Abstract-Stimulated Brillouin scattering of terahertz electromagnetic pulses in paraelectrics

V. Grimalsky, S. Koshevaya, J. Escobedo-Alatorre, E. Jatirian-Foltides,

https://link.springer.com/article/10.1007/s00340-018-7125-4


The nonlinear acoustoelectromagnetic phenomena in the terahertz (THz) range in the crystalline paraelectric SrTiO3 are investigated theoretically. The goal is to investigate an appearance of short THz electromagnetic (EM) pulses. The moderate cooling to the temperature T ≈ 77 K is considered. The resonant three-wave interaction of two counterpropagating EM THz waves with the longitudinal acoustic wave of the difference frequency is under investigation that is called the stimulated Brillouin scattering. This resonant interaction is due to the quadratic nonlinearity called electrostriction. The appearance of short EM pulses is possible when the input amplitudes of the signal EM wave are comparable with the pump amplitude and the duration of the input pulses is quite long. In the temporal scale associated with the EM wave propagation within a crystal, the cubic EM nonlinearity and the EM wave dispersion affect this three-wave resonant interaction. Under the development of the resonant nonlinear interaction, the modulation instability occurs that results in the complex and even chaotic wave modulation.