Professor Joachain has been a visiting professor in several universities and laboratories in Europe and the United States, in particular at the University of California, Berkeley and the Lawrence Berkeley Laboratory, the Université Pierre et Marie Curie (Paris VI), the University of Rome “La Sapienza” and the Max Planck Institute for Quantum Optics in Garching.
He has co-edited four books : 1) "Atomic and Molecular Physics of Controlled Thermonuclear Fusion"(with D.E.
3) "Atoms, Solids and Plasmas in Super-Intense Laser Fields" (with D. Batani, S. Martellucci and A.N.
4) "Atoms and Plasmas in Super-Intense Laser Fields" (with D. Batani and S. Martellucci), Conference Proceedings, Volume 88, Italian Physical Society, Bologna (2004).
He is also the author of hundred and forty-seven research articles and forty-five review articles in theoretical physics, devoted mainly to quantum collision theory with applications to atomic, nuclear and high-energy processes and to the theory of high-intensity laser-atom interactions.
He was President of the Belgian Physical Society from 1987 to 1989 and of the “Institut des Hautes Etudes” of Belgium from 2006 to 2011.