Room temperature dual-mode internal quantum deficiency measurement with propagated uncertainty to 0.03% (k = 2)

We present improvements in dual-mode calibration of predictable quantum efficient detectors
and demonstrate the importance of calculating absolute uncertainties instead of relative
uncertainties. We have implemented a new uncertainty component for the thermal fluctuations in
the temperature signal which results in a propagated Type A uncertainty, matching the observed
standard deviation. A new thermal drift correction method exploiting a monitor thermistor on
the heat sink is relaxing the need for thermal stabilisation of the experimental set-up. With beam
position uncertainty ±0.25 mm and background electrical power varying from 10 μW to
900 μW, the measured internal quantum deficiency (IQD) is in average 0.00% ± 0.03% (k = 2).
The IQD exhibits clear systematic effects of beam position and background power, showing the
need for improved design of dual-mode modules to further improve the uncertainty.