RU2354019C1 - Active medium for electric discharge co laser or amplifier and method of its pumping - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: active medium for electric-discharge CO laser or amplifier based on gas mixtures contains operating gas CO, buffer gases He or Ar, as well as added two-atom gases. Molecules of added two-atom gases have energy of vibrational transition 0→1 of ground electronic state less than 1800 cm^-1, their quantity constituting from 0.2 to 80 relative to quantity of CO molecules. Method of pumping active medium with gas mixture by pulse electric discharge is characterised by the following: pumping is carried out with given specific put-in energy being in range from 0.01 to 1.5 J/(cm³ *Amaga) and duration of discharge pulse t being in range from 10 to 1000 mcs. Active medium for electric-discharge CO laser or amplifier based on gas mixtures is cooled to cryogenic temperatures (from 80 to 150 K) and is placed into CO laser or amplifier, operating in sealed off mode.

EFFECT: increase of power and efficiency of electric-discharge CO lasers and amplifiers operating on both main and overtone transitions, creation of powerful compact electric-discharge CO laser.

9 cl, 7 dwg

Description

The invention relates to laser physics and can be used to increase the power and efficiency of generating electric discharge CO lasers, as well as to create a powerful compact electric discharge CO laser or infrared radiation amplifier.

In CO lasers with the active medium pumped with a direct current electric discharge both at room temperature of the gas mixture [1, 2] and when it is cooled with liquid nitrogen [3] or using supersonic expansion [4], small oxygen additives are used (less than 10% of concentration of CO molecules), which prevent the decomposition of CO molecules as a result of plasma-chemical reactions occurring in a direct current discharge.

In contrast to CO lasers with active-medium pumping by a direct current discharge, plasma-chemical reactions in electroionization CO lasers and amplifiers occur mainly in a very thin cathode layer; therefore, their contribution to the kinetic processes occurring in the bulk of the laser active medium is negligible [5]. In this regard, oxygen-free mixtures are used in electroionization CO lasers [6, 7]. The gradual degradation of the gas mixture can occur only in a closed-cycle electroionization CO laser system, which has been operating continuously or in a pulse-periodic mode for a long time. However, in this case, it is sufficient to provide for regular replenishment of the loss of CO molecules and the removal of CO ₂ and C ₂ molecules. For example, in a closed-cycle cryogenic continuous technological electroionization CO laser [8], CO ₂ is removed in a heat exchanger cooled by liquid nitrogen.

In a sealed-off (without gas pumping) CO laser at room temperature, excited by a direct current discharge, the addition of oxygen reduces the radiation power [9]. This is due to the fact that, as a result of plasma-chemical reactions, CO ₂ molecules are formed in the discharge, which are not removed from the discharge region, unlike CO lasers with pumping of the active medium. Since CO and CO ₂ molecules efficiently exchange vibrational energy, the appearance of CO ₂ molecules in the active medium leads to the resettlement of excited vibrational levels of the CO molecule. Therefore, in the proposed sealed-off CO laser with a gas mixture N ₂ : Xe: CO: He: O ₂ = 1.1: 2.0: 2.4: 27.0: 0.06, the mixture is replaced every 10 minutes of operation, which causes additional difficulties.

There are CO lasers pumped by a high-frequency (HF) discharge, both water-cooled [10] and cryogenic [11], in which gas mixtures with a small (up to 5% of the CO concentration) oxygen additive are used. In [10], a vertical arrangement of flat electrodes was used for the most convenient replacement of metal inserts in them, because The purpose of these studies was to study the effect of electrode materials on the degradation of a gas mixture during laser operation.

Closest to the proposed invention is the active medium of an electric-discharge CO laser and its pumping method, described in [12]. The active medium consisted of a gas mixture of the following composition He: N ₂ : CO: O ₂ = 78.8: 16: 5: 0.2. The pulsed pumping method was implemented by modulating the RF power with a carrier frequency F = 13.56 MHz with a low frequency Fnch from 100 Hz to 10 kHz. In this case, the pulse duration t of a rectangular shape was more than 1000 μs, and the duty cycle, i.e. the ratio t / T ₀ , where T ₀ = 1 / Fnch, was 0.5 in all experiments. However, it should be noted that, despite the use of two heat exchangers, the design of this laser did not allow lowering the temperature of the active medium below room temperature, which did not provide an effective operating mode of the CO laser. In addition, the authors of this laser could not achieve the compactness of their device (the length of the active medium was ~ 1 m), because the closed laser operation cycle implemented in [12] required additional large-scale equipment.

The technical task of the proposed invention is to increase the power and efficiency (efficiency) of electric-discharge CO lasers and amplifiers operating both at the main (radiation wavelength from 4.7 to 8.2 μm) and overtone (radiation wavelength from 2.5 to 4.2 μm) transitions, and also the creation of a powerful compact electric-discharge CO laser.

According to the invention, the stated technical problem is solved by adding gas mixtures of CO: He (Ar), CO: N ₂ , CO: N ₂ : He (Ar) diatomic molecules with the energy E ₀₁ of the 0 → 1 vibrational transition to the traditionally used in electric-discharge CO lasers. the ground electronic state is less than 1800 cm ^-1 , in an amount of 0.2 to 80 relative to the concentration of CO molecules. Such an additive may be, for example, oxygen, in which E ₀₁ = 1556 cm ^-1 . Air can be used as an oxygen source, then the ratio CO: Air = 1: X is observed in the active medium, where X is in the range from 1 to 120.

According to the invention, a method for pumping an active medium with the gas mixture described above is carried out by a pulsed discharge at a given specific energy input in the range of 0.01 to 1.5 J / (cm ³ · Amaga) and the duration of the discharge pulse in the range from 10 to 1000 μs (Amaga - unit of relative gas concentration, numerically equal to the number of moles in the molar volume (22.4 l)). The pulse pumping method can be implemented by modulating the RF power with a carrier frequency F lying in the range from 10 to 150 MHz, low frequency F _{low frequency} lying in the range from 0.1 to 25 kHz.

According to the invention, the structure of the envelope of the RF excitation pulse is such that a prepulse follows, which provides ignition of the discharge in the working mixture. The amplitude of the prepulse P _imp in power is in the range from P _pzh , the power at which the discharge is ignited, to the maximum peak power of the RF generator P _max . The prepulse is followed by the main pump pulse of duration t. In this case, the average rf power supplied to the discharge gap can vary when pumped by the main pulses as their duty cycle, i.e. the ratio t / T _{0 is} from 0.1 to 1.0, where T ₀ = 1 / F _LF is the modulation period, t is the duration of the modulating pulse, and the instantaneous amplitude of the RF power P is from 0.1 to 1.0 of the value of P _max . Also, pumping can be carried out exclusively by prepulses, while their duration varies in the range from 0.01 to 0.1 from the modulation period T ₀ , and their amplitude - from P _pod to P _max .

According to the invention, the active medium pumping method described above can be implemented in such a way that the plane perpendicular to the direction of the electric field of the high-frequency discharge is oriented vertically, and the discharge zone is not limited by anything from above and below. The described active medium excited by this pumping method is cooled to cryogenic temperatures (from 80 to 150 K) and placed in a CO laser or amplifier operating in a sealed mode.

Figure 1 shows the dynamics of the gain G in a pulsed CO amplifier at the transition 10 → 9 P (15) in a mixture of CO: He: O ₂ = 1: 4X for four values of X.

Figure 2 shows the dependence of the maximum gain G _max on the vibrational quantum number V in a mixture of CO: He: O ₂ = 1: 4: X for six values of X.

Figure 3 presents the energy of the vibrational transitions of the molecules of oxygen, nitrogen and carbon monoxide.

Figure 4 shows the dependence of the efficiency of the electroionization CO laser on the average specific energy input Q _in for mixtures with different proportions X of oxygen molecules with respect to CO molecules in a CO: He: O ₂ = 1: 4: X gas mixture.

Figure 5 shows the dependence of the efficiency (COP) of a CO laser on the local specific energy input Q _in for two gas mixtures of CO: O ₂ : Ar = 1: 10: 10 and CO: N ₂ : Ar = 1: 10: 10.

Figure 6 shows the structure of the envelope of the pulse of the RF excitation of the CO laser.

Figure 7 presents a diagram of a compact slit CO laser with RF excitation.

The temporal dynamics of the gain at the vibrational-rotational transitions V → V-1 P (J) (V is the number of the vibrational level, J is the number of the rotational sublevel) of the ground electronic state of the CO molecule in the active medium of a pulsed CO laser are determined by the kinetic processes of vibrational exchange between the molecules. During pulsed pumping, the lowest (V, W≤8) vibrational levels of the CO molecule are populated. The population of higher levels occurs in the process of vibrational-vibrational exchange between CO molecules

Adding oxygen to the gas mixture leads to a substantial change in the dynamics of the gain of a pulsed electric-discharge CO laser. For high transitions (from the band 19 → 18 and above), the addition of oxygen leads to a decrease in the gain and to a decrease in the lifetime of the inverse population, i.e. time during which G> 0. At low vibrational-rotational transitions (from the band 7 → 6 to 14 → 13), the picture changes to the exact opposite: when oxygen is added, the gain increases.

The dynamics of the gain for low transitions is presented on the example of the transition 10 → 9 P (15) at four values of X, where X is the oxygen fraction in the mixture CO: He: O ₂ = 1: 4: X (see Figure 1). At the transition 10 → 9 P (15) with increasing X, the maximum value of the gain G _max increases. Moreover, at X = 2.0, the value of G _max is eight times greater than for a mixture without oxygen (X = 0).

For vibrational-rotational transitions in the range of bands from 15 → 14 to 18 → 17 with small additions of O ₂ molecules (A = 0.02-0.07), the value of G _max increases, then for X> 0.01 it decreases, and for values large X = 1.0 , observed mainly absorption.

More clearly the effect of oxygen additives on the maximum value of the gain, which is realized at various transitions, is shown in FIG. 2, which shows the dependence of G _max on the vibrational quantum number V in a mixture of CO: He: O ₂ = 1: 4: X for six values of X From Figure 2 it can be seen that even with small values of X (up to 0.2), the value of G _max decreases sharply at high transitions. And at low transitions, an increase in the oxygen fraction in the mixture leads to an increase in the maximum value of the gain G _max . At X = 2.0 G _max reaches 3.8 m ^-1 at the transition 10 → 9 P (15).

The observed change in the dynamics of the gain with the addition of oxygen is associated with the process of intermolecular vibrational exchange between CO and O ₂ molecules

where ΔE _VJ is the energy difference of the quanta of vibrational-rotational transitions of the molecules involved in the exchange.

The exchange rate (2) increases with increasing vibrational number V, because the quantum energy of vibrational-rotational transitions of the CO molecule at V ~ 20 is compared with the quantum energy of the O ₂ molecule in the band of the 0 → 1 vibrational transition equal to 1556 cm ^-1 . The increase in G _max (see Figure 2) at low transitions is due to the fact that, as a result of the exchange (2), the vibrational level V and the level V-1 are populated, i.e. intermolecular exchange (2) contributes to an increase in population at vibrational levels located below those that are effectively involved in such an exchange.

In addition to CO: He: O ₂ mixtures, the effect of oxygen additives on the dynamics of the gain is also observed in CO: N ₂ : O ₂ mixtures = 1: 9: X. With increasing X, the maximum gain G _max at the transition 10 → 9 P (15) also increases. Moreover, at X = 2.0, the value of G _max is two times greater than for a mixture without oxygen (X = 0).

In figure 3. The energies of vibrational transitions of oxygen, nitrogen, and carbon monoxide molecules are presented, calculated taking into account the values of the vibrational quantum energy 0 → 1 and the anharmanism constant of these molecules. In addition, figure 3 shows the possible channels of intermolecular exchange in an active medium containing these gases. In a CO mixture, traditional for a CO laser, a CO: N ₂ = 1: 9 mixture and other nitrogen-containing mixtures, both CO and N ₂ molecules are excited by a discharge. In this case, the vibrational energy stored in nitrogen is effectively transferred to the levels of CO molecules with V from 0 to about 10 through the process

.

.

This process strongly affects the formation of the vibrational distribution function of CO molecules, playing the role of additional pumping. In the case when oxygen is added to such a laser mixture, the process of intermolecular exchange (2) through high (V≥20) excited levels begins to influence the formation of the vibrational distribution function of CO molecules (see Figure 3). But due to the vibrational exchange (1) between the CO molecules, the presence of oxygen in the mixture also affects the vibrational distribution function for low V.

The inventors studied laser generation at the main transitions of the CO molecule in the CO: He: O _{2 =} 1: 4: X gas mixture depending on the oxygen content X. Figure 4 shows the dependence of the efficiency of the electroionization CO laser on the average specific energy input Q _in mixtures with different proportions X of oxygen molecules relative to CO molecules. When analyzing the results of the experiments presented in Figure 4, it is seen that with an increase in the oxygen fraction, the threshold value of the specific energy input decreases, i.e. Q _in , at which generation appears. However, the maximum specific energy input (energy input, above which the discharge becomes unstable and breakdown of the discharge gap develops) with an increase in the oxygen fraction decreased from 300 to 120 J / l Amag. The maximum value of the laser efficiency increases with increasing X, while the maximum value of the efficiency is achieved with a lower specific energy input. With equal specific energy inputs (for example, Q _in = 110 J / l Amag), the efficiency for a mixture with A = 4.0 reaches 27%, while for a mixture with X = 0 it is 8%.

In order to stabilize the discharge at high specific energy input, argon is used instead of helium. Figure 5 presents the dependence of the efficiency (COP) of a CO laser on the specific energy input Q _in for two gas mixtures of CO: O ₂ : Ar = 1: 10: 10 and CO: N ₂ : Ar = 1: 10: 10. Figure 5 shows that the use of argon can increase the maximum specific energy input up to 280 J / l Amag.

The efficiency of a CO laser on a CO: O ₂ : Ar = 1: 10: 10 mixture (i.e., at X = 10) reaches 47% of the input energy and is 1.6 times higher than the efficiency in a CO laser (30%) on a CO mixture : N ₂ : Ar = 1: 10: 10, and the ratio between the values of the laser efficiency reaches ~ 2.5 at Q _in = 100 J l ^-1 Amag ^-1 . The decrease in the efficiency of a CO laser on a CO: O ₂ : Ar mixture at Q _in > 170 J l ^-1 Amag ^-1 can be associated both with heating of the gas mixture and with the excitation of electronic states of oxygen.

The increase in the proportion of oxygen according to the authors of the invention is advisable up to L = 80, at large values, the processes of excitation of electronic states of oxygen begin to prevail [13], and the fraction of the discharge energy spent on the excitation of CO molecules decreases. Increasing the gain, power, and efficiency of an electric-discharge CO laser with high oxygen content in gas mixtures opens up the possibility of using air mixtures. In this case, in the active medium of the electric-discharge CO laser, a CO gas mixture should be used: Air = 1: X, where X is in the range from 1 to 120.

To increase the gain, and therefore the power and efficiency of an electric-discharge CO laser, not only oxygen, but also molecules of other diatomic gases can be added to its active medium. The main thing is that the energy of the 0 → 1 vibrational transition of the ground electronic state E _{01 of} these molecules is less than 1800 cm ^-1 . Then the process of intermolecular vibrational exchange of type (2) between these molecules and CO molecules will work, as a result of which the population of excited CO molecules will increase at working laser levels.

An increase in the gain is of great importance not only for large, but also for compact CO lasers, which can be used as tools for solving various scientific and applied problems. The above results allow, while maintaining the same energy characteristics, to reduce the size of the laser emitter or to increase the laser power with the same dimensions. The use of RF pumping in CO lasers in combination with cryogenic cooling [11] allows one to obtain the best power / dimensions ratio compared to CO lasers pumped by other types of electric discharge (electroionization, direct current, etc.).

Modulation of the RF excitation power (carrier frequency F is in the range from 10 to 150 MHz) with a low frequency F _LF lying in the range from 0.1 to 25 kHz allows one to organize the pumping of a CO laser, combining the advantages of a transverse RF discharge over a longitudinal independent discharge with the advantages pulsed pumping mode before continuous. The structure of the envelope of the RF excitation pulse supplied to the laser electrodes (see Fig. 6) is such that a prepulse follows, which ensures ignition of the discharge in the working mixture. The amplitude of the prepulse P _imp in power is in the range from P _{to the} power at which the discharge is ignited, to the maximum peak power of the RF generator P _max . The prepulse is followed by the main pump pulse of duration t. In this case, the average rf power supplied to the discharge gap can vary when pumped by the main pulses as their duty cycle, i.e. the ratio t / T ₀ from 0.1 to 1.0, where T ₀ = 1 / F _LF is the modulation period, and the instantaneous amplitude of the RF power P, component from 0.1 to 1.0 of the value

P _max . Also, pumping can be carried out exclusively by prepulses, while their duration τ varies in the range from 0.01 to 0.1 of the modulation period T ₀ , and their amplitude - from P _pod to P _max .

As experiments performed by the inventors have shown, it is necessary that the CO laser be pumped by pulses with a duration t ranging from 10 to 1000 μs, selected depending on the composition of the mixture (in particular, on the fraction of oxygen X). In this case, the value of the reduced specific energy input for each pulse should be in the range from 0.01 to 1.5 J / (cm ³ · Amag). To realize the operation of a CO laser in the regime with maximum efficiency, it is necessary to use RF pumping with short powerful pulses or exclusively prepulses. At the same time, to implement the regime of generation of a CO laser with the highest average power, it is necessary to use the longest main pulses in combination with the shortest prepulses, which allow maintaining stable burning of the RF discharge.

7. The scheme of a compact slot-hole CO laser with RF excitation is presented. The electrode system is located inside the laser chamber 1 and consists of two cooled hollow metal electrodes 2 through which refrigerant 3 is continuously pumped. Due to this, the electrodes can be cooled to a temperature of ~ 120 K (in the case of liquid nitrogen). The electrode system is oriented in such a way that the plane perpendicular to the direction of the electric field 4 of the high-frequency discharge is oriented vertically. Due to this orientation of the discharge zone, the gas mixture is automatically replaced from the discharge zone to fresh from the ballast volume of the laser chamber due to convection of the gas mixture heated in the discharge. Due to this, the molecules formed as a result of plasma-chemical reactions in the discharge zone (for example, СО ₂ , С ₂ О, CN, О ₃ , etc.) are deposited on the outer sides of cold electrodes. Thus, in the discharge zone, the concentration is reduced, including of those molecules that can take vibrational energy from CO molecules.

In addition, such a geometry of the discharge zone allows one to get rid of the accumulation of explosive amounts of liquid ozone and to carry out a sealed-off mode of operation of the cryogenic CO laser. The formation of liquid ozone occurs in cryogenic pumped CO lasers even with small additions of oxygen [14], which was apparently the reason why the soldered cryogenic CO laser has not yet been created.

The electric discharge is supported by the RF generator 5 with a matching system 6 of the load impedance and the output impedance of the RF generator. The laser cavity consists of a “dead” mirror 7 and an output mirror 8.

The proposed active medium for an electric-discharge CO laser and a method for pumping it were implemented in two versions.

Example 1. A cryogenic pulsed electroionization laser system with a discharge volume of 18 liters and an active medium length of 1.2 m was used. Ionization of the gas mixture was carried out by an electron beam. A direct-heating thermionic cathode was used as an electron source in an electroionization laser installation. The value of the accelerating voltage supplied to the thermal cathode was ~ 120 kV. The vacuum chamber of the electron gun was separated from the laser cell by a separation foil (polyimide film ~ 40 μm thick). A non-self-sustained volume discharge developed between the grid cathode and the solid copper anode spaced 10 cm apart.The pulse duration of the electroionization discharge was determined by the duration of the electron beam current pulse, which could vary in the range from 25 to 1500 μs by changing the parameters of the electron gun. In various experiments, the density of the working gas mixture in the laser cell was from 0.04 to 0.3 Amag. The double walls of the laser cell formed the so-called “nitrogen jacket”, which was filled with liquid nitrogen, which allowed cooling the gas mixture to ~ 100 K. The laser resonator ~ 3.5 m long was external and consisted of a spherical copper mirror (radius of curvature 10 m) and flat output mirror (transmittance ~ 50% in the wavelength range 4.5-6.5 microns). To obtain lasing on the first overtone of CO molecules, we used a cavity of ~ 2.5 m in length from spherical and planar mirrors with a transmittance of ~ 1% in the wavelength range of 2.6-3.0 μm, mounted directly on a laser cell (internal resonator). Various gas mixtures were used, in particular, CO: He: O ₂ = 1: 4: X, CO: N ₂ : O ₂ = 1: 9: X, where X is the oxygen fraction in the mixture ranged from 1 to 4.0, CO : O ₂ : Ar = 1: 10: 10, CO: N ₂ : Ar = 1: 10: 10, CO: Air.

Example 2. A cryogenic slotted CO laser with RF excitation consisted of two main parts: a laser chamber inside which there was an electrode system and a laser resonator, and an RF generator with a system for matching the load impedance and output impedance of the RF generator.

There were openings on the side walls of the laser chamber with flanges for connecting a vacuum pumping system, a gas mixture component inlet system, liquid nitrogen supply and drain pipes (separately for each of the two electrodes), and current leads for supplying RF voltage to the electrodes. Optical windows for outputting laser radiation and alignment devices were located on the end walls of the chamber, providing remote adjustment of the cavity mirrors located inside the chamber.

The installation electrode system consisted of two cooled hollow brass electrodes through which liquid nitrogen was continuously pumped. Due to this, the electrodes were cooled to a temperature of ~ 120 K. The length of the electrodes along the axis of the laser cavity was 250 mm. The height of the discharge gap was 30 mm. The working surfaces of the electrodes were polished to a mirror finish. The electrodes were fixed on a massive metal base using three dielectric holders with adjusting screws, which allowed changing the size of the discharge gap between them from 2 to 4 mm, as a result of which it was possible to vary the pump parameters (input power per unit volume of the AC).

To excite the discharge, a high-frequency generator with a maximum output power in the continuous mode P _max = 500 W with a carrier frequency F = 81.36 MHz was used. The generator could work in a pulse-periodic mode with low-frequency (F _LF = 0.1-25 kHz) amplitude modulation of the output RF power. The structure of the pulse supplied by the generator to the laser electrodes is shown in Fig.6.

The laser cavity with a length of 270 mm consisted of a “blind” spherical (radius of curvature 1.5 m) mirror and a translucent flat output mirror with a reflection coefficient (85 ± 5)% in the wavelength range of 5.0–5.5 μm. Gas mixtures of CO: N ₂ : O ₂ : He: Xe, CO: He: Xe: Air with different component ratios were used. The total pressure in the laser chamber ranged from 10 to 100 Torr. When the electrodes were cooled with liquid nitrogen, the CO laser operated in a sealed mode, i.e. without changing the working mixture, within 12 hours without reducing the average power.

The proposed active medium for an electric-discharge CO laser or amplifier and its pumping method allow increasing the gain at the working laser transitions to ~ 4 m ^-1 , bringing the laser efficiency to ~ 50% and creating a powerful compact CO laser or infrared amplifier operating in sealed off mode at cryogenic temperatures.

Bibliography

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Claims (9)

1. An active medium for an electric-discharge CO laser or amplifier based on gas mixtures containing CO working gas, He or Ar buffer gases, and also added diatomic gases, characterized in that the molecules of the added diatomic gases have a vibrational transition energy 0 → 1 of the main electronic states less than 1800 cm ^-1 , while their number is from 0.2 to 80 relative to the number of CO molecules. 2. The active medium according to claim 1, characterized in that oxygen is used as an additive. 3. The active medium according to claim 2, characterized in that air is used as an oxygen source in such a way that the ratio CO: Air = 1: X is observed, where X is in the range from 1 to 120. 4. The method of pumping an active medium with a gas mixture according to any one of claims 1 to 3 by a pulsed electric discharge, characterized in that the pumping is carried out at a reduced specific energy input in the range from 0.01 to 1.5 J / (cm ³ · Amag) and the duration of the discharge pulse t, which is in the range from 10 to 1000 μs. 5. The method of pumping the active medium according to claim 4, in which the pump is carried out by a high-frequency (HF) discharge, characterized in that the HF discharge is modulated in time by a low frequency F _LF lying in the range from 0.1 to 25 kHz. 6. The method of pumping the active medium according to claim 5, characterized in that the envelope structure of the RF excitation pulse supplied to the laser electrodes is such that a prepulse follows, with a duration in the range from 0.01 to 0.1 of the modulation period T ₀ = 1 / F _LF , for ignition of a discharge in the working mixture, the amplitude of which in power is in the range from P _pn - the power at which the discharge is ignited to the maximum peak power of the RF generator P _max , and after it the main pump pulse of duration t. 7. The method of pumping the active medium according to claim 6, characterized in that the average RF power supplied to the discharge gap varies when pumped by the main pulses as their duty cycle, i.e. the ratio t / T0 from 0.1 to 1.0, and the instantaneous amplitude of the RF power, component from 0.1 to 1.0 of the value of P _max . 8. The method of pumping the active medium according to any one of claims 5 to 7, characterized in that the plane perpendicular to the direction of the electric field of the high-frequency discharge is oriented vertically, and the discharge zone is not limited to above and below. 9. The active medium for an electric-discharge CO laser or amplifier based on gas mixtures, characterized in that the active medium is made according to any one of claims 1 to 3 and is pumped by the method of claim 8, while it is cooled to cryogenic temperatures (from 80 to 150 K) and placed in a CO laser or amplifier operating in sealed mode.

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