Abstract

Simultaneous oscillation in the ⁴F_3/2→⁴I_13/2 and ⁴F_3/2→⁴I_11/2 laser channels of Nd³⁺ has potential application in high brightness displays and in generation of multiple wavelengths in the same laser system by nonlinear frequency conversion exploiting both wavelengths. For instance, a laser system capable of generating red, green and blue laser radiation simultaneously can be realized¹. Sum-frequency mixing of both wavelengths produces visible radiation around 600 nm, where diode-pumped solid-state lasers are not frequent specially in continuous-wave. Up to date, the number of systems in which this possibility has been demonstrated is reduced. The rather complex competition dynamics of simultaneous oscillation in the same crystal is governed by the relative gain cross section at each channel in a “winner takes all” dynamics². We present a study of how spatial hole burning (longitudinal and transversal) in a standing wave cavity can be exploited to help achieving continuous-wave simultaneous oscillation in laser media of different spectral broadening character. The results suggest that the number of Nd³⁺ based laser crystals or glasses in which simultaneous oscillation can occur may be significant. Figure 1 shows how the relative power threshold in both channels scales essentially as the square of the relative gain cross section in the presence of longitudinal hole burning.

© 2001 EPS