These devices function when more molecules exist in higher energy states than lower energy ones, called population inversion.
These devices cannot be created from two-level systems because the upward and downward transitions occur at equal rates, a result explained by Einstein's A and B coefficients. These devices function when more molecules exist in higher energy states than lower energy ones, called population inversion. The helium-neon type of these devices produces 543-, 633-, or 1150-nanometer light. For 10 points, name these devices that produce coherent beams of light from the stimulated emission of radiation.
These devices cannot be created from two-level systems because the upward and downward transitions occur at equal rates, a result explained by Einstein's A and B coefficients.
lasers [accept masers before "light"]