Pump-wavelength dependence of terahertz radiation via optical rectification in (110)-oriented ZnTe crystal

Department of Physics, Shanghai University, 99 Shangda Road, Shanghai 200444, People’s Republic of China
Journal of Applied Physics (Impact Factor: 2.19). 07/2008; 103(12):123101 - 123101-4. DOI: 10.1063/1.2938847
Source: IEEE Xplore

ABSTRACT The optical pump-wavelength-dependent generation and detection of terahertz wave in (110)-oriented ZnTe crystal were demonstrated. By using femtosecond laser pulses, terahertz radiation was generated. Both simulations and experimental results show that the terahertz wave in the frequency range of about 4–1 THz can be obtained by tuning the pumping wavelength from 700 to 900 nm. The theoretical analysis shows that the matching between the optical group velocity and terahertz phase velocity plays an important role for terahertz frequency tuning. The present studies also demonstrate that both the terahertz generation and detection are applicable in a single nonlinear optical crystal.

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