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IR laser radiation of XeI atoms in the range of 1700–2050 nm is obtained for the first time upon the pumping of xenon and mixtures of it with helium and argon by a pulsed longitudinal induction discharge. The spectrum of generation consists of two lines with wavelengths of 1733 nm and 2026 nm. The half-amplitude duration of the optical radiation is 60 ± 2 ns (FWHM).

The results of experimental studies of the effect of pumping conditions on the spectral and temporal characteristics of IR Ar I laser radiation under excitation of the active medium by longitudinal pulsed inductive discharge are presented. The lasing was obtained at transitions of neutral argon atoms at wavelengths of 1213, 1240, 1270, 1694, and 1791 nm in pure argon and in its two-component mixtures with helium and neon. The optical pulse length at half maximum was (5 ± 1) ns. The radiation energy attained 0.1 mJ.

The experimental results of the lasing characteristics dependence of the inductive neon laser (λ = 540.1 nm) on the optical cavity quality factor are presented. In the described experiments, the laser was operated in the amplified spontaneous emission mode. A frontal-substrate resonator (made according to the type of an open Fabry–Perot interferometer) was used, as well as a dense resonator with a reflection coefficient of the front mirror of 82%. Replacing the front substrate with an output mirror resulted in an increase in the lasing energy and optical pulse duration from 8.5 μJ to 41 μJ and from 10.0 ± 0.1 ns to 14.8 ± 0.1 ns, respectively. It is shown that the use of a dense resonator allows us to change the shape of the laser beam in the far field from annular to circular and to obtain intensity distribution close to uniform.

In 2021, data on the effective pulsed gas discharge inductive CO2 laser with radio-frequency (RF) excitation were published with a pulse output energy of E∼ 1 J (the efficiency η∼ 14.5%) on the gas mixture He:N2:CO2 = 8:2:1. The efficiency of the developed CO2 laser had exceeded the value η∼ 21% at E∼ 350 mJ. At the beginning of 2022, it was shown that xenon addition (Xe = 4%) to the gas mixture made it possible to achieve an efficiency of η∼ 27% at an output energy of E∼ 600 mJ. For the first time, the effect of hydrogen additives in the active medium (He:N2:CO2:H2 and N2:CO2:H2 gas mixtures) was investigated for a pulsed inductive CO2 laser with RF excitation depending on the RF-pumping pulse duration value (τ), which allows the energy and temporal radiation characteristics of the laser to be controlled over a wider range. In addition to those already published, new experimental data have been obtained, namely the output beam profile of the inductive CO2 laser based on He:N2:CO2 = 8:2:1 gas mixture depending on the τ value. The new data will improve our understanding of inductive CO2 laser physics and of the plasma–chemical processes occurring in its active medium. RF current pulses propagated along inductor wires and, thus, an inductive discharge was formed to create a population inversion by IR transitions of CO2 * molecules.

For the first time, lasing on electronic transitions of neutral neon atoms (540.1, 594.4, and 614.3 nm) pumped by a pulsed inductive cylindrical discharge was obtained. Pure neon and its mixtures with NF3 and SF6 were used as active media. The optical pulses’ duration was 15 ± 2 ns (FWHM) at a wavelength of 540.1 nm and did not exceed 5 ± 1 ns (FWHM) at a wavelength of 614.3 nm. The maximum laser radiation energy was obtained at a wavelength of 540.1 nm and reached 50 μJ.

A 4.5 mJ energy of generation at a half-amplitude duration of 7 ± 1 ns (FWHM) with a pulse peak power of more than 600 kW is obtained for the first time with nitrogen pumped by a pulsed induction discharge. Laser generation is achieved in the form of a ring with a diameter of around 20 mm and a width of around 2 mm at wavelengths of 337.1 and 357.7 nm.

For the first time, laser radiation at transitions of neutral argon atoms pumped by a pulsed inductive discharge was obtained. The radiation consisted of spectral lines with wavelengths of 1.213 μm, 1.240 μm, 1.270 μm, 1.694 μm, 1.791 μm. Studies of the temporal characteristics of the radiation showed the duration of the optical pulses were 4 ± 1 ns (FWHM).

For the first time, when the nitrogen was pumped by a pulsed inductive discharge, generation energy of 11 mJ was obtained with pulse duration 10 ± 1 ns (FWHM). Pulse power exceeded 1 MW. The maximum value of the efficiency of the deposited energy was about 0.39%. Laser generation was obtained at two wavelengths of 337.1 and 357.7 nm.

For the first time, the UV inductive nitrogen laser was created with generation energy of 11 mJ and pulse duration 10 ± 1 ns (FWHM). Lasing was obtained on two lines with wavelengths of 337.1 and 357.7 nm. The generation energy distribution over the cross section had a shape of a ring with diameter and width of about 40 and 2 mm, respectively.

The creation of a compact emitter for an inductive nitrogen laser (λ = 337.1 nm) with the active medium pumped by a pulsed inductive longitudinal discharge of the transformer type is reported for the first time. In the inductive laser head created, the lasing energy attains 0.35 mJ and the lasing pulse length is (25 ± 5) ns (FWHM) depending on the cavity Q-factor. The use of a semiconfocal cavity provides for a near-Gaussian beam profile.

Results of experimental studies of the gas mixture (laser active medium) effect on the lasing energy and overall efficiency of excimer discharge ArF (193 nm), KrCl (222 nm) KrF (248 nm), and XeCl (308 nm) lasers operating in buffer-free gas mixtures are presented. The optimal (in terms of maximum radiation energy) ratios of the gas components of the excimer laser active media are found, at which efficient operation is achieved with a sufficiently high power of the laser radiation. It is confirmed experimentally that for the rare gas halide discharge pumped excimer lasers the presence of a buffer gas in the active medium is not required for efficient laser operation. For example, in two-component excimer laser gas mixtures, containing working rare and halogen-containing gases, laser pulse energy of up to 170 mJ and high pulsed power of laser radiation of up to 24 MW have been attained for the first time for pulsed gas-discharge excimer lasers operating on electronic transitions at excimer ArF*, KrCl*, KrF*, and XeCl* molecules pumped by a transverse electric volume discharge of a low-pressure buffer-free gas mixture. A overall efficiency maximum of up to 0.8% was experimentally attained for binary gas mixture of KrF and XeCl lasers.

For the first time, it has been reported that laser radiation is observed when pumping xenon-containing gas mixtures with a pulsed longitudinal inductive discharge of a transformer type. The lasing spectrum was recorded in the region of 190 ± 1150 nm and consisted of two lines 904.5 nm and 979.8 nm. The intensity ratio strongly depended on the pressure of the active medium.

We report the results of experimentally investigated dependences of temporal, spectral and spatial characteristics of an inductive HF-laser generation on the pump conditions. Gas mixtures H2 – F2(NF3 or SF66) and He(Ne) – H2 – F2(NF3 or SF6) were used as active media. The FWHM pulse duration reached 0.42 μs. This value corresponded to a pulsed power of 45 kW. For the first time, the emission spectrum of an inductive HF laser was investigated, which consisted of seven groups of bands with centres around the wavelengths of 2732, 2736, 2739, 2835, 2837, 2893 and 2913 nm. The cross section profile of the laser beam was a ring with a diameter of about 20 mm and width of about 5 mm. Parameters of laser operation in the repetitively pulsed regime were sufficiently stable. The amplitude instability of light pulses was no greater than 5% – 6%.

The paper presents the results of experimental measurements of the emission properties of water plasma in an inductive discharge. The power of the inductive discharge was 600 W at a frequency of 27 MHz and a pressure from 0.25 to 4 mbar. Plasma temperature was estimated from the Balmer hydrogen series using relative intensities method. It is shown that in this pressure range, the plasma is not in equilibrium and the energy difference between individual excited states increased with distance from the tube axis. The plasma heating time was estimated from the dynamics of the spectral line intensities to be 200 ms.

The investigation results for the possibility of a pulsed inductive cylindrical discharge as a new method of pumping gas lasers operating at different transitions of atoms and molecules with different mechanisms of formation of inversion population are presented.The excitation systems of a pulsed inductive cylindrical discharge(pulsed inductively coupled plasma) in the gases are developed and experimentally investigated.At the first time,four kinds of pulsed inductive lasers on the different transitions of atoms and molecules are created.Characteristic features of the emission of pulsed inductive lasers are ring-shaped laser beam with low divergence and pulse-to-pulse instability is within 1%.Firstly,the red laser on the electronic transitions of atomic fluorine(FI) pumped by a pulsed inductive cylindrical discharge is developed.Lasing at 8 wavelengths in the spectral area 624-755 nm is obtained by exciting He-F2(NF3,SF6) gas mixtures in a pressure range from 2.66-46.55 kPa.The energy of the FI laser is 2.6 mJ at pulse durations of 80 ns and the divergence is 0.4 mrad.Secondly,the far infrared laser on the vibrational-rotational transitions of CO2 molecules in the ground electronic state with a wavelength of 10.6 μm is created.The maximum energy of this inductive laser is 152 mJ at the pulse duration of 160 μs(FWHM).Thirdly,the pulsed inductive discharge H2 laser at the electronic transitions of hydrogen molecules in near IR laser is also developed.The laser action on four lines with 0.835 μm,0.89 μm,1.116 μm and 1.122 μm is obtained,and its pulsed peak power is 11 kW at duration of 20 ns.Furthermore,the pulsed inductive UV nitrogen laser on self-limited electronic transitions C3Πu→B3Πg at 337.1 nm and 357.7 nm is created,and its maximum generation energy is 4.5 mJ at low pressures 133 Pa and pulsed peak power is 300 kW at pulse duration(15±1) ns.The measured divergence of the inductive nitrogen laser radiation is 0.3 mrad.

Lasing at 337.1 and 357.7 nm is obtained upon excitation of nitrogen molecules by a toroidal pulsed inductive discharge. A system for formation of a pulsed inductive discharge for exciting gas lasers is described. The spontaneous emission spectra of the nitrogen inductive discharge plasma and the emission spectrum of the nitrogen laser are recorded and interpreted. The dependences of the energy and duration of laser pulses on the resonator Q factor and pump level are studied. The output energy of the inductive nitrogen laser emitting 15±1-ns pulses achieves 4.5 mJ. The generation of high-power 300-kW pulses is obtained for the first time at a low (~1 Torr) pressure of pure nitrogen. The spatial distribution of the laser radiation intensity in the discharge tube cross section is investigated. The cross section of the radiation beam of the inductive nitrogen laser had the shape of a ring with the external diameter of 34 mm and width ~4 mm, its divergence being ~0.8 mrad. The average output power of the laser achieved 120 mW at a pulse repetition rate of 30 Hz.

A pulsed inductive nitrogen laser with a wavelength of 337.1 nm and a pulse power of 200 kW has been created. The excitation system of a cylindrical pulsed inductive discharge in nitrogen has been described. The spectral, energy, and temporal parameters of laser radiation have been investigated. Pulses with an energy of 2.4 mJ and a duration of 12 ± 1 ns have been generated. Laser radiation has the ring shape with an external diameter of 33 mm and a thickness of 1–1.5 mm. The divergence of radiation is 0.3 mrad.

It is proposed to use a pulsed transverse inductive discharge for exciting gas lasers operating on electron transitions in atoms and molecules. An electron transition laser on fluorine (FI) atoms pumped by a transverse inductive discharge is developed. Lasing at three wavelengths (703.75, 712.79, and 731.1 nm) is obtained by exciting He-F2 (NF3) gas mixtures in a pressure range from 20 to 350 Torr. The results of experimental investigation of the spectral, temporal, and energy characteristics of the inductive FI laser are presented.

The emergence of Lewis-Rayleigh afterglow under conditions of UV laser radiation formation and absence of any IR lasing in nitrogen pumped by a pulsed inductive discharge is demonstrated. The dependence of Lewis-Rayleigh afterglow intensity on pumping conditions and the reasons of IR lasing absence in inductive discharge nitrogen laser are experimentally investigated. Keywords— pulsed inductive discharge; UV nitrogen laser, Lewis-Rayleigh afterglow, spectrum

The paper provides an overview of the results of multiyear joint researches of team of collaborators of Institute of Laser Physics SB RAS together with NF IRTC "Eye Microsurgery" for the period from 1988 to the present, in which were first proposed and experimentally realized laser medical technologies for correction of refractive errors of known today as LASIK, the treatment of ophthalmic herpes and open-angle glaucoma. It is proposed to carry out operations for the correction of refractive errors the use of UV excimer KrCl laser with a wavelength of 222 nm. The same laser emission is the most suitable for the treatment of ophthalmic herpes, because it has a high clinical effect, combined with many years of absence of recrudescence. A minimally invasive technique of glaucoma operations using excimer XeCl laser (λ=308 nm) is developed. Its wavelength allows perform all stages of glaucoma operations, while the laser head itself has high stability and lifetime, will significantly reduce operating costs, compared with other types of lasers.

This paper reports on the excitation of atomic spectra of tap water vapor using an inductive discharge. It is shown that at a RF source frequency of 27 MHz and a plasma power output from 500 to 600 W, a steady discharge exists to pressures of 10-2 atm. Plasma temperature was determined by the Boltzmann plot method and was approximately 5500 K. At this temperature, it was possible to detect sodium ions dissolved in water. This suggests that an inductive discharge in water vapor can be used to determine the presence of impurities.

Pulsed inductive discharge is a new alternative method of pumping active gas laser media. The work presents results of experimental investigations of near, mid, and far IR inductive gas lasers (H2, HF, and CO2) operating at different transitions of atoms and molecules with different mechanisms of formation of inversion population. The excitation systems of a pulsed inductive cylindrical discharge (pulsed inductively coupled plasma) and pulsed RF inductive discharge in the gases are developed. Various gas mixtures including H2, N2, He, Ne, F2, NF3, and SF6 are used. Characteristics of near IR H2 laser radiation are investigated. Maximal pulse peak power of 7 kW is achieved. The possibility of using a pulsed inductive discharge as a new method of pumping HF laser active medium is demonstrated. The pulsed RF inductive CO2 laser is created and a total efficiency of 17% is achieved.

For the first time, we have used a pulsed inductive discharge to initiate a chemical HF laser. This publication presents research into selection of an active medium for such a laser, as well as the composition of the gas mixture. For the mixture of H2?SF6 we have managed to obtain lasing in the infrared spectrum around 2.7??m. Addition of buffer gases such as either He or Ne, or both of them, has resulted in increased lasing energy. Experiments have been performed to study the timing and output performance characteristics of the chemical HF laser at different pressure and pumping levels. For the mixture with Ne at a pressure of 45?Torr, the energy obtained was 10?mJ, and the peak pulse power ?5?kW. The pulse duration (FWHM) was 2??s.

This paper presents a study of the optical properties of the components of the stroma of the human cornea in the wavelength range 190–250nm. It is shown that absorption of 223‐nm radiation by the corneal fluid is a factor of 20 less than of 193‐nm radiation. Because of this effect, the rate and efficiency of ablation of the cornea is about a factor 2 greater for laser radiation with a wavelength of 223nm than for 193‐nm radiation. The temperature on the surface of the cornea has been measured when radiation with wavelengths 193 and 223nm is acting on it. It was found that the relative temperature increase on the surface of the cornea during ablation by wavelength 193nm was 11°C, and during ablation at 223nm only 5°C for identical parameters of operation and laser radiation. It is shown that 223‐nm radiation is preferable for performing refractive operations, as having a number of advantages over the traditionally used 193‐nm radiation.