Reversing the Landauer's erasure: information and entropy in mesoscopic thermodynamics

Landauer principle requires that at least k_BTln2 of heat is dissipated into a thermal reservoir at temperature T, when one bit of information is erased from a computing device. It was shown recently that the process of information erasure can be inverted, giving rise to a reversible Maxwell’s demon operating at the limit of thermodynamics efficiency. To extract heat Q from a reservoir and convert it into free energy, such a demon creates the equivalent amount of information, Q/k_BTln2, in its memory. This process was demonstrated experimentally with an electronic Maxwell demon based on the single-electron box, which extracts k_BTln2 of heat per bit of created information that is encoded in a position of an electron in one of the two electrodes of the box [1]. Reversal of the Landauer’s erasure confirms the interpretation of Landauer principle as a manifestation of the second law of thermodynamics demonstrating that information should be regarded as the entropy of a computing device [2].

[1] J.V. Koski, V.F. Maisi, J.P. Pekola, and D.V. Averin, PNAS 111, 13786 (2014).
[2] D.V. Averin and J.P. Pekola, Phys. Stat. Sol. B 254, 1600677 (2017).