Application Description

Pump-probe schemes are used to measure ultrafast phenomena using short laser pulses. As the pump pulse impinges on the sample, various physical phenomena can be induced – for instance, an electronic excitation. After an adjustable time delay often controlled with an optical delay line, a probe pulse hits the sample: its transmission and/or reflection is consequently measured. By monitoring the probe signal as a function of the time delay, it is possible to obtain information on the decay dynamics of the generated excitation.

A key aspect of pump-probe measurements is that the time resolution is governed by the duration of the laser pulses and not the bandwidth of the photodetectors or the signal-recording electronics. Numerous techniques investigating ultrafast phenomena are based on the pump-probe scheme, such as THz and Raman spectroscopy.