Chaos in aCO2waveguide laser due to transverse-mode competition

Abstract
We report on the spontaneous onset of temporal chaos in a waveguide CO2 laser due to the interaction between two transverse modes. A nonstandard configuration of the resonator has been used in order to obtain multitransverse mode operation. Starting from a mirror setting where two modes have a stable coexistence, further tiny variations of the cavity length induce a period-doubling cascade to chaos.