University of Paris-Sud (University of Paris XI) is regarded as one of the largest and most renowned French universities, especially in fields of science. It is ranked the 1st in France, 7th in Europe and 40th worldwide by the Academic Ranking of World Universities. It is also known for its specialised labs and Noble Prize winners who work there.
University of Paris-Sud comprises 104 research units, with about 30,000 students currently enrolled. It was originally part of the University of Paris, which has split into several universities. After World War II, the rapid growth of nuclear physics and chemistry meant that research needed more and more powerful accelerators, which required large areas. Now it is distributed among several campuses in the southern suburb of Paris. They host great many laboratories, some of which are considered to be among the top ones in the world. These include the laboratories in particle physics, nuclear physics, astrophysics, atomic physics and molecular physics, condensed matter physics, theoretical physics, electronics and nanoscience, as well as nanotechnology.