Scaling of collisionally pumped 3shyphen;3plasers in the neon isoelectronic sequence

摘要

Population inversions between the 3pand 3slevels of neonlike ions with atomic numbersZ=14, 18, 22, 26, 32, and 36 have been calculated. The population inversions result from the preferential population of the 3plevel by electron collisional excitation from the ground configuration of the ion and occur over a wide range of electron temperature and electron density (from 1017cmminus;3for Sithinsp;V to 1022cmminus;3for Krthinsp;XXVII). For all ions that are studied, the maximum value of the population inversion (N3p/g3pminus;N3s/g3s) for the transition 3p1S0minus;3suP1(whereurepresents the upper of the singlet and triplet levels) is found to be approximately equal to 4times;10minus;3NI, whereNIis the total density of neonlike ions. With the exception of Sithinsp;V, laser gains greater than 1 cmminus;1are possible for all the ions that are considered, and the gain increases with atomic numberZ. For Sithinsp;V and lowerhyphen;Zions, electron collisional mixing of the upper and lower laser levels restricts the electron density at which the population inversion occurs and limits the laser gain to values less than 1 cmminus;1. The scaling of the laser gain and the plasma parameters with atomic numberZis presented. For an electron density of 1021cmminus;3, the optimum atomic numberZthat results in the highest gain on the 3p1S0minus;3suP1transition isZ=26 (Fethinsp;XVII), and the gain is equal to 30 cmminus;1.