The pulse shape of a passively Q-switched microchip laser
Université Libre de Bruxelles, Optique Nonlinéaire Théorique,
Campus Plaine, C.P. 231, 1050 Bruxelles, Belgium
2 Air Force Research Laboratories, Nonlinear Optics Center of Technology, AFRL/DELO, 3550 Aberdeen Ave. SE, Kirtland AFB, NM 87117-5776, USA
Published online: 15 June 2000
The shape of the intensity pulse of a passively Q-switched microchip laser is investigated numerically and analytically. Our analysis is motivated by independent microchip laser experiments exhibiting nearly symmetric pulses in the case of a semiconductor saturable absorber and asymmetric pulses in the case of a solid state saturable absorber. Asymptotic methods are used to determine limiting behaviors of the pulse shape for both symmetric and asymmetric pulses. In the first case, we determine a sech2 solution parametrized by one parameter which can be determined by solving two coupled nonlinear algebraic equations. In the second case, the pulse solution is decomposed into two distinct approximations exhibiting different amplitude and time scales properties. We review earlier approximations of the repetition rate and the pulse width.
PACS: 42.65.Sf – Dynamics of nonlinear optical systems; optical instabilities, optical chaos and complexity, and optical spatio-temporal dynamics / 42.55.Sa – Microcavity and microdisk lasers / 42.60.Gd – Q-switching
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000