Quantum path analysis of isolated attosecond pulse generation by polarization gating

The generation of isolated attosecond pulses using the polarization gating technique is analyzed considering the single-atom response to an intense pulse with a time-dependent ellipticity. The influence of the carrier-envelope phase of the driving pulses on the characteristics of the harmonic spectra is discussed in combination with the concept of quantum trajectory followed by the electrons. We show that the control of the polarization state of the pulse opens important possibilities for synthesizing particular attosecond pulse wave form.