Levitated nanoparticles as non-equilibrium memories: experimental verification of the generalised Landauer’s principle

Optical levitation of nanoscale particles promises to become an outstanding platform for experiments in force sensing and in the foundations of quantum physics and stochastic thermodynamics. Most of the experiments till now, however, have hardly made use of the extraordinary versatility of optical micromanipulation technology. Here, we present a novel optical holographic, SLM enabled, trapping platform that levitates a nanosphere in vacuum in a fully controllable double-well potential.
We show the versatility of our platform by verifying a generalised version of Landauer’s principle, where a logical memory is encoded in the position of the particle in the double-well, and the initial state is prepared in an out-of-equilibrium classically-squeezed condition. We infer produced work and heat over many repetitions of the protocols, and we observe that such state preparation greatly reduces the energy cost to erase the memory, allowing it in principle to be made negative [1].
Our results pave the way to fully customizable vacuum optical trapping in arbitrary potentials and opens up to the study of non-linearities in ground-state cooled particles.

[1] M. Konopik et al, EPL, 131, 6 (2020)