• 054353 - QUANTUM OPTICS AND INFORMATION

This course provides an introductory overview on the basic principles of quantum optics, their use to understand the fundamental mechanisms of light-matter interaction and the possibility to exploit these concepts to manipulate information in a completely new way as in quantum communication and quantum computation protocols. The course is conceived as a starting point for more specialistic studies and, in general, as a cultural survey over quantum technologies that will be at the basis of the future information society.

Knowledge and understanding (DD1)

Attending the lectures and passing the exam will allow the student to:

- Understand the physical basis of quantum optical phenomena;

- Learn the fundamental mechanisms governing light-matter interaction; 

- Learn the principles and the main protocols of quantum information.

Apply knowledge and understanding (DD2)

The student will be able to apply the basic knowledge described above to:

- explain the operating principles of some prototypal optical devices developed for quantum information;

- deepen the understanding of physical phenomena encountered in other courses with a new perspective;

- follow with greater awareness the new trends in the high-tech market (from quantum communications to quantum computing) dealing with quantum technologies.

Communication skills (DD4)

The completely oral exam and the possibility to present one topic at the student's choice before the general discussion, will force the student to learn how to organize and deliver an effective scientific presentation. 

Lifelong learning skills (DD5)

Students will be capable to autonomously follow with greater awareness the new trends in the high-tech market dealing with quantum technologies (from quantum communications to quantum computing).

Quantum optics

1. Photon Statistics.
2. Photon bunching and antibunching: Hanbury-Brown and Twiss interferometer.
3. Quantization of the elecromagnetic field: from Maxwell's equations to quantum operators.
4. Quantum states of light: Photon number states, coherent light and squeezed light.
5. Quantum description of an optical beam splitter.
6. Resonant light – atom interactions: Jaynes-Cummings model, absorption, stimulated and spontaneous emission.
7. Atoms in optical cavities: dressed states, Rabi oscillations, collapse and revivals.

Quantum Information

8. Single photon sources.
9. Quantification of photon indistinguishability by the Hong-Ou-Mandel effect.
10. Entangled states: generation by spontaneous parametric down conversion.
11. Einstein-Podolsky-Rosen paradox and Bell’s theorem
12. Quantum teleportation.
13. Quantum cryptography: BB84 protocol
14. Qubits and quantum computing: Deutsch's algorithm, Grover's algorithm, Shor's algorithm

No pre-requisites are formally requested. However, a basic understanding of quantum mechanics and his formalism may be useful.

The exam consists in an oral discussion. The discussion will be based on 2-3 open questions, each on a different topic. The student can start with a presentation on a topic of the course at his choice.

The aim of the discussion is to ascertain:

- the understanding of the physical basis of quantum optics and information;

- the knowledge of the definitions, theorems and general concepts related to quantum optics and quantum information;

- the capability to discuss, both qualitatively and quantitatively, the quantum physical models and protocols relevant for the course.

The course will be concentrated in the first half of the second semester. There will be the possibility to take the exam in the weeks following the end of the course, in addition to the usual five dates for the exams along the year (two in the summer session, one in the autumn session and two in the winter session).

This book covers most of the course with a rigorous approach. It requires a good background in quantum mechanics. Sometimes it lacks of physical intuition and thus may be a tough start for those who do not have a solid background.

This book is a very good introduction to the field. It is particularly suggested to those who are not too familiar with quantum mechanics. It covers most of the course, although often with a simplified treatment.