Fundamental energy limits in the physics of nanomagnetic binary switches

Binary switches are the basic element of modern digital computers. In this paper we consider a magnetic binary switch consisting of a nanodot constituted by a single cylindrical ferromagnetic element with two stable energy minima and perform virtual experiments using numerical simulations based on the micromagnetic approach. The fundamental limits in minimum energy dissipation are discussed presenting two, popularly adopted, switching procedures. We show that the zero-power limit is only attainable with one of the two protocols, which does not involve any irreversible entropy increase. Moreover, the in fl uence of the energy barrier height in the presence of fl uctuations and the role of bit- fl ip errors is quantitatively analyzed.