Photon arrival time tagging with many channels, sub-nanosecond deadtime, very high throughput, and fiber optic remote synchronization

Abstract

Time-Correlated Single Photon Counting (TCSPC) and time tagging of individual photon detections are powerful tools in many quantum optical experiments and other areas of applied physics. Using TCSPC, e.g., for the purpose of fluorescence lifetime measurements, is often limited in speed due to dead-time losses and pile-up. We show that this limitation can be lifted by reducing the dead-time of the timing electronics to the absolute minimum imposed by the speed of the detector signals while maintaining high temporal resolution. A complementing approach to speedy data acquisition is parallelization by means of simultaneous readout of many detector channels. This puts high demands on the data throughput of the TCSPC system, especially in time tagging of individual photon arrivals. Here, we present a new design approach, supporting up to 16 input channels, an extremely short dead-time of 650 ps, very high time tagging throughput, and a timing resolution of 80 ps. In order to facilitate remote synchronization of multiple such instruments with highest precision, the new TCSPC electronics provide an interface for White Rabbit fiber optic 1 Author to whom correspondence should be addressed; electronic mail: wahl@picoquant.com 1 networks. Beside fundamental research in the field of astronomy, such remote synchronization tasks arise routinely in quantum communication networks with node to node distances on the order of tens of kilometers. In addition to showing design features and benchmark results of new TCSPC electronics, we present application results from spectrally resolved and high-speed fluorescence lifetime imaging in medical research. We furthermore show how pulse-pile-up occurring in the detector signals at high photon flux can be corrected for and how this data acquisition scheme performs in terms of accuracy and efficiency.

The biochemical resolving power of fluorescence lifetime imaging: untangling the roles of the instrument response function and photon-statistics

“…the inability of resolving a second photon while the detection system is still busy handling the electrical trace of the first (due to the combined effect of the detector and the electronics deadtimes), or difficulties in detecting multiple photons per light pulse. We have made significant progress in ameliorating pulse pile-up effects, for example, by utilizing multi-hit time-to-digital [7,8] or multiplexed time-to-analog converters [9], ultra-fast digitizers [10], fast detectors (e.g. hybrid photomultipliers [11]), and detector arrays [12][13][14][15].…”

“…Here, we provide the Fisher information analysis and Monte Carlo simulations to fill this gap in knowledge. Given that the recent developments of fast and efficient FLIM systems within the biomedical community have been stimulated by methodological advances, such as hybrid photomultiplier tubes [11], multi-hit time-to-digital converters [7,8], integrated smart-pixel technologies [27,28], and ultra-fast digitizers [10], we specifically focused on how limitations in the instrument temporal resolution impacts the 'biochemical resolving power' [24]. We envisage that a deeper understanding of the trade-offs required for the development of FLIM systems designed for biomedical applications will aid the community to break new ground in the development and application of biochemical imaging.…”

Biochemical resolving power of fluorescence lifetime imaging: untangling the roles of the instrument response function and photon-statistics

“…the inability of resolving a second photon while the detection system is still busy handling the electrical trace of the first (due to the combined effect of the detector and the electronics dead-times), or difficulties in detecting multiple photons per light pulse. We have made significant progress in ameliorating pulse pile-up effects, for example, by utilizing multi-hit time-to-digital [ 7 , 8 ] or multiplexed time-to-analog converters [ 9 ], ultra-fast digitizers [ 10 ], fast detectors ( e.g. hybrid photomultipliers [ 11 ]), and detector arrays [ 12 – 15 ].…”

“…Here, we provide the Fisher information analysis and Monte Carlo simulations to fill this gap in knowledge. Given that the recent developments of fast and efficient FLIM systems within the biomedical community have been stimulated by methodological advances, such as hybrid photomultiplier tubes [ 11 ], multi-hit time-to-digital converters [ 7 , 8 ], integrated smart-pixel technologies [ 29 , 30 ], and ultra-fast digitizers [ 10 ], we specifically focused on how limitations in the instrument temporal resolution impacts the ‘biochemical resolving power’ [ 26 ]. We envisage that a deeper understanding of the trade-offs required for the development of FLIM systems designed for biomedical applications will aid the community to break new ground in the development and application of biochemical imaging.…”

Modifying quantum optical states by zero-photon subtraction

“…After a 20-second exposure, the mean counting rate at D 2 is calculated with and without this postselection. Then the D 2 dark count rate (∼80 Hz, after filtering [28]) is subtracted from each of these values, and their ratio is taken to obtain K. This is repeated for multiple values of VBS reflectance R, revealing the behavior of K(R) for each state.…”