Patent ID: 8658967

Claim:
A method for sustaining a plasma, comprising: providing a volume of a gas; generating illumination of a first selected wavelength; and forming a first plasma species in a first region of the gas and at least a second plasma species in at least a second region of the gas by focusing the illumination of the first selected wavelength into the volume of the gas, the first region having a first average temperature and a first size, the at least a second region having at least a second average temperature and at least a second size, the illumination of the first selected wavelength substantially transmitted by the at least a second plasma species, the illumination of the first selected wavelength substantially absorbed by the first plasma species by tuning the first selected wavelength of the illumination to an absorption line of the first plasma species, the absorption line being associated with at least one of an ionic absorption transition or an excited neutral transition of the first plasma species.