# Playing with quantum light

## Marco Bellini

**Mo, 9 May 2016, at 10:00. Aula Querzoli**

Light is the perfect candidate for exploring and exploiting the quantum properties of nature. It can be used to test fundamental quantum rules and to beat the conventional classical limits in measurement precision, communication security, or computational power. In order to do so, one is generally required to produce and characterize nonclassical light states with single-photon-level accuracies.

In this lecture, I will introduce the basic concepts and provide real experimental examples of the generation, manipulation and analysis of quantum states of light. I will start with an introduction of the fundamental concepts and with a description of the basic experimental tools, such as parametric down-conversion for the production of nonclassical light and balanced homodyne detection for its detection. In particular, I will concentrate on experiments dealing with the controlled addition and subtraction of single photons and on the coherent superposition of such quantum operations.

Then, I will present some advanced applications of these tools to a variety of nonclassical states of light, with illustrations of the most fundamental concepts of quantum mechanics at play in the lab.

[1] A. Zavatta, S. Viciani and M. Bellini, Science, 306, 660 (2004)

[2] V. Parigi, A. Zavatta, M.S. Kim, and M. Bellini, Science, 317, 1890-1893 (2007)