Relativistic optical rectification driven by a high-intensity pulsed Gaussian beam

Gin-yih Tsaur and Jyhpyng Wang

Accepted Wednesday Jun 24, 2009

Relativistic optical rectification is analyzed by utilizing the analytical solutions of the three-dimensional collective electron motion driven by a high-intensity pulsed Gaussian beam. Under the paraxial expansion the slowly varying components in the nonlinear oscillation of electron density and electric current are extracted from the solutions first, then they are used in the Maxwell equations as the source terms to calculate the terahertz electromagnetic fields as functions of the spatiotemporal amplitude of the pulsed Gaussian beam. The analysis compares well with available experimental data and computer simulations, and demonstrates the general scheme of paraxial expansion for the analysis of relativistic nonlinear optical interactions.