Rethinking Spectroscopy with Astrophotonics – by Suresh Sivanandam

Abstract: Astrophotonics is an emerging field that can potentially supplant conventional astronomical instruments. I will provide a quick overview of the present state-of-the-art in astrophotonic instrumentation along with their associated pros and cons. 

I will discuss a new approach to traditional spectroscopy using photonic devices. Given that most spectroscopic problems in astronomy require some form of cross-correlation, e.g., measurement of kinematics or detection of atomic/molecular species, we have developed a new approach where the cross-correlation can be done entirely on-device. By creating photonic devices with a carefully designed transmission spectrum that can be modulated, the cross-correlation can be carried out optically, which vastly simplifies the instrument. These devices can be purpose-built to solve specific scientific problems. They are several orders of magnitude cheaper than echelle spectrographs, and can potentially be tiled on a focal plane to form an IFU. Lastly, I will present initial test results from devices we have recently fabricated.

Please email info@astro.utoronto.ca for permissions to access this colloquium recording.