Mode Competition Effects Research Articles

Coexistence and noncoexistence of modes in a multi-mode laser

Mode competition effects in a cw multi-mode laser with a broad homogeneous emission line are studied theoretically, taking account of a Lorentzian gain profile. Explicit formulas are presented for the frequency range in which simultaneous oscillation of modes takes place, and the tuning range for a selected mode (the latter being privileged by a lower loss). Moreover, a novel spectroscopic technique introduced and successfully applied recently, is analysed. The experimental procedure consists in first restricting the oscillation range by means of filter and afterwards observing the additional spectral broadening of the laser output, which is caused by placing a narrow-band absorber inside the laser cavity. A useful formula allowing to estimate the sensitivity of this technique is derived.

An Nd:YAG laser whose active medium experiences no hole burning effects

An arrangement is described in which the effect of the standing waves on the active medium is eliminated by placing it between 1 4 -wave retardation elements. As a result the active medium experiences no hole burning or mode competition effects. The emission characterestics of this laser were found to be different from those of a standard laser system. The laser could be operated at repetition rates of up to 40 pps and its output consisted of completely regular pulses whose period and amplitude could be controlled by the pumping process.

Use of the mode competition effect in a helium-neon laser for measurements of small acoustic vibration amplitudes

Use of the mode competition effect in a helium-neon laser for measurements of small acoustic vibration amplitudes

Mode Competition and Collision Effects in Gaseous Optical Masers

Mode Competition and Collision Effects in Gaseous Optical Masers