Conditional entropy and Landauer principle
1 NiPS Laboratory, Dipartimento di Fisica, Universitá degli studi di Perugia - Via Alessandro Pascoli, I-06123 Perugia, Italy
2 INFN, sezione Perugia - I-06100 Perugia, Italy
Received: 28 April 2015
Accepted: 5 August 2015
The Landauer principle describes the minimum heat produced by an information-processing device. Recently a new term has been included in the minimum heat production: it is called conditional entropy and takes into account the microstates content of a given logic state. Usually this term is assumed to be zero in bistable symmetric systems thanks to the strong hypothesis used to derive the Landauer principle. In this paper we show that conditional entropy can be nonzero even for bistable symmetric systems and that it can be expressed as the sum of three different terms related to the probabilistic features of the device. The contribution of the three terms to conditional entropy (and thus to the minimum heat production) is then discussed for the case of bit reset.
PACS: 05.70.Ln – Nonequilibrium and irreversible thermodynamics / 89.70.Cf – Entropy and other measures of information / 05.10.Gg – Stochastic analysis methods (Fokker-Planck, Langevin, etc.)
© EPLA, 2015