Ultra-broadband spontaneous parametric down-conversion generation using supercontinuum laser in quantum-optical coherence tomography

Traditional spontaneous parametric down-conversion (SPDC) generally has a broad spectral band, while quantum optical coherence tomography (QOCT) aims to achieve an ultra-broadband joint spectrum to ensure good axial resolution. Ultra-broadband supercontinuum (SC) sources enable axial resolutions of approximately 1 µm in OCT. This study investigates the impact of ultra-broadband SPDC using an SC source to generate entangled photon pairs within the 700-1000 nm range. By examining the tuning capabilities and dimensional design of the Beta Barium Borate (BBO) crystal, we explore the combination of the OCT SC source and SPDC for QOCT. The findings contribute to future developments in QOCT.