Stochastic thermodynamics of finite-tape information ratchet

In this paper, we explore into the stochastic thermodynamics of a finite-tape information ratchet system. By determining the entropy production of the tape-ratchet system, we derive the information processing second law obeyed by the system. We found that the entropy production takes the form of the non-adiabatic component in both the transient and stationary regime, with the adiabatic component vanishes. The out-of-equilibrium stochastic behaviour is thus driven by non-adiabatic entropy production, with the occurrence of spontaneous relaxation from nonequilibrium initial state and the switching operation of the finite-tape information ratchet system. The observed nonequilibrium processes include (1) work extraction by assimilating excess heat from the heat reservoir when the information ratchet functions as an engine, or (2) dissipating work as excess heat into the heat reservoir when the information ratchet acts as a Landauer eraser. In particular, we observe the phenomenon of irreversible work conversion into excess heat as the information ratchet operates in the nonequilibrium stationary state.