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Large geographic range, wide habitat specificity and broad range of prey (including a number of pests of protected crops) suggest that a predatory ladybird Cheilomenes propinqua can be considered as potential agent for biological control in greenhouses. We investigated the influence of day length (10, 12 and 14 hr), temperature (20 and 24°C) and diet (the green peach aphid Myzus persicae and eggs of the grain moth Sitotroga cerealella) on the rate of maturation, fecundity and induction of reproductive diapause in C. propinqua females of a laboratory population originated from Alexandria, Egypt. The proportion of diapausing females (i.e. those with poorly developed ovaries and well‐developed fat body) varied from 5% to 70% being higher at short day, low temperature and feeding on the grain moth eggs. This diapause, however, was not very stable: more than 20% of females kept under diapause‐inducing conditions started to lay eggs during 110 days, although their pre‐oviposition period was about 5 times longer than that of females which matured at the same temperature but at the long day and on the natural diet. Although not very stable, reproductive diapause significantly increased survival of starving females. Such a short‐term reproductive diapause can be considered as an adaptation to mild and short‐term subtropical winter. The results of our study suggest that C. propinqua mass rearing will be more intensive at the combination of high temperature, natural food (aphids) and long day (14 hr), whereas individuals intended for long‐term storage should be reared under moderate temperature (20°C) and short‐day (10 hr) conditions and should be fed on factitious food (the grain moth eggs).

For the first time, the data have been obtained on the effects of high-intensity terahertz (THz) radiation (with the intensity of 30 GW/cm2, electric field strength of 3.5 MV/cm) on human skin fibroblasts. A quantitative estimation of the number of histone Н2АХ foci of phosphorylation was performed. The number of foci per cell was studied depending on the irradiation time, as well as on the THz pulse energy. The performed studies have shown that the appearance of the foci is not related to either the oxidative stress (the cells preserve their morphology, cytoskeleton structure, and the reactive oxygen species content does not exceed the control values), or the thermal effect of THz radiation. The prolonged irradiation of fibroblasts also did not result in a decrease of their proliferative index.

The results of an experimental and theoretical study of the effect of an intense, single-period terahertz pulse on the ferroelectric polarization in a barium–strontium titanate film are presented. Modulation of the ferroelectric polarization in the field of a terahertz pulse with a strength of up to 23.2 MV/cm is demonstrated via generation of the second optical harmonic. The presence of a nonlinear dependence of the intensity of the second optical harmonic on the electric field strength of the THz pulse is shown.

We report on the investigation of the biological effects of high-power pulsed broadband terahertz (THz) radiation on human skin fibroblasts. Cells were exposed to THz pulses with peak intensity ~30 GW/cm2 and electrical field strength ~3.5 MV/cm for 1.5 hours. Phosphorylation of H2AX (γH2AX foci) can be caused by different reasons including DNA double stand breaks, heat induction and can be related to chromosomes stability. However, the γH2AX foci seem to be a proper marker for detection of the effect of intense terahertz pulses on cells. The kinetics of phosphorylated histone H2AX foci post terahertz radiation exposure is analyzed. We found that the number of phosphorylated H2AX foci in human skin fibroblasts remained almost unchanged within 24 hours following terahertz exposure.

Damage in a thin nickel film irradiated by subpicosecond pulses of terahertz (THz) radiation in the range of 1–3 THz at electric-field strengths up to 20 MV/cm at the center of a focal spot is observed. The damage threshold fluence is evaluated for single-pulse experiments. The damage pattern induced by multiple THz pulses has the appearance of a complex periodic structure in the form of elongated channels of metal film discontinuity that are perpendicular to the in-plane electric field direction of THz radiation.

The destruction of thin films of stainless steel with repeated exposure to ultrashort pulses of directional terahertz radiation has been studied. A terahertz pulse with a duration of picoseconds essentially models a nonresonant impact on an object of a quasi-permanent electric field with high intensity (up to 20 MV/cm).

In this study the effects of nano/microstructuring and surface chemistry on wettability, evaporation rate and the Leidenfrost temperature are experimentally investigated. The functional surfaces with two alternative patterns were originally fabricated via direct femtosecond laser surface processing of polished silicon wafer in air at a fluence slightly above ablation threshold. The droplet lifetime method was used to measure the evaporation rate of a water droplet (4.5 μL) at surface temperatures of 25–350°C and to determine the Leidenfrost temperature. Generally, after processing the functional surfaces with hierarchical surface morphology demonstrate enhanced wetting behavior, evaporation rate enhancement and positive shifts in the Leidenfrost temperature. The functional surfaces with a microgrooved surface pattern, extensively covered by flake-like nanostructures, exhibit strong superhydrophilicity, resulted in a significant temperature-dependent enhancement of evaporation rate (up to 6 times) and an increase of about 30°C in the Leidenfrost temperature relative to the polished surface. The functional surfaces with a microcratered surface pattern being only hydrophilic demonstrate a nearly twofold temperature-independent enhancement of evaporation rate. Thermostability tests showed the heating of the functional surfaces above 340°C to be resulted in a drastically deteriorated wettability and a reduction of evaporative heat transfer performance under repeated experiments.

Terahertz technology related to generation and detection of terahertz radiation, as well as its interaction with matter has been gaining much attention making it one of the most attractive research fields in turn of the 21st century and covering such major sectors as the semiconductor, medical, space and defense industries. With the advent of intense terahertz sources providing subpicosecond terahertz pulses with photon energies of 0.4–40 meV and maximum field strengths greater than 1 MV/cm, nonlinear effect studies of matter are now available. High-power terahertz sources open up a range of potential applications both in characterization and controlling of solid-state material properties that are elusive for other frequency domains. Recently, a new high-power terahertz source with a record-breaking electric field strength up to 100 MV/cm in the 0.1–5 THz range has been developed at JIHT RAS. In this paper, recent advances in terahertz technology related to intense terahertz field-matter interactions at field strengths above 1 MV/cm are discussed for the first time.

Optical imaging of spatial distribution of intensity in the focal spot of the terahertz pulse was developed. The technique is based on the THz electric field-induced second harmonic generation in the nonlinear centrosymmetric crystal (SrTiO3). The measurements of the spatial distribution of focal spot of terahertz radiation with the electric field strength over 1 MV/cm were conducted.

A versatile table-top high-intense source of terahertz radiation, enabling to generate pulses of both broadband and narrowband spectra with a tunable frequency up to 3 THz is presented. The terahertz radiation pulses are generated by optical rectification of femtosecond pulses of Cr:forsterite laser setup in nonlinear organic crystal OH1. Electric field strengths of broadband and narrowband terahertz pulses were achieved close to 20 MV/cm and more than 2 MV/cm, correspondingly. Experiments on excitation of spin subsystem oscillations of an antiferromagnetic NiO were carried out. Selective excitation of 0.42 THz mode was observed for the first time at room temperature by a narrowband terahertz pulses tuned close to mode frequency.

In this study, modern techniques of laser microsurgery of cell spheroids have been used to develop a new simple, reproducible model for studying the mechanisms of repair and regeneration in vitro. Nanosecond laser pulses were applied to perform a microdissection of the outer and the inner zones of the spheroids from dermal fibroblasts. To achieve effective dissection and preservation of spheroid viability, the optimal parameters were chosen: 355 nm wavelength, 100 Hz frequency, 2 ns pulse duration, laser pulses in the range of 7–9 μJ. After microdissection, we observed injury of the spheroids: the edges of the wound surface opened and the angular opening reached a value of more than 180°. As early as during the first hour after spheroid microdissection with laser radiation, the surviving cells changed their shape: cells on the spheroid surface and directly in the damaged area became rounded. One day after microdissection, the structure of the spheroids began to partially recover, the cells in the surface layers began to take the original flattened shape; debris of dead damaged cells and their fragments was gradually cleared from the spheroid composition. In the proposed model, the first data on stimulation of structure recovery of injured spheroids from dermal fibroblasts with a P199 synthetic polypeptide, which is used in cosmetology for the initiation of antiaging and regenerative effects in the skin, were received. After microdissection, recovery of the spheroids structure with a few surface layers of flattened imbricated arranged cells and polygonal cells of the inner zone in the presence of P199 peptide was faster than in the control group, and was completed within 7 days, presumably due to the remodeling of the survived cells.

We report the experimental results on generating pulsed terahertz (THz) radiation, frequency-tunable within the range . The THz pulse generation was implemented using the method of optical rectification of femtosecond laser pulses in the nonlinear organic crystal OH1. The frequency tuning of the THz radiation was provided by adaptive phase – amplitude modulation of the pump pulses from the Cr : forsterite laser system with a radiation wavelength of using the acoustooptical dispersion delay line.

Modern techniques of laser microsurgery of cell spheroids were used to develop a new simple reproducible model for studying repair and regeneration in vitro. Nanosecond laser pulses (wavelength 355 nm, frequency 100 Hz, pulse duration 2 ns) were applied to perform a microdissection of the outer and the inner zones of human bone marrow multipotent mesenchymal stromal cells (BM MMSC) spheroids. To achieve effective dissection and preservation of spheroid viability, the energy of laser pulses was optimized and adjusted in the range 7-9 μJ. After microdissection, the edges of the wound surface opened and the angular opening reached a value of more than 180°. The destruction of the initial spheroid structure was observed in the wound area, with surviving cells changing their shape into a round one. Partial restoration of a spheroid form took place in the first six hours. The complete structure restoration accompanying the reparative processes occurred gradually over seven days due to remodelling of surviving cells., Summary: The technique of precise nanosecond laser microsurgery of mesenchymal cell spheroids was used to develop a new simple reproducible model for studying repair and regeneration in vitro.

The periodic mesoscale structures arranged in a circular symmetry were found at the silicon surface exposed to radiation of the single femtosecond laser pulse with a Gaussian intensity profile in the ambient air conditions. These peculiar structures have the appearance of the protrusions of ∼10 nm height and of ∼600 nm width (at a FWHM) separately located inside the ablated region with a period of the incident laser wavelength. It was found that their position at the surface corresponds to the specified laser intensity slightly above the ablation threshold. The number of the formed periodic structures varies with the fluence of the incident laser pulse and in our experiments it was found to have changed from one to eleven. We suppose that formation of these mesoscale structures is caused by heating of a microscale volume to the strongly defined temperature. The theoretical model was proposed to explain the obtained data. It assumes that the interference of incident laser radiation with laser-induced surface electromagnetic waves results in generation of periodic distribution of electron temperature. Thus formation of the periodic structures at the specified laser intensity is attributed to periodically modulated absorption of laser energy at a focal laser spot.

The destruction of liquid tin at the extremely high strain rate caused by femtosecond laser pulses has been studied. The ablation and cavitation thresholds, as well as tensile stresses responsible for the destruction of liquid tin at a strain rate of ∼109 s–1, have been experimentally determined.

The ideal laser source for nonlinear terahertz spectroscopy offers large versatility delivering both ultra-intense broadband single-cycle pulses and user-selectable multi-cycle pulses at narrow linewidths. Here we show a highly versatile terahertz laser platform providing single-cycle transients with tens of MV/cm peak field as well as spectrally narrow pulses, tunable in bandwidth and central frequency across 5 octaves at several MV/em field strengths. The compact scheme is based on optical rectification in organic crystals of a temporally modulated laser beam. It allows up to 50 cycles and central frequency tunable from 0.5 to 7 terahertz, with a minimum width of 30 GHz, corresponding to the photon-energy width of Delta E=0.13 meV and the spectroscopic-wavenumber width of Delta(lambda(-1))=1.1 cm(-1). The experimental results are excellently predicted by theoretical modelling. Our table-top source shows similar performances to that of large-scale terahertz facilities but offering in addition more versatility, multi-colour femtosecond pump-probe opportunities and ultralow timing jitter. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

The propagation of short optical and terahertz pulses through a noncentrosymmetric (ferroelectric) film on a centrosymmetric substrate is considered. The effect of terahertz electro-induced second harmonic generation is observed in the film. It is shown that the difference in the group velocities of THz and optical pulses leads to a non-mirror-like dependence of the transient nonlinear-optical response upon a mirror image of the film–substrate structure relative to its surface.

Extremely intense few-cycle terahertz pulses exhibit complex nonlinear behavior under interaction with $n$-doped opaque Si having low field transmission of $\ensuremath{\sim}0.02%$. Transmission of a 700-fs pulse with central frequency $\ensuremath{\sim}1.5\phantom{\rule{0.16em}{0ex}}\mathrm{THz}$ through the Si sample increases up to $\ensuremath{\sim}8%$ for the external field strength of 5 MV/cm and then drops twofold at $\ensuremath{\sim}20\phantom{\rule{0.16em}{0ex}}\mathrm{MV}/\mathrm{cm}$. Electro-optical sampling measurements revealed formation of a single-cycle terahertz pulse at this field due to generation of a thin ionized layer by the first intense oscillation of the field. We explained the data obtained from the competition of processes of collision electron-phonon rate fast increase and saturation, as well as ionization under action of an intense THz field.

We report the results of experiments on estimation of femtosecond laser threshold intensity at which nanoparticles are removed from the substrate surface. The studies are performed with nanoparticles obtained by femtosecond laser ablation of pure aluminium in distilled water. The attenuation (or extinction, i.e. absorption and scattering) spectra of nanoparticles are measured at room temperature in the UV and optical wavelength ranges. The size of nanoparticles is determined using atomic force microscopy. A new method of scanning photoluminescence is proposed to evaluate the threshold of nanoparticle removal from the surface of a glass substrate exposed to IR femtosecond laser pulses with intensities 1011 – 1013 W cm-2.

We present the experimental results for the absorption spectra and photoluminescence of silicon nanoparticles synthesized by femtosecond laser ablation in distilled water under action of femtosecond laser pulses at a wavelength of 1048 nm with intensities in the range from 1010 to 1012 W/cm2.

In this paper we report the experimental data on modification and destruction of gold nanorods under action of single infrared femtosecond laser pulses in case of plasmon resonance at laser wavelength. The data on laser energy density, at which the shape of gold nanorods laid on silicon substrate in air conditions, is presented.

The first reliable observation of emission from a hot gas of free electrons in a metal with a cold lattice is reported. The emission is observed upon the irradiation of the metal with femtosecond laser pulses. The distinctive feature of this emission as compared to the case of equilibrium heating is the dependence of the emission quantum yield on the parameters of the electron-phonon interaction.

We report on the experimental observation of high-power terahertz-radiation-induced damage in a thin aluminum film with a thickness less than a terahertz skin depth. Damage in a thin metal film produced by a single terahertz pulse is observed for the first time. The damage mechanism induced by a single terahertz pulse could be attributed to thermal expansion of the film causing debonding of the film from the substrate, film cracking, and ablation. The damage pattern induced by multiple terahertz pulses at fluences below the damage threshold is quite different from that observed in single-pulse experiments. The observed damage pattern resembles an array of microcracks elongated perpendicular to the in-plane field direction. A mechanism related to microcracks' generation and based on a new phenomenon of electrostriction in thin metal films is proposed.

We report here an experimental and theoretical study on ultrafast switching of dielectric polarization in (Ba0.8Sr0.2)TiO3 thin films by a strong electric field of a nearly single-cycle THz pulse at different temperatures. Optical second harmonic generation (SHG) is used as a probe of the polarization in the terahertz pump-optical probe experiment. We describe an approach to interpretation of SHG response from the ferroelectric polydomain film excited by a short electric field pulse. We show that dielectric polarization induced by the THz field decreases while approaching the Curie temperature. Simulations with the help of the Duffing equation reproduce the experimental observations.

We report here an experimental study of ultrafast response of the dielectric polarization in (Ba 0.8 Sr 0.2 )TiO 3 thin films to a strong electric field of a nearly single-cycle THz pulse. The phenomenon of Second Harmonic Generation (SHG) is used as a probe of the polarization in the terahertz pump-optical probe experiment. SHG loops for THz pulses of different amplitudes were obtained. The SHG response is modelled assuming that the ferroelectric material is split into 180-degree domains. It is shown that intuitive model based on forced harmonic oscillator does not fully describe to the observed ultrafast ferroelectric response

The results of high-field terahertz transmission experiments on n-doped silicon (carrier concentration of $8.7\times10^{16}$ cm$^{-3}$) are presented. We use terahertz pulses with electric field strengths up to 3.1 MV cm$^{-1}$ and a pulse duration of 700 fs. Huge transmittance enhancement of $\sim$90 times is observed with increasing of the terahertz electric field strengths within the range of 1.5--3.1 MV cm$^{-1}$.

Precisely controlled sequences of ultrashort laser pulses are required in various scientific and engineering applications. We developed a phase-only acousto-optic pulse shaping method for replication of ultrashort laser pulses in a TW laser system. A sequence of several Fourier-transform-limited pulses is generated from a single femtosecond laser pulse by means of applying a piecewise linear phase modulation over the whole emission spectrum. Analysis demonstrates that the main factor which limits maximum delay between the pulse replicas is spectral resolution of the acousto-optic dispersive delay line used for pulse shaping. In experiments with a Cr:forsterite laser system, we obtained delays from 0.3 to 3.5 ps between two replicas of 190 fs transform-limited pulses at the central wavelength of laser emission, 1230 nm.

The exploration of high field phenomena in the THz frequency range (0.1–10 THz) requires advanced THz laser technology to cope with the requirements of versatile source to drive either non-resonant or selective dynamics [1, 2]. Here we present a laser-based THz source which is able to provide both intense single-cycle pulses up to 50 MV/cm as well as narrowband radiation at MV/cm field strength tunable across a frequency range of 0.5–8 THz and tunable in spectral bandwidth. The source is based on optical rectification of a Cr:forsterite laser [3, 4] in large-size organic crystals [5].

This paper provides a brief overview of the current state of research in the field of laser microsurgery of preimplantation embryos. The combined system femtosecond laser tweezers-scalpel developed in JIHT RAS is described. A scheme of device and peculiarities of functioning its nodes as well as the ground for the choice of their parameters are presented. The results of the development of methodology for noncontact polar body biopsy of the preimplantation embryo are also presented to demonstrate the potentials of the combined multi-purpose system femtosecond laser tweezers-scalpel.

We have studied the efficiency of microsurgery of a cell membrane in mesenchymal stem cells and the posterior cell viability under the localised short-time action of femtosecond IR laser pulses aimed at noncontact delivery of specified substances into the cells.

Using an interferometric continuous monitoring technique, we have investigated the motion of the surface of an aluminium target in the case of femtosecond laser ablation at picosecond time delays relative to the instant of laser exposure. Measurements of the temporal target dispersion dynamics, molecular dynamics simulation results and the morphology of the ablation crater have demonstrated a thermomechanical (spall) nature of the disruption of the condensed phase due to the cavitation-driven formation and growth of vapour phase nuclei upon melt expansion, followed by the formation of surface nanostructures upon melt solidification. The tensile strength of heated aluminium in a condensed state has been determined experimentally at an expansion rate of ~109 s-1.

We present the experimental data on the direct measurements of spatial distribution of the terahertz (THz) pulse intensity profile using a commercial silicon-based charge-coupled device (CCD) camera in the spectral range from 1-3 THz. A method to measure the dimensions of a high-intensity THz radiation beam in the focal plane using the CCD camera is proposed and experimentally verified.

IR femtosecond laser pulses were used for microsurgery of a cell membrane aimed at local and short-duration change in its permeability and injection of specified extracellular substances into the cells. The possibility of noncontact laser delivery of the propidium iodide fluorescent dye and the pEGFP plasmid, encoding the green fluorescent protein, into the cells with preservation of the cell viability was demonstrated.

We present a THz source providing multi-octave as well as narrowband spectra at electric field up to tens MV/cm. The emission is tunable in frequency over 0.5–8 THz and in relative bandwidth over 2%–300%.

An interferometric method is developed and realised using a frequency-modulated pulse for diagnosing a dynamics of fast deformations with a spatial and temporal resolution under the action of a single laser pulse. The dynamics of a free surface of a submicron-thick aluminium film is studied under an action of the ultrashort compression pulse with the amplitude of up to 14 GPa, excited by a femtosecond laser heating of the target surface layer. The spallation strength of aluminium was determined at a record high deformation rate of 3 × 109 s-1.

The results are presented of the works in the field of development of equipment, investigation techniques, and technologies for biology and medicine performed in the Joint Institute for High Temperatures of the Russian Academy of Scienses (JIHT RAS). On the base of the new generation infrared femtosecond lasers, the experimental models are developed and manufactured of laser tweezers, scalpel, and the “tweezers-scalpel” combined system. The results are presented of the experimental studies on the noncontact mammalian cell fusion (blastomeres of mouse embryos on day 1.5 of development) by means of the femtosecond laser pulses.

The opto-mechanical characteristics, such as the specific mechanical recoil momentum, the specific impulse, and the energy efficiency, of the laser ablation of flat polymer targets ((C2F4) n , (CH2O) n ) have been determined experimentally for the first time for the case of excitation with femtosecond pulses (τ ∼ 45–70 fs) of UV-IR (λ ∼ 266, 400, 800 nm) laser radiation (I 0 up to 1015 W/cm2) under normal atmospheric and vacuum (p ∼ 10−4 mbar) conditions. The efficiency of mechanical recoil momentum generation is analyzed for various regimes of the laser irradiation.

We present the results of an experimental study of the ablation spectral energy thresholds for a number of polymer materials ((C2F4) n , (CH2O) n ) exposed to femtosecond (τ0.5 ~ 45–70 fs) laser pulses (λ ~ 266, 400, 800 nm) under atmospheric conditions and under vacuum (p ~ 10–2 Pa). We have analyzed the energy thresholds and the efficiency of optical, thermophysical, and gasdynamic processes in laser ablation vs. the laser pulse duration and photon energy.

Results of investigation on spectral-energy thresholds, rates, and mass flow rates of laser ablation of structural materials (Cu, Ti, Zr, Nb, Mo) of high-energy photonics are presented. The data were obtained by means of an experimental diagnostic module developed for study of multifactor interaction processes between UV-near IR femtosecond laser pulse radiation and condensed media in vacuum.

Experimental research results are presented on the formation dynamics and macrostructure of optical discharges of condensed matter of a polymer series ((C2F4)n, (CH2O)n) under the action of a femtosecond laser (τ0.5 ∼ 45–70 fs) pulses (I0 ∼ 1013−1015 W/cm2) in the UV — NIR spectral region (λ ∼ 266, 400, 800 nm) under air and vacuum conditions. Electron density distributions in the near-surface area of the optical discharge, vapor expansion, and velocities of shock-wave front propagation are determined for the first time by precise laser pulse micro-interferometry with high spatial and time resolution. The correspondence is shown of the values of the laser ablation spectral-energy threshold, as determined by interference microscopy and the interferometry of a gas-plasma flow. An estimation technique for the total momentum of light-erosion gas-plasma flow in the sub-nanonewton range is proposed and implemented for the first time. The results of comparative analysis are presented on the laser radiation conversion efficiency at different stages of femtosecond optical discharges.

We combine theoretical and experimental methods to study the processes induced by fast laser heating of metal foils. These processes reveal themselves through motion of frontal (irradiated) and rear-side foil boundaries. The irradiated targets are 0.3-2 micron thick aluminum foils deposited on much thicker (150 microns) glass plate. The instant boundary positions is measured by pump-probe technique having ∼40-150 fs time and ∼1 nm spatial resolutions. Ultrashort laser pulse transforms a frontal surface layer with thickness dT into two-temperature (Te ≫ Ti) warm dense matter state. Its quantitative characteristics including its thickness are defined by poorly known coefficients of electron-ion energy exchange α and electron heat conductivity κ. Fast laser heating rises pressure in the dT-layer and therefore produce acoustic waves. Propagation and reflection from the frontal and rear boundaries of these waves causes the displacement Δx (t) of boundary positions. Pressure wave profiles, and hence functions Δx (t), depend on thickness dT. This is why the experimental detection of Δx (t) opens a way to accurate evaluation of the coefficients α and κ (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Enhancement of Kα yield from a metal foil covered with metal rods of submicron sizes, with low aspect ratio, irradiated by a p-polarized femtosecond laser pulses of about 1017 W/cm2 intensity is demonstrated. Obtained relative increase in Kα X-ray line emission is explained with a model of vacuum heating of fast electrons.

We study the charcteristics of X-ray radiation of a laser plasma generated in the interaction of a femtosecond pulse with solid targets in an air medium and conside the possibility of using it for radiography. We show that the mechanism for generating X-ray radiation in the interaction of short, powerful laser pulses with solid targets in a gas atmosphere is related to the generation of fast electrons in the gas breakdown region. We prove experimentally that under such conditions, even under relatively low laser radiation densities

In this Letter, we investigate the nonlinear effects of extremely intense few-cycle terahertz (THz) pulses (generated from the organic crystal 4-NN, NN-dimethylamino-4'4'-N'N'-methyl-stilbazolium 2, 4, 6 trimethylbenzenesulfonate, with peak electrical fields of a few MV/cm) on the carrier dynamics in n-doped semiconductor thin film In0.53Ga0.47As. By performing open-aperture Z-scan measurements and recording the transmitted THz energy through semiconductor sample, we observed a strong THz absorption bleaching effect at high fields, followed by an absorption enhancement at even higher fields. We attribute our observations to a crossover from pure intraband carrier dynamics to an interplay between intraband carrier heating and interband carrier generations.

A description is made of the experimentaldiagn ostic module with femtosecond terawatt laser complex (τ 0.5 ~ 45-70 fs, λ = 266, 400, and 800 nm) and of the pioneering procedure of combined ultrahigh� speed interferometry and interference microscopy (Michelson and Mach-Zehnder schemes) of the pro� cesses of interaction between ultrashort laser pulses and condensed media in vacuum. Results are given for the first time of the investigation of spectralenergy thresholds and rates of laser ablation of a number of solid� state media using elements of the polymer series (C2F4)n, (CH2O)n in the UV-NIR wavelength range of laser radiation in atmospheric conditions and in vacuum p ~ 10 -2 Pa.