Measurement of the phase of few-cycle laser pulses

Abstract

Attosecond science can take enormous advantage of intense laser pulses consisting of two optical cycles or less (few-cycle pulses). The temporal variation of the field, which directly governs strong-field interactions, therefore depends on whether the maximum of the pulse amplitude coincides with that of the wave cycle or not, i.e. on the phase of the field with respect to the pulse envelope. It is demonstrated that the direction of electron emission from photoionized atoms can be controlled by varying the phase of the field, providing a tool for its accurate determination. Different phase-dependent effects in strong-field photoionization and their suitability for phase measurement are discussed as well as the limitations of the f -to-2 f scheme.