Picosecond Optical Measurements of Band-to-Band Auger Recombination of High-Density Plasmas in Germanium

Abstract

The recombination kinetics of transient high-density electron-hole plasmas in germanium has been measured by time-resolved free-carrier absorption with picosecond optical pulses. Density-dependent recombination rates as high as 4 × ${10}^9$ ${\sec }^{-1\mathrm{}}$ have been observed in plasmas with initial densities up to 3.4 × ${10}^{20}$ ${\mathrm{cm}}^{-3\mathrm{}}$. At this density the band-to-band Auger rate constant, ${\gamma }_3=n^{-3\mathrm{}}\frac{\partial n}{\partial t}$, is found to be 1.1 × ${10}^{-31\mathrm{}}$ ${\mathrm{cm}}^6$ ${\sec }^{-1\mathrm{}}$ at room temperature in germanium.