TWOCOLOR MIDINFRARED SPECTROSCOPY

1
Van der WaalsZeeman
Institute, University of Amsterdam
TWO-COLOR MID-INFRARED SPECTROSCOPY OF OPTICALLY
DOPED MEDIA
M. Forcales, M.A.J. Klik, N.Q. Vinh, M. Wojdak,
and T. Gregorkiewicz Van der Waals-Zeeman
Institute, University of Amsterdam,
Valckenierstraat 65, NL-1018XE Amsterdam, The
Netherlands
Application of mid-infrared radiation from a
free-electron laser opens new possibilities for
optical spectroscopy of solids. In combination
with above-bandgap excitation, this technique is
especially suited for investigations of energy
transfers within optically doped semiconductors.
It can also be conveniently applied for tracking
excitation mechanisms of optically doped large
bandgap media. In the poster this novel
experimental approach is introduced and some
recent results are shown. These include optical
memory effect in SiEr and ZnSeCr,
free-carrier-induced Auger recombination in
SiAg, SiCu and SiEr (Tann1000C), optical
backtransfer effect for InPYb, optical
generation of phonons in ZnSe and SiEr,O,
carrier tunneling in intense electric field of
MIR laser for InPYb, and details of energy
transfers in SiO2nano-Si, SiO2nano-Si,Er.
Optical memory effect

• Possible effects in MIR
• Ionization of
• (shallow) impurities
• (local) Phonon
• generation
• Excited state
• absorption

• Precise energy
• FEL 70-170 meV
• OPO 0.56-2.9eV
• T of choice
• Delay time ?t
• Power
• Time resolution

Auger quenching
Phonon generation
Optical backtransfer InPYb
ZnSeCr - ASL (DAP)
ASL
SiEr,O
Energy transfers in SiO2nc-Si, SiO2nc-Si,Er
Carrier tunneling (InPYb)
CONCLUSIONS

• Powerful tool for (dynamical)
• investigation of energy transfers
• Spectroscopy of thermal effects