LONG-TERM SPECTRAL RESPONSIVITY STABILITY OF PREDICTABLE QUANTUM DETECTORS

摘要

In recent years a Predictable Quantum Efficient Detector (PQED) has been developed by a joint European effort in the framework of the EUROMET iMERA+/EMRP programs. The PQED consists of two custom-made induced junction Silicon photodiodes in a wedge trap configuration. The most notable property of this type of detector is that its external quantum efficiency (EQE) value in the spectral range from 400nm to 850nm is dependent only on fundamental constants. The PQED is therefore potentially an ideal candidate for a new primary standard for optical radiometry in the visible range. A considerable effort has been spent to validate the absolute value of the PQED spectral responsivity against the current standard for optical radiometry, the cryogenic radiometer, with standard uncertainty below 100 ppm. The aim of this work is to investigate the PQED long term temporal stability when operated at room temperature.