Cavity QED

 

What is it ?

Cavity QED deals with the simplest situation where the interaction between light and matter can be studied: a simple two level atom interacting with a single electromagnetic mode.


Things really become fascinating when the coupling between the atom and the electromagnetic mode dominates the physics. In this regime, called the strong coupling regime, we are exploring the physics of a coupled light & matter quantum system.


Originally cavity QED experiments have been performed using real atoms and optical or microwave cavities. But not, recent progresses in nanofabrication and a better understanding of superconducting nanocircuits have opened a new way to do cavity QED experiments. This new realm of experiments, called circuit QED, is considered as one of the most promising line of research for quantum information manipulation.

WHY IS IT interesting ?

Because of its conceptual simplicity, cavity QED is one of the best playground for manipulating quantum states. Several groups are actively pursuing this line of research, trying in particular to demonstrate simple quantum algorithms such as the Grover algorithm.


Since real systems cannot be perfectly isolated from their environment, their quantum properties are hidden through decoherence. In strong coupling cavity QED, environmental effects are weak but neverthless present. Cavity QED thus provides a very convenient playground for studying decoherence.


My own work on cavity QED precisely deals with decoherence and the transition from the quantum to the classical world.

Do you want to know more ?

If you are interested by my own work, you should read my papers on the subject.


One of the most complete resource on cavity QED is the Web site maintained by the Cavity QED group of the Ecole Normale Supérieure of Paris. In particular, the lectures by Serge Haroche are a must on the subject!