Dispersive effects in the reflection of femtosecond optical pulses from broadband dielectric mirrors

The dispersive effects of high-reflectivity broadband mirrors on femtosecond optical pulses have been analyzed for three different multilayer structures. In each case the high-reflectivity zone can be divided into two different regions symmetrically located around the mirror central frequency: high-dispersion and low-dispersion regions. The calculated temporal behavior of the reflected pulse shows high distortion of the pulse profile, a frequency chirp, and a broadening as high as a factor of 5.6, due to a single reflection, within the high-dispersion region. The use of these types of mirror should therefore be strictly limited to their low-dispersion side.