Our research infrastructures lie in one site located at the ENSTA-Yvette research centre where experimental sites and offices are spread over a total surface of 5200 m². LOA provides uniqueness instrumentations in the field of ultrafast laser-plasmas with laser duration down to an optical cycle & high rep rate, multi-beams synchronized at the femtosecond time-scale (up to 5 in Salle Jaune for example), dedicated topics and fixed experimental set-up, or mobile Terawatt ultrafast lasers.o.