Experimental observation of double-peak structure of coincidence spectra in ultrafast spontaneous parametric down-conversion
Dmitry A. Kalashnikov, Mikhail Vladimirovich Fedorov, Leonid A. Krivitsky · Physical Review A · 2013
The requirement for symmetry of the biphoton wave function results in a double-peak structure of the coincidence spectra of spontaneous parametric down-conversion (SPDC) [Fedorov, Mikhailova, and Volkov, Phys. Scr. 85, 058105 (2012)]. In this work we report the experimental observation of this effect by carefully tailoring parameters of the SPDC crystal, the ultrafast pump laser, and the measurement setup. The results are shown to be relevant to quantum state engineering of ultrafast polarization or frequency-entangled mixed states.