Dr. Mikael Malmström, Laser Physics, KTH

Abstract

In this seminar I will present the results of my PhD thesis concerning all-fiber modulators for laser applications. The modulators used were based on exploiting either the elasto-optic effect or the electro-optic effect to achieve refractive index change in the core of the fiber-components. This was realized with the aid of electrodes inside the fiber cladding close to the core that provided either thermal stress in the core, or an electric field across the core. The electrodes consisted of low melting-point alloys, such as BiSn and AuSn, which were pushed into the hole-fiber, in the liquid state, which then solidified to form solid electrodes filling the entire hole. Together with an analyzer such as a polarizer or an interferometer the achieved refractive index modulation in the core could then be translated into an amplitude modulation of the guided light, which was subsequently utilized for switching fiber-lasers to generate cavity dumped, Q-switched, or mode-locked pulses.