Ultrafast response of a plasma Bragg mirror

Summary form only given. Multilayer mirror structures for the near-infrared (NIR) have found a wide application in laser technology. The development of vertical-cavity surface-emitting lasers (VCSELs) has been possible due to the advances in the growth of semiconductor Bragg mirrors. The extension of VCSEL technology to the mid-infrared (MIR) regime has only been accomplished recently. We present a Bragg mirror that consists of only one type of semiconductor material and works at the longest wavelength (11.5 /spl mu/m) reported so far. The difference in the refractive index of the layers is realized by different doping levels rather than different dielectric materials. The use of doped materials for the layers offers the possibility to not only use them for light confinement but also as contacting layers to supply the current to the active zone of a semiconductor laser. We apply cross-correlation spectroscopy to study in amplitude and phase the time-resolved reflectivity properties of this new plasma Bragg mirror.