Operating micromechanical logic gates below kBT: Physical vs logical reversibility

In modern computers computation is performed by assembling together sets of logic gates made by transistors acting as logic switches. The scaling of transistor dimensions allowed a continuous increase of performance accompanied by an increase of heat production. The latter will represent a road-block for the development of future computing devices. Landauer theorized on the minimum heat production required to perform a reset operation of one bit [1], i.e. QL=kBTlog2, a result that has been recently experimentally shown by S. Ciliberto et al [2]. However, a question that is still somehow controversial [3-5] is the following: is there a finite minimum amount of energy required to operate an irreversible logic gate?