Quantum technology is considered to be a key technology of the future. It enables the development of highly efficient technology that can far surpass the performance of conventional systems. By controlling individual quanta, i.e. the smallest light and energy components, disruptive applications are made possible, for example in the field of data processing (quantum computers), communications (tap-proof communications) and metrology (quantum imaging, quantum sensor technology).

IMMS is researching the use of single photon detectors (SPAD), which are manufactured in a standard semiconductor technology (CMOS). They are used to convert single photons into electrical signals and allow operation at room temperature without large and complex cooling systems. Statistical evaluation is required to interpret the sensor signals, which is performed by a programmable logic device (FPGA). In addition, the integration of such an optical sensor element in conjunction with the necessary evaluation electronics in a microchip is also being targeted.

IMMS has developed a SPAD evaluation kit in collaboration with X-FAB. The low-cost, hand-sized USB device called SPAD-EvalKit requires no additional power, is based on the time-correlated single-photon counting (TCSPC) method and enables measurements with a temporal resolution of 20 picoseconds. The TCSPC method used for this purpose makes it possible to assess the temporal course of the intensity of light pulses. It can be used to set up single-photon sources, characterise light pulses with very small light powers or distances and thus lay the foundations for quantum-based applications. Among other things, the method can be used to develop new solutions for in-vitro diagnostics or medical technology, such as miniaturised luminescence and fluorescence measurement technology.

To interpret the sensor signals statistical evaluation is required. For the first SPAD evaluation kit, this is taken over by a programmable logic device (FPGA). This component is an intermediate step for later chip development. The FPGA can be used to specify the processes for sensor signal processing, but primarily to map the desired circuit structure, which can still be flexibly adapted for tests and optimisations.

This laid the foundation for the integration of such an optical sensor element in conjunction with the necessary evaluation electronics in a microelectronics chip, which will flow into application developments of other research projects.