ELFT HÍRADÓ

[Zoltan Tibai <tibai AT fizika.ttk.pte.hu>]

*PTE TTK Fizikai **Intézet** és a PAB meghívja*
*Nelson M. Mbithi*
(PTE)

Scaling up of terahertz energies based on semiconductor sources and
optimization of THz detection techniques

*c. előadására*


PTE TTK  E/417. előadó terem
2019. 06. 11. (Kedd) 14:00

Abstract:

Intense THz pulses in the low (0.1-2 THz) and mid (2-20 THz) frequency
parts of the THz spectrum enable the development of new compact particle
and x-ray sources for technological and scientific applications. Use of
contact grating (CG) technology has been proposed as an efficient method
for scaling up THz pulses to high energies, generated by optical
rectification of femtosecond laser pulses with tilted pulse front. This
method is applicable for semiconductor nonlinear materials. At a
sufficiently long pump wavelength two-and three-photon absorption can be
suppressed, together with the associated free-carrier absorption in the THz
range. Simulations of CG design parameters in the wavelength range of
1.7-2.2 µm are presented in case of GaP. Diffraction efficiencies as high
as 90% have been achieved with binary profiles. Furthermore, crystal
orientation for maximum THz generation and enhanced distortion-free
electro-optic sampling measurements have been carried out.