Single-frequency Emission Research Articles

Stable single-frequency emission of an argon-ion laser under line competition conditions

An investigation was made of the possibility of single-frequency emission of an argon-ion laser in the case of the simultaneous activity of two coupled transitions 4p2D05/2 → 4s2P3/2 and 4p4D05/2 → 4s2P3/2. The coherent emission spectra of both transitions were investigated. The regions of normal and anomalous competition between these transitions were determined. The criteria for single-frequency emission were established. An oscillographic study was made of the dependence of the emission spectrum on the discharge parameters.

Investigation of the competition between two axial modes in a laser with a homogeneously broadened line

An experimental investigation was made of the competition between two axial modes emitted by a helium–neon laser with a homogeneously broadened λ = 3.39 μ line. The 3s2–3p4 line of Ne was used as a model of a homogeneously broadened transition. The region of stable two-frequency emission was investigated as a function of the laser parameters. A study was also made of the transition for the two- to the single-frequency emission, which occurred when the competing modes converged. A qualitative explanation of the observed effects was provided on the basis of a simple physical model, in which use was made of the formation of a dip in a homogeneously broadened line under the influence of the saturation field. The results obtained should apply qualitatively to other lasers with homogeneous line provided T2 T1 (T1 and T2 are, respectively, the longitudinal and the transverse relaxation times) and provided the spatial distribution of the inversion is not affected by the standing light waves of the competing modes.