20-nm magnetic domain wall motion memory with ultralow-power operation

Abstract

We study the write and retention properties of magnetic domain wall (DW)-motion memory devices with the dimensions down to 20 nm. We find that the write current and time are scaled along with device size while sufficient thermal stability and low error rate are maintained. As a result, ultralow-power (a few fJ) and reliable operation is possible even at reduced dimensions.

STT-SNN: A Spin-Transfer-Torque Based Soft-Limiting Non-Linear Neuron for Low-Power Artificial Neural Networks

“…3a. DW can be moved along a magnetic nanostrip using current injection along the DWM strip [9][10][11]. Hence, the spin polarity of the DWM strip at a given location can be switched, depending upon the polarity of its adjacent domains and direction of current flow.…”

“…Therefore, in order to translate the ANN algorithmic models into powerful, yet energyefficient cognitive computing hardware, computing devices beyond CMOS are being explored. Recent experiments on spin-torque devices have demonstrated high speed switching of nano-magnets with small currents [9][10][11][12]. Such magnetometallic devices can operate at ultra-low terminal voltages and can implement current-mode summation and non-linear operations required by an artificial neuron.…”

A compact low-power nonvolatile flip-flop using domain-wall-motion-device-based single-ended structure

“…The parameters for the STT-MTJ device and the DWM device are summarized in Table I, that are estimated from 100 nm? junction size with measurement results in [8,9,14]. Note that, I P ÀAP and I AP ÀP are the amounts of write current to program desired data in 2 ns.…”

“…In this paper, an NV-FF is proposed using a domain-wall motion (DWM) device [8,9] together with single-ended voltage sensing [10]. Since the read current path is separated from the write current path in the DWM device, both the write driver and the sense amplifier can be optimized independently with no read disturbance.…”

“…1(a) shows the device structure of a DWM device [8,9]. The tunnel barrier and the reference layer are stacked on the DWM region and an MTJ is formed.…”