Computing with Non-equilibrium Ratchets

TL;DR

This paper explores electronic ratchets that generate directed currents without a drain bias, offering energy-efficient computation by reducing static and dynamic dissipation, and enabling adiabatic logic through a novel charging mechanism.

Contribution

It demonstrates how non-equilibrium ratchets can be used to perform universal Boolean logic with potential energy savings and relaxed timing constraints.

Findings

Ratchets can operate as gate-controlled current sources.

Sequence of ratchets can implement universal logic.

Potential for reduced static and dynamic dissipation.

Abstract

Electronic ratchets transduce local spatial asymmetries into directed currents in the absence of a global drain bias, by rectifying temporal signals that reside far from thermal equilibrium. We show that the absence of a drain bias can provide distinct energy advantages for computation, specifically, reducing static dissipation in a logic circuit. Since the ratchet functions as a gate voltage-controlled current source, it also potentially reduces the dynamic dissipation associated with charging/discharging capacitors. In addition, the unique charging mechanism eliminates timing related constraints on logic inputs, in principle allowing for adiabatic charging. We calculate the ratchet currents in classical and quantum limits, and show how a sequence of ratchets can be cascaded to realize universal Boolean logic.