Multi-photon states can play an important role for optical quantum information, but producing these effectively can be challenging. Most commonly, independent photon pairs are produced by downconversion and then combined probabilistically, using post-selection to obtain the desired multi-photon state. This dependence on post-selection limits the suitability of the resulting states for some application. An alternative approach is to use cascaded downconversion: by sending photons produced with downconversion into a second nonlinear crystal to be downconverted again, it is possible to produce photon triplets directly. In this talk, I will present work from my group and others exploring this novel process and discuss current research directions aiming to make cascaded downconversion more useful for state generation and beyond.
From Photon Pairs to Photon Triplets: Exploring Cascaded Down Conversion and its Applications
Host: John Sipe