New Journal of Physics

doi:10.1088/1367-2630/10/2/025033 Abstract. The dynamics and propagation effects in attosecond (asec) pulse generation from high-order harmonic generation (HHG) of aligned one-dimensional (1D) H+2 molecules are investigated from numerical solutions of fully coupled Maxwell and time-dependent Schrödinger equations (Maxwell-TDSEs), in the highly nonlinear nonperturbative regime of laser–molecule interaction. Density, laser-phase and propagation length effects are studied on the total electric field and nonlinear polarization from the Maxwell-TDSE for intense few cycle (800 nm) laser pulses interacting with a 1D H+2 gas. We show how single and double asec pulses can be generated and propagated as a function of the phase of individual harmonics created by ultrashort intense laser pulses in aligned H+2 molecules. We find furthermore extension of maximum HHG plateaux with increasing gas pressure