Space-time metrology and control of high-power femtosecond lasers

One of the major achievements of optics in recent decades has been the generation of light pulses of extremely short duration, down to a few femtoseconds in the 1990's and tens of attoseconds in the past few years. Throughout the development of these sources, the ability to accurately measure the temporal properties of ultrashort light pulses has been crucial. Several well-established techniques are now available to measure their electric field E(t) from the femtosecond down to the attosecond range. However, within any ultrashort beam, the temporal properties of the light pulse can vary spatially and vice versa. Such correlations between the spatial and temporal properties are called spatiotemporal couplings (STCs) and prevent the decomposition of the laser field E(t, r) as E(t, r) = f(t) g(r).