THz Emission Spectroscopy

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In terahertz emission spectroscopy (TES), the sample itself is the source of THz emission.  The THz waveform is analyzed to garner information about the process responsible for the emission (optical rectification, shift currents, charge transfer, etc.) and other processes which may compete with and thus hinder THz generation. 

As seen in the figure below, the TES setup incorporates our regeneratively amplified Ti:Sapphire laser.  The 800-nm optical beam is split into two parts: THz generation (>99%) and THz detection.  The majority of the light is used to generate THz radiation in the sample.  The half waveplate and polarizer are used to control the polarization of the generation beam.  The setup contains no focusing or collimating optics so that the THz waveform is not distorted in any way between generation and detection.  The smaller portion of the optical beam is used to detect the emitted THz radiation in a ZnTe(110) crystal using free space electro-optic sampling (FSEOS).   

TES

Figure 1. The TES setup.

Related Publications

Schleicher, J. M., S. M. Harrel, and C. A. Schmuttenmaer , Effect of spin-polarized electrons on terahertz emission from photoexcited GaAs , J. Appl. Phys. , 2009 , 105

 

Beard, M. C., G. M. Turner, and C. A. Schmuttenmaer , Measuring intramolecular charge transfer via coherent generation of THz radiation , J. Phys. Chem. A , 2002 , 106 , 878-883