We report on the production of atomic hydrogen subsequent to the 193 nm photolysis of triethylarsenic (TEAs) using an excimer laser. The H atoms are probed via two‐photon (121.6+364.7 nm) ionization, and the resulting H atom Doppler profile at Lyman‐&agr; is presented. Photolysis power dependence studies demonstrate that substantial H atom formation occurs at relatively low laser powers. However, the H atom signal actually begins to diminish as the photolysis laser power is increased beyond ∼70 MW/cm2. Correlations with time‐of‐fight mass spectral data suggest that ion channels are being accessed. The possible mechanisms for TEAs excitation that lead to H atom formation/depletion are presented, and the implications of these observations on controlling carbon incorporation in the laser‐enhanced growth of films of GaAs, AlGaAs, etc. are discussed.