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Yi, Xiyu

Publications and source records attributed to Yi, Xiyu.

4 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Fluorescence lifetime measurements using photon pair correlations generated via spontaneous parametric down conversion (SPDC)

We have used photon pair correlations generated via spontaneous parametric downconversion (SPDC) to measure the fluorescence lifetime of the organic dye rhodamine 6 G, demonstrating that fluorescence lifetime measurements can be achieved using a continuous wave (CW) laser, without pulsed or modulated lasers. Our entangled photon method, quantum fluorescence lifetime (Q-FL) measurements, uses one photon to excite fluorescence and the resulting fluorescence photon is timed and referenced to the arrival time of the other entangled photon. Thus, we can exploit the short timescale of photon pair correlations to conduct experiments that are typically carried out with pulsed lasers and we show that the inherent timing of the photons is fast enough to resolve the nanosecond scale fluorescence lifetime of the sample. This measurement paves the way towards using the time correlations of entangled photons for fluorescence imaging; capitalizing on the presence of fast, sub-100 ps correlations that have not been demonstrated classically.

Eshun, Audrey (ORCID:0000000167697082)↗
DOE OSTI2023

Widefield three-dimensional microscopy with a quantum entanglement light source

Devices, systems and methods for widefield three-dimensional (3D) microscopy with a quantum entanglement light source are described. An example method includes generating a first set of photons and a second set of photons, wherein each of the photons in the first set is quantum entangled with a corresponding photon in the second set, directing the second set of photons toward a sample and simultaneously directing the first set of photons toward a first two-dimensional (2D) detector, detecting, from the sample, a plurality of photons at a second 2D detector, analyzing detections from the first and second 2D detectors to determine coincidence information, and determining one or more characteristics associated with at least a three-dimensional (3D) section of the sample based on collective detections at the first and the second 2D detectors.

Bond, Tiziana C.↗