonstration using a photoinduction technique confirms robust broadband character structures that act as directional couplers beam splitters, respectively.

Small-polaron hopping involved in charge transport Fe-doped congruent lithium niobate is investigated as a function of temperature and composition by means light-induced transient absorption spectroscopy. The relaxation dynamics the polaron population characterized individual activation energies within different ranges. A numerical investigation carried out Monte Carlo simulations reveals that these findings may be understood terms varying abundance types hops polarons perform among regular...

We demonstrate a simple technique to create large number of arbitrary optical structures in photorefractive Fe-doped lithium niobate (Fe:LN). The consists directly writing with focused laser beam at visible wavelength the desired on sample, taking advantage effect. Using computer-controlled translation stage, 1D patterns can be recorded allowing diffraction gratings or waveguide arrays realized. In contrast other laser-writing approaches, our method exploits solely sensitivity Fe:LN as...

Near-infrared (NIR) marker-based imaging is of growing importance for deep tissue and based on a considerable reduction optical losses at large wavelengths. We aim to extend the range NIR excitation wavelengths particularly values beyond 1.6 μm in order profit from low loss biological windows NIR-III NIR-IV. address this task by studying NIR-excitation NIR-emission conversion 1200 up 2400 nm example harmonic Mg-doped lithium niobate nanoparticles (i) using nonlinear diffuse femtosecond-pulse...

Transient absorption and photoluminescence are experimentally investigated in the polaronic reference system lithium niobate, LiNbO[Formula: see text] (LN), with aim to refine microscopic model of small polaron dynamics materials strong electron-phonon coupling. As a unique feature, our study is performed by using two different spectroscopic methods, crystals dopants enhancing photorefraction or damage resistance, over broad temperature range from 15-400 K. Although being self-consistent for...

Charge transport due to small polarons hopping among defective (bound polarons) and regular (free sites is shown depend in a non-trivial way on the value of stabilization energy provided by lattice distortion surrounding charge carriers. This energy, normally not directly accessible for bound using spectroscopic techniques, determined here combination experimental numerical methods important case electron [Formula: see text] defects prototype ferroelectric oxide lithium niobate. Our findings...

Two literature-known sulfido vanadates, Na3[VS4] and K3[VS4], were obtained through a straightforward scalable synthetic method. Highly crystalline powders of both compounds from the homogeneous molten phases starting materials via a─comparably rapid─solid-state technique. Low-temperature structure determination, ambient temperature powder diffraction, solid-state NMR spectroscopy verify previous structural reports indicate purity samples. Both show semiconductivity with optical band gap...

Abstract Femto-/nanosecond pulse-induced, red and near-infrared absorption is studied in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:msub> <mml:mtext>LiNb</mml:mtext> <mml:mn>1</mml:mn> <mml:mo>−</mml:mo> <mml:mi>x</mml:mi> </mml:mrow> </mml:msub> <mml:mtext>Ta</mml:mtext> <mml:mtext>O</mml:mtext> <mml:mn>3</mml:mn> </mml:math> ( <mml:mn>0</mml:mn> <mml:mtext>⩽</mml:mtext> , LNT) solid solutions with the aim of studying transient optical...

A strongly temperature-dependent photo-induced transient absorption is measured in 6.5 mol% magnesium-doped lithium niobate at temperatures ranging from 45 K to 225 K. This phenomenon interpreted as resulting the generation and subsequent recombination of oppositely charged small polarons. Initial two-photon absorptions generate separated The existence these polarons monitored by presence their characteristic absorption. decay this occurs series thermally assisted hops that facilitate merger...

In vivo tracking of harmonic nanoparticles (HNPs) in living animals is a technique not yet exploited, despite the great potential offered by these markers, due to lack an appropriate tool. The main drawback necessity excite nonlinear effects millimeter area widefield mode with sufficient signal noise ratio. Our approach this problem consists redesign laser space parameters region high energy per pulse and low repetition rate kHz regime, counter-trend actual microscope research technology. We...

The absorption features of optically generated, short-lived small bound electron polarons are inspected in congruent lithium tantalate, ${\rm LiTaO}_3$ (LT), order to address the question whether it is possible localize electrons at interstitial Ta_V}$:${\rm V_{Li}}$ defect pairs by strong, short-range electron-phonon coupling. Solid-state photoabsorption spectroscopy under light exposure and density functional theory used for an experimental theoretical access spectral polaron states...

Based on a model of coupled processes with differently time-dependent decay kinetics we present critical review photoluminescence (PL) and transient absorption (TA) experiments in undoped Mg or Fe-doped LiNbO

Photoinduced charge transport in lithium niobate for standard illumination, composition and temperature conditions occurs by means of small polaron hopping either on regular or defective lattice sites. Starting from Marcus-Holstein’s theory frequency we draw a quantitative picture illustrating two underlying microscopic mechanisms besides experimental observations, namely direct trapping migration-accelerated transport. Our observations will be referred to the typical outcomes transient...

The thermally activated, incoherent hopping of small electron polarons generated by continuous illumination in iron-doped lithium niobate is simulated a Marcus-Holstein model for which all the input parameters are known from literature. results calculations compared with comprehensive set data obtained photorefractive, photogalvanic and photoconductive measurements under green light excitation on samples different doping levels stoichiometries temperature range between room temperature. We...

Transient absorption is studied in Fe-doped lithium niobate single crystals with the goal to control and probe a blue feature related excitonic states bound Fe Li defect centers.The exciton deduced from comparison of ns-pump, supercontinuumprobe spectra obtained different Fe-concentration 2+/3+ -ratio, at pulse peak photon energies as well by signal separation taking well-known small polaron bands into account.As result, broad-band being characterized an cross-section up σ max (2.85 eV) = (4...

The diffraction patterns of 1D aperiodic Fibonacci gratings (FGs) are investigated here. We derive a set simple formulae which allow the finding positions and intensities strongest peaks amongst infinite ones present inside given reciprocal space interval , chosen according to user-defined threshold. In this way spectrum FGs their generalizations, generalised (GFGs), can be approximated good level as discrete, properly indexed with varying intensity, similarly what is done for periodic...

The ternary sulfido bismuthate K3[BiS3] is synthesized in quantitative yields. material exhibits nonlinear optical properties with strong second harmonic generation at arbitrary wavelengths the infrared spectral range and a notable laser-induced damage threshold of 5.22 GW cm-2 for pulsed laser radiation wavelength 1040 nm, pulse duration 180 fs, repetition rate 12.5 kHz. indicates semiconductivity direct band gap 2.51 eV. Dielectric impedance characterizations demonstrate κ values 6-13 1...

We investigate, theoretically and experimentally,the properties of diffraction spectra Fibonacci lattices with arbitrary spacings. show that, by means a suitable composition rule, sequence can be mapped into another one different lattice spacing. In this way we are able to define equivalence classes structures their generators, namely the sequences from which all others obtained compostion rule. that each class characterized given pattern is essentially generator, in sense most prominent...

Femto-/nanosecond pulse-induced, red and near-infrared absorption is studied in $\mathrm{LiNb}_{1-x}\mathrm{Ta}_{x}\mathrm{O}_3$ (LNT) solid solutions with the goal to probe intrinsic defect structure via formation, transport recombination of optically generated small bound electron polarons strong coupling lattice. As a result, long-lived transients are uncovered for LNT which exceed lifetimes LN LT by factor up 100 over entire range investigated compositions. At same time, starting...

Thin micropatterned lithium niobate (LiNbO 3 ) layers may be used for photonic components, actuators, and data storage devices because LiNbO exhibits nonlinear optical properties as well anisotropic polarizability ferroelectric behavior. Commonly, thin are integrated into device architectures by complex manufacturing algorithms including direct wafer bonding, mechanochemical thinning or mechanical cleavage of from bulk crystals, lithographic pattering and/or pattern transfer the layers. The...

The absorption features of optically generated, short-lived small bound electron polarons are inspected in congruent lithium tantalate, LiTaO

Abstract Lysosomes are vital organelles vulnerable to injuries from diverse materials. Failure repair or sequester damaged lysosomes poses a threat cell viability. Here we report that cells exploit sphingomyelin-based lysosomal pathway operates independently of ESCRT reverse potentially lethal membrane damage. Various conditions perturbing organelle integrity trigger rapid calcium-activated scrambling and cytosolic exposure sphingomyelin. Subsequent metabolic conversion sphingomyelin by...

Transmission Raman spectroscopy experiments were performed on iron doped congruent lithium niobate within two -in principle equivalent- configurations, namely Y(ZX)Y and Y(XZ)Y. While the former respects selection rules, other configuration gives a time dependent spectrum that, after transient of several minutes, finally results in mixture expected forbidden modes. This breaking rules is caused by spontaneous conversion part ordinarily polarized pump beam into an extraordinarily...