Abstract-Theoretical analysis of conditions for observation of plasma oscillations in semiconductors from pulsed terahertz emission

Antanas Reklaitis^1,a)

1 Semiconductor Physics Institute, Center for Physical Sciences and Technology, A. Goshtauto 11, Vilnius 01108, Lithuania
http://scitation.aip.org/content/aip/journal/jap/116/8/10.1063/1.4894163
a) Electronic address: reklaitis@pfi.lt.
J. Appl. Phys. 116, 083107 (2014); http://dx.doi.org/10.1063/1.4894163

Oscillations of electron-hole plasma generated by femtosecond optical pulse in freestandingsemiconductor are studied using hydrodynamic model and Monte Carlo simulations. The conditions required for the observation of coherent plasma oscillations in THz emission fromsemiconductor are determined. It is shown that several conditions have to be fulfilled in order to observe coherent plasma oscillations. First, the intensity of the optical pulse must exceed some threshold value. Second, the optical absorption depth must exceed the thickness of the built-in electric field region. Third, the generation of electron-hole pairs with uniform illumination is required, i.e., the laser beam with the flattop intensity profile has to be used. It is found that the duration of the optical pulse does not play a vital role in the development of plasma oscillations.