Designing high-power, octave spanning entangled photon sources for quantum spectroscopy

Entangled photon spectroscopy is a nascent field that has important implications for measurement and imaging across chemical, biology, materials fields. potentially offers improved spatial temporal-frequency resolutions, increased cross sections multiphoton nonlinear measurements, new abilities in inducing or measuring quantum correlations. A critical step enabling entangled spectroscopies the creation of high-flux sources can use conventional detectors, as well provide redundancy losses realistic samples. Here, we report periodically poled, chirped, lithium tantalate platform generates pairs with $10^{-7}$ efficiency. For near watt level diode laser, this results $\mu$W-level flux. The single per mode limit necessary to maintain non-classical behavior still satisfied by distributing power over up an octave-spanning bandwidth. spectral-temporal correlations are observed via Michelson-type interferometer measures broadband Hong-Ou-Mandel two-photon interference. coherence time 245 fs 10 nm bandwidth collinear case 62 125 non-collinear measured using CW pump and, essentially, collecting full cone. We outline detail numerical methods used designing tailoring photons source, such changing center wavelength bandwidth, ultimate aim increasing availability UV-Vis optical community.