High-speed circuits for TE discharge lasers and high-voltage applications

Abstract

Self-heterodyne mixing method of two inter-mode beat frequencies for frequency stabilization of a three-mode He-Ne laser AIP Advances 2, 022170 (2012) Experimental investigation on focusing characteristics of a He-Ne laser using circular Fresnel zone plate for highprecision alignment of linear accelerators Rev. Sci. Instrum. 83, 053301 (2012) Study of laser plasma emission from doped targets Rev. Sci. Instrum. 83, 02B911 (2012) Analysis of temporal jitter in a copper vapor laser system Rev. Sci. Instrum. 83, 025105 (2012) Measurements and imaging of optical gain in optically pumped alkali-rare gas systems Appl. Phys. Lett. 100, 041110 (2012) Additional information on Rev. Sci. Instrum.Pulsed transverse electric (TE) glow discharges used to produce population inversions in gas lasers at l-20 atm require high-speed, high-voltage, high-current capacitor banks. In this article we first review and compare the circuits in common use to produce the required fast, self-sustained glow discharges in CO*, excimer, and N2 lasers. The parameters and circuit types given will be useful to future designers of pulsed gas lasers to design and to optimize any proposed circuit in order to yield any desired operating conditions and parameters. The n-stage circuit types presented are capacitor-transfer (C-C), L-C inversion, Marx bank, 'and fourfold L-C inversion, with their double-sided counterparts, and also their transmission-line counterparts, such as the Blumlein circuit. A one-parameter differential equation is developed which describes the general series C-L-R circuit. Electrical pulses measured on various lasers are compared with the differential equation solutions for various bank impedances and load resistances. We then present the design and measurements of a new automatically preionized, double-sided, L-C inversion circuit for an 8OO-mJ, TE CO2 laser, and compare it to previous systems. Methods to lengthen the discharge pulse, and some novel active mode locking techniques are discussed. We compare the L-C inversion circuit, the fourfold L-C inversion circuit, the conventional Marx bank, and the "double Marx bank" for lasers and other applications, such as pulsed particle accelerators. Finally, we discuss capacitor bank interconnections, electro-optic probe systems, and various triggering methods.

The effect of voltage pulse polarity on the performance of a sliding discharge pumped HF laser

“…The inductance of the inversion circuit main loop was L m = 40 nH and the corresponding value for the switching loop was L s = 35 nH. These values were calculated from the self ringing frequency of the corresponding loops under short circuiting of the electrode gap [8] and also by using the well known solenoid approximation formula [9].…”

Modelling of short-pulse generation in rare-gas halide excimer lasers I. The model and its verification

“…As in the system with the EOD, transmission of the acousto-optic modulator, and thereby the cavity losses, is modulated in this case in time with the variations in the voltage driving the acousto-optic cell. At moderate powers of the signal modulating the acousto-optic cell and su ciently narrow de¯ection angles of the EOD, the temporal trace of transmission for both types of modulator can be similar [45,46]. In addition, by adequate selection of the EOD maximum de¯ection angle (the amplitude of the driving voltage), one can obtain the same e ective width of the transmission window for both modulators; the width is the most important parameter of the modulator from the viewpoint of short-pulse generation.…”

“…powers of the modulating signals [45,46]; the condition is usually ful®lled in the laser with mode locking accomplished by means of an acousto-optic modulator. The acousto-optic modulator (`mode locker') can be treated as a kind of de¯ector in which the change (de¯ection) in the propagation direction of the beam occurs as a result of di raction on a di raction grating created in the medium by an acoustic wave generated with an electric signal.…”

A compact low inductance pulse energy driver system for pulse power applications

“…The FDM is a low inductance compound capacitor that facilitates easy integration of a 2-stage LC-inversion circuit. In particular, LC-inversion circuits provide a number of features such as fast-discharge, low inductance, and voltage multiplication [3]. When multiple units of FDM's are used in a scalable array, referred to here as a Pulse Energy Driver System (PEDS), this system provides a useful and versatile fast discharge pulsed power system by being able to produce a large amount of current over a short time span, and at the same time is relatively easy to handle by using manageable charging voltages of less than 40 kV.…”