The mono-module disk laser concept is an effective design for diode-pumped solid-state lasers, which allows the realization of lasers with super-high output power, having very good efficiency and also excellent beam q...The mono-module disk laser concept is an effective design for diode-pumped solid-state lasers, which allows the realization of lasers with super-high output power, having very good efficiency and also excellent beam quality. Since the first demonstration of the principle in 1964 the output power of mono-module disk has been increased to the level of few kW in continuous wave (CW) mode of operation. “Zig-Zag” disk laser geometry does not look like as a perspective one for further output parameters growing. The scaling laws for mono-module disk laser design show that the limits for CW mode of operation are far beyond 100 kW for output power and the energy can be higher than 100 J in pulsed mode of operation. Due to the efficient porous cooling technology and possibility of amplified spontaneous emission (ASE) suppression the operation of the mono-module disk laser geometry is possible in CW and pulse-periodical (P-P) modes at extremely high output power.展开更多
Laser spark obtained by using a conical optics is much more appropriate to form conducting channels in atmosphere.Only two types of lasers are actively considered to be used in forming high-conductivity channels in at...Laser spark obtained by using a conical optics is much more appropriate to form conducting channels in atmosphere.Only two types of lasers are actively considered to be used in forming high-conductivity channels in atmosphere,controlled by laser spark:pulsed sub-microsecond gas and chemical lasers(CO2,DF(deuterium fluoride)),short pulse solid-state and UV(ultraviolet)lasers.Main advantage of short pulse lasers is their ability in forming of super long ionized channels with a characteristic diameter of-100 mm in atmosphere along the beam propagation direction.At estimated electron densities below 1,016 cm3 in these filaments and laser wavelengths in the range of 0.5-1.0 mm,the plasma barely absorbs laser radiation.In this case,the length of the track composed of many filaments is determined by the laser intensity and may reach many kilometers at a femtosecond pulse energy of-100 mJ.However,these lasers could not be used to form high-conductivity long channels in atmosphere.The ohmic resistance of this type a conducting channels turned out to be very high,and the gas in the channels could not be strongly heated(〈1 J).An electric breakdown controlled by radiation of femtosecond solid-state laser was implemented in only at a length of 3 m with a voltage of 2 MV across the discharge gap(670 kV/m).Not so long ago scientific group from P.N.Lebedev physical institute has improved that result,the discharge gap(-1m)had been broken under KrF laser irradiation when switching high-voltage(up to 390 kV/m)electric discharge by 100-ns UV pulses.Our previous result-16 m long conducting channel controlled by a laser spark at the voltage-3 MV was obtained more than 20 years ago in Russia and Japan by using pulsed CO2 laser with energy-0.5 kJ.An average electric field strength was〈190 kV/m.It is still too much for efficient applications.展开更多
文摘The mono-module disk laser concept is an effective design for diode-pumped solid-state lasers, which allows the realization of lasers with super-high output power, having very good efficiency and also excellent beam quality. Since the first demonstration of the principle in 1964 the output power of mono-module disk has been increased to the level of few kW in continuous wave (CW) mode of operation. “Zig-Zag” disk laser geometry does not look like as a perspective one for further output parameters growing. The scaling laws for mono-module disk laser design show that the limits for CW mode of operation are far beyond 100 kW for output power and the energy can be higher than 100 J in pulsed mode of operation. Due to the efficient porous cooling technology and possibility of amplified spontaneous emission (ASE) suppression the operation of the mono-module disk laser geometry is possible in CW and pulse-periodical (P-P) modes at extremely high output power.
文摘Laser spark obtained by using a conical optics is much more appropriate to form conducting channels in atmosphere.Only two types of lasers are actively considered to be used in forming high-conductivity channels in atmosphere,controlled by laser spark:pulsed sub-microsecond gas and chemical lasers(CO2,DF(deuterium fluoride)),short pulse solid-state and UV(ultraviolet)lasers.Main advantage of short pulse lasers is their ability in forming of super long ionized channels with a characteristic diameter of-100 mm in atmosphere along the beam propagation direction.At estimated electron densities below 1,016 cm3 in these filaments and laser wavelengths in the range of 0.5-1.0 mm,the plasma barely absorbs laser radiation.In this case,the length of the track composed of many filaments is determined by the laser intensity and may reach many kilometers at a femtosecond pulse energy of-100 mJ.However,these lasers could not be used to form high-conductivity long channels in atmosphere.The ohmic resistance of this type a conducting channels turned out to be very high,and the gas in the channels could not be strongly heated(〈1 J).An electric breakdown controlled by radiation of femtosecond solid-state laser was implemented in only at a length of 3 m with a voltage of 2 MV across the discharge gap(670 kV/m).Not so long ago scientific group from P.N.Lebedev physical institute has improved that result,the discharge gap(-1m)had been broken under KrF laser irradiation when switching high-voltage(up to 390 kV/m)electric discharge by 100-ns UV pulses.Our previous result-16 m long conducting channel controlled by a laser spark at the voltage-3 MV was obtained more than 20 years ago in Russia and Japan by using pulsed CO2 laser with energy-0.5 kJ.An average electric field strength was〈190 kV/m.It is still too much for efficient applications.
