A direct pump and probe lifetime determination in the ps regime has been made in quantum wells of Si/Si1-xGex. We have used an rf linac-pumped free-electron laser to determine the relaxation time associated with intersubband absorption in Si/SiGe quantum wells with a subband separation smaller than the optical phonon energy. This measurement yields a lifetime of T1=30 ps.© 1995 American Institute of Physics.
|Journal||Applied Physics Letters|
|Publication status||Published - 1995|