Next-generation APD detector arrays for interferometric imaging

Creating images of the physical world is a universal task that spans physics, astronomy, life sciences, and numerous other disciplines. Detectors are the key technology to register light and to translate it into an electronic signal. However, the read-out process in detectors also introduces noise, in particular when observing at infrared wavelengths and when using very high frame rates. Avalanche photodiodes are a disruptive new detector technology that overcome the read-noise problem by amplifying the signal before it is being read out. Unfortunately, 1st-generation APD devices suffered from severe limitations, in particular a high background level that prevents long integration times and a small pixel format of these devices. We will procure two devices, where the first one will allow us to improve the sensitivity of our MIRC-X 6-telescope imager. The second device will enable technology developments using the latest generation of large-format APDs, where the goal is to characterise & optimise the read noise and dark current performance of the camera in the lab and then to deploy it in our upcoming BIFROST visitor instrument at the VLTI. This will benefit the research pursued by our STFC project as well as the research pursued by a broad community of users. We will engage with stakeholders in other disciplines to explore whether the large-format devices are suitable for applications outside of astronomy, for instance in biophysics and medicine.