Highly reliable low-energy writing of bits in non-volatile multiferroic memory based on 180-degree magnetization switching with voltage-generated stress

TL;DR

This paper presents a novel strain-based method for 180-degree magnetization switching in multiferroic nanomagnets, enabling ultra-energy-efficient, fast, and reliable non-volatile memory writing at room temperature.

Contribution

It introduces a scheme for complete 180-degree magnetization rotation using strain, overcoming previous limitations of partial rotation methods.

Findings

Energy dissipation less than 6200 kT per bit

Write error probability below 10^-6

Write time approximately 1 nanosecond

Abstract

Rotating the magnetization of a magnetostrictive nanomagnet with electrically generated mechanical strain dissipates miniscule amount of energy compared to any other rotation method and would have been the ideal method to write bits in nonvolatile magnetic memory, except strain cannot ordinarily rotate the magnetization of magnet by more than 90 degrees and "flip" it. Here, we describe a scheme to achieve complete 180 degree rotation of the magnetization of a nanomagnet with strain that will enable writing of binary bits in non-volatile magnetic memory implemented with magneto-tunneling junctions whose soft layers are two-phase magnetostrictive/piezoelectric multiferroics. At room temperature, this writing method results in: (1) energy dissipation < 6200 kT per bit, (2) write error probability < 10^-6, (3) write time of ~ 1 ns, and (4) low read error. This could potentially lead to a new genre of non-volatile memory that is extremely reliable, fast and, at the same time, ultra-energy-efficient.