Capillary discharges for guiding of laser pulses

The dynamics of a capillary discharge is studied to achieve optimum conditi ons for the guiding of ultrashort intense laser pulses. A dynamic regime is revealed in which, after a short transient process, the discharge plasma i s in dynamic and thermal equilibrium. Such plasma configuration is stable a gainst Mi-ID perturbations. It is shown that the radial inhomogeneity of th e discharge plasma composition can provide the improvement of the focusing properties of a plasma waveguide. The radius of the region where electromag netic radiation is localized is governed by a contact discontinuity between the plasma that initially fills the channel and the plasma that is produce d due to ablation of the capillary wall material. (C) 2000 MAIK "Nauka/Inte rperiodica".