Terahertz three-dimensional plasma resonances in InGaAs diodes: A hydrodynamic study

We investigate 3D plasma resonances in InGaAs n⁺ - n - n⁺ diodes undergoing an optical beating excitation at room temperature. For this sake, we calculate the electric field response in the middle of the diode regions by using a hydrodynamic approach coupled to a one-dimensional Poisson solver. The results show clearly the presence of three-dimensional plasma resonances in the terahertz frequency domain for the two region types. We also emphasize a strong coupling between the plasma modes. Finally, the influence of both geometry and doping profile on the amplitude and the frequency of the resonances is evaluated.