Extended propagation of sub-mm incoherent space-time fields over 110 m distance

Space-time (ST) wave packets are propagation-invariant pulsed beam endowed with a tight correlation between the underlying spatial and temporal frequencies. We present a theoretical formulation and experimental demonstration of sub-millimeter incoherent ST light sheets traversing 110 m without significant diffraction. We synthesize ST fields of beam width ~ 0.7 mm from a superluminescent diode with a bandwidth of ~20 nm centered at 840 nm and observe propagation-invariant behavior across a distance of over 100-m distance in free-space. Finally, we study the effect of the aperture on the propagation distance and far-field beam size of ST light sheets.