Transient absorption and phase microscopy with balanced detection (Invited Paper)

This presentation focuses on the use of common path, birefringent, time-delayed interferometry to detect ultrafast pump-probe effects via phase, rather than absorption of the probe pulse, in a laser-scanning microscope. The method uses balanced detection to cancel relative intensity noise inherent to fiber laser sources. We compare absorption and phase measurements in graphene, hemoglobin, and red blood cells, and present a preliminary model for determining whether, for a given wavelength, absorption or phase will yield a stronger signal.