A pump-probe LFP system is adapted to a substantially lower energy requirement of a pump light source and a probe light source. The LFP system includes a photonic crystal fiber based probe light source, a pump light source adapted to produce light pulses with nanojoule or higher energy, a main laser source to generate a first beam portion to the probe light source and a second beam portion to the pump light source, a delay generator, computer, an optical modulator, and a detector.