Broadband biphoton source for quantum optical coherence tomography based on a Michelson interferometer

Broadband correlated photon pairs (biphotons) are valuable in quantum metrology, but current generation methods either involve complex nonlinear structures or lack sufficient bandwidth and brightness. In this work, we theoretically describe and experimentally demonstrate a novel technique for generation of a bright collinear biphoton field with a broad spectrum, achieved by using a tightly focused pump in a bulk nonlinear crystal. As the most straightforward application of the source, we employ Michelson interferometer-based quantum optical coherence tomography (QOCT). Utilizing the source enables the demonstration of record resolution and dispersion cancellation for this QOCT scheme.Comment: 7 pages, 4 figure

Investigation of 4,6-di(hetero)aryl-substituted pyrimidines as emitters for non-doped OLED and laser dyes

Two novel V-shaped push-pull systems based on a pyrimidine acceptor have been designed and investigated. Low-temperature measurements of the fluorescence and delayed luminescence spectra demonstrated that the emission bands of the compounds have a charge-transfer character. Despite the fact that compounds in thermal vacuum deposition films have a low fluorescence quantum yield, OLED devices based on them show high efficiency, which can be associated with the emission mechanism through delayed fluorescence. It is found that photoproducts, obtaining upon exposure to UV-irradiation of fluorophores in chloroform solution, exhibit laser activity in the red region of the spectrum