Abstract
The light or acoustic waves that enable quantum information to be propagated from one point to another : we speak of qubit " flying ". This second lecture will introduce the formalism used to describe these quantum systems - based on the quantum harmonic oscillator. We'll then look at how to encode information about light, exploiting either single photons or components of the electromagnetic field. We will present the main techniques for characterizing these quantum states, briefly describing key technological developments such as single-photon detectors. Finally, we'll look at techniques for measuring entanglement, using the example of two photons.
