Gas Laser: Stimulated Emission and Positive Ions

[vin300]

In a gas laser, an electron in the highest energy state absorbs photon for stimulated emission to occur, but now since it has more energy than its highest state, shouldn't it escape the atom and the active medium be left only with positive ions?

 

[Claude Bile]

In a gas laser, an electron in the highest energy state absorbs photon for stimulated emission to occur, but now since it has more energy than its highest state, shouldn't it escape the atom and the active medium be left only with positive ions?

Nope. Atoms only become ionised when the absorbed energy exceeds the ionisation potential.

Claude.