Monte Carlo simulation of near-field terahertz emission from semiconductors

We simulated the carrier dynamics in InGaAs after ultrafast photoexcitation. By using a finite-difference time-domain approach we were able to analyze the near terahertz field emission caused by the motion of such carriers. We found that both the current parallel and normal to the interface take a relevant role in the terahertz emission. We also found that the ballistic motion of the carriers after photoexcitation dominates the emission rather than diffusion.