Switching Energy of Ferromagnetic Logic Bits

TL;DR

This paper analyzes the energy dissipation during the switching of ferromagnetic logic bits, revealing how ramp time affects energy loss and providing insights into their potential for scalable, high-frequency logic circuits.

Contribution

It provides a generic analytical framework for switching energy in ferromagnetic logic bits, highlighting the impact of pulse ramp time and offering design guidance for scalable magnetic logic circuits.

Findings

Switching energy drops significantly when pulse ramp time exceeds a critical value.

A single equation describes switching energy in both fast and slow regimes.

Nanomagnets can achieve scaling laws similar to CMOS technology.

Abstract

Power dissipation in switching devices is believed to be the single most important roadblock to the continued down scaling of electronic circuits. There is a lot of experimental effort at this time to implement switching circuits based on magnets and it is important to establish power requirements for such circuits and their dependence on various parameters. This paper analyzes switching energy which is dissipated in the switching process of single domain Ferromagnets used as cascadable logic bits. We obtain generic results that can be used for comparison with alternative technologies or guide the design of magnet based switching circuits. Two central results are established. One is that the switching energy drops significantly if the ramp time of an external pulse exceeds a critical time. This drop occurs more rapidly than what is normally expected of adiabatic switching for a capacitor. The other result is that under the switching scheme that allows for logic operations, the switching energy can be described by a single equation in both fast and slow limits. Furthermore, these generic results are used to quantitatively examine the possible operation frequencies and integration densities of these logic bits which show that nanomagnets can have scaling laws similar to CMOS technology.