Probabilistic work extraction on a classical oscillator beyond the second law

We demonstrate experimentally that, applying optimal protocols which drive the system between two equilibrium states characterized by a free energy difference F, we can maximize the probability of performing the transition between the two states with a work W smaller than F. The second law holds only on average, resulting in the inequality W F. The experiment is performed using an underdamped oscillator evolving in a double-well potential. We show that with a suitable choice of parameters the probability of obtaining trajectories with W F can be larger than 95%. Very fast protocols are a key feature to obtain these results, which are explained in terms of the Jarzynski equality.