Superconducting Quantum Point Contacts
  We review our experiments on the electronic transport properties of atomic contacts between metallic electrodes, in particular superconducting ones. Despite ignorance of the exact atomic configuration, these ultimate quantum point contacts can be manipulated and well characterized in-situ. They allow performing fundamental tests of the scattering theory of quantum transport. In particular, we discuss the case of the Josephson effect. 
L. Bretheau, \c{C}. Girit, L. Tosi, M. Goffman, P. Joyez, H. Pothier,   D. Esteve, and C. Urbina
cond-mat.mes-hall cond-mat.supr-con