Monolithically integrated Fabry-Perot saturable absorber

Abstract

Saturation intensity and loss of a saturable absorber are substantially independently regulated by positioning the saturable absorber element within a Fabry-Perot etalon defined by first and second reflective elements so that the saturable absorber element responds to light at optical wavelengths in the anti-resonant portion of the Fabry-Perot spectral response, that is, between optical wavelengths corresponding to resonance peaks. The resulting combination of elements is called a Fabry-Perot saturable absorber. Thickness of the saturable absorber element substantially sets the loss of the Fabry-Perot saturable absorber while changes in the reflectivity of the first reflective element onto which the light is incident substantially determines the saturation intensity (degree of nonlinearity) and assists in compensating loss of the saturable absorber element. In one exemplary embodiment, a high reflectivity first reflective element is positioned on the end of the saturable absorber element facing the incident optical radiation while a high reflectivity second reflective element is positioned on the opposite end of the saturable absorber. Dielectric material layers form the first reflective element whereas semiconductor layers form the second reflective element. A plurality of quantum well and barrier layers are employed to form the saturable absorber element.

Dependencies are inferred from the claim text.