Method for single-shot time- and fluence-resolved optical measurements at femtosecond excited surfaces

Summary form only given. The conventional technique allows time-resolved optical measurements in the pico- and femtosecond time domain. A strong pump excites the sample, and a time-delayed probe measures the pump-induced changes of optical properties. Varying the time delay between pump and probe the dynamics of the processes which follow short pulse excitation can be measured. However, this pump-probe scheme has several shortcomings: (i) Spatial averaging over the probed area may lead to misinterpretation of experimental data. (ii) For any delay time and any fluence the measurement must be repeated. (iii) At a given delay time and fluence averaging over several pulses is necessary due to statistical pulse-to-pulse variations of the laser properties. A complete experiment can be quite time-consuming, and sometimes, if nonreversible dynamics in small samples should be investigated, the method cannot be applied at all. The contribution describes a technique, which allows time- and fluence-resolved optical measurements at femtosecond excited surfaces in one laser shot.