Ultrashort Laser Pulse Phenomena, 2nd Edition

378 Ultrashort Sources II: Examples

Semi-Integrated Circuit Fs Lasers

Total integration as shown above results in a high duty cycle, at the expense of

a lower energy per pulse. On can seek a compromise between the discrete

elements semiconductor laser and the total integrated laser. For instance, the

integration of the gain and saturable absorber of the integrated laser of Chen and

Wang [138] can be maintained in a single element coupled to an external cavity.

Such a design has been successfully tested by Lin and Tang [139]. The absorber

consists of a 10 µm island in middle of the gain region, with an electrical contact,

isolated from the gain structure by two 10-µm shallow etched regions (without

any electrical contact). The absorption—as in the