A mode-locked solid state laser is disclosed for generating ultrashort optical pulses from a semiconductor type laser. A semiconductor pulse slicer/demultiplexer/modulator with gain amplification is used to modulate and amplify a generated optical beam whether or not the beam is pulsed, continuous wave, q-switched, or modelocked. Alternatively, the semiconductor pulse slicer/demultiplexer/modulator with gain amplification is used to gate a generated optical beam whether or not the beam is pulsed, continuous wave, q-switched, or modelocked. Alternatively, the semiconductor pulse slicer/demultiplexer/modulator with gain amplification is used to demultiplex a generated optical beam whether or not the beam is pulsed, continuous wave, q-switched, or modelocked. The invention uses only semiconductor type materials such as Titanium Saphire, Gallium Arsenide, Aluminum Gallium Arsenide (GaAs/AlGaAs) as both the pulse slicer/demultiplexer/modulator with gain amplification, and the mode-locked l