In 2004 Ohtomo and Hwang discovered that the interface between two band insulators, LaAlO3 and SrTiO3, is conducting. This thesis focuses on the properties of the LaAlO3/SrTiO3 interface at the nanoscale. First, we developed a technique to realize conducting wires of nanometric scale in insulating LaAlO3/SrTiO3 interfaces. Then, we investigated the use of an optical technique with nanometric resolution to study the electronic properties of the interface. Finally, we analyzed the electronic transport in conducting nano-devices. This study yields insights on the complementary effect of low-dimension physics and transition metal metal oxides properties. Moreover, a small portion of this work has been dedicated to the study of spintronic effects stemming from the interplay between spin and charge degrees of freedom at the LaAlO3 /SrTiO3 interface.