Quantitative rescattering theory for high-order harmonic generation from aligned molecules

By employing the recently proposed Quantitative Rescattering Theory (QRS) combined with accurate photoionization transition dipoles for aligned molecules, we show that most of the existing experimental results for high-order harmonic generation (HHG) from CO$_{2, }$N$_{2}$, and O$_{2}$ can be nicely reproduced. In our calculations, the returning electron wavepackets are obtained from the strong-field approximation or from solution of the time-dependent Schrodinger equation for a reference atom, whereas the transition dipoles are obtained from state-of-the-art molecular photoionization calculations. Our results show that quantitative description of the HHG from aligned molecules has become possible.