A method of carrier-envelope phase control for few-cycle laser pulses

摘要

The shape of the field of a few-cycle laser pulse strongly depends on the carrier-envelope phase. For a circularly polarized few-cycle pulse, this phase is correlated with a direction in space. Superposition of two counterrotating circularly polarized few-cycle pulses yields a linearly polarized pulse. Highenergy electrons.. generated through above-threshold ionization by such a combination of pulses, are emitted in a direction correlated with the carrier-envelope phase. Based on these facts, we propose two schemes for direct measurement and control of the carrier-envelope, phase and the phase slip of a pulse train.