Speaker
Description
Single photons provide a compelling entry point into quantum physics, offering a tangible way to explore the fundamental principles of quantization. Creating a single photon is hard. The key way to determine that you have a single photon is to show it can be measured once and only once. The experiment to certify that you have a single photon source was first completed by Nobel Laureate Alain Aspect and his colleague Philippe Grangier through a clever measurement using a beam splitter with a single-photon light source (the calcium cascade light source). Take a photon, create a superposition, and measure it on its two possible paths. Then count how often you see coincidences. Before the modern-day understanding of quantum optics, physicists thought that they could create a single-photon source by just using very dim light from a classical laser. In this talk, we will go over the so-called G2 experiments that verify that dim light is not a single-photon source and will describe the classroom materials we have developed to teach about it in a modern physics course.
