STABLE RELATIVISTIC CHARGE-DISPLACEMENT CHANNELS IN ULTRAHIGH POWER-DENSITY (APPROXIMATE-TO-10(21) W/CM(3)) PLASMAS/

Robust stability is a chief characteristic of relativistic/charge-disp lacement self-channeling. Theoretical analysis of the dynamics of this stability (i) reveals a leading role for the eigenmodes in the develo pment of stable channels, (ii) suggests a technique using a simple lon gitudinal gradient in the electron density to extend the zone of stabi lity into the high electron density/high power density regime, (iii) i ndicates that a situation approaching unconditional stability can be a chieved, (iv) demonstrates the efficacy of the stable dynamics in trap ping severely perturbed beams in single uniform channels, and (v) pred icts that approximate to 10(4) critical powers can be trapped in a sin gle stable channel. The scaling of the maximum power density with the propagating wavelength lambda is shown to be proportional to lambda(-4 )or a given propagating power and a fixed ratio of the electron plasma density to the critical plasma density. An estimate of the maximum po wer density that can be achieved in these channels with a power of app roximate to 2 TW at a UV (248 nm) wavelength gives a value of approxim ate to 10(21) W/cm(3) with a corresponding atomic specific magnitude o f approximate to 60 W/atom. The characteristic intensity propagating i n the channel under these conditions exceeds 10(21) W/cm(2).