Nanomagnetic logic: compact modeling of field-coupled computing devices for system investigations

Abstract

In this paper we investigate error rates of nanomagnetic logic devices with perpendicular magnetization by compact modeling. Two different types of nanomagnets for information propagation and logic computing are introduced. The switching behavior of field-coupled nanomagnets is measured and analyzed. A compact model is derived from physics and experimental results are applied to the magnetic compact model. General requirements for fabrication parameters and clocking fields for reliable operation are extracted. We perform simulations and measurements on single devices to demonstrate the accuracy of the macromodel. Simulations on complex systems show that the error rate of a field-coupled magnetic system strongly depends on the variation of the switching field and the strength of the coupling field between the nanomagnets. The error rate of a 1-bit full adder is investigated for varying dot parameters. The results demonstrate the importance of fast simulation tools for investigations on the design of nanomagnetic computing devices and systems.

Manipulation of Magnetic Solitons on Odd-Numbered Macrospin Rings

“…We follow similar model studies and implement this as a distribution in the spins' switching behavior. 4,36 For a given realization, we generate the values C i from a psuedo-Gaussian distribution with mean = 1 and standard deviation σ. Studies show that this provides a good approximation for the behavior of coupled nanomagnet vertex systems, accounting for a combination of possible property distributions.…”

1-Bit Full Adder in Perpendicular Nanomagnetic Logic using a Novel 5-Input Majority Gate

“…For instance, the coupling field can be dramatically increased by enhancing the total magnetic moment or reducing the distance between the inputs and the ANC according to eq.3. Simulations using compact modeling [20] show, that the coupling of each input has to be increased to C x = 60 Oe to reduce the error rate to e < 10 −3 . Consequently, distances between inputs and ANCs have to be reduced to d < 20 nm to provide definite and reliable computation using TLG-based pNML.…”

“…Due to switching field distributions (SFDs) caused by the influence of thermal noise and fabrication variations of the ANC from dot to dot, the residual clocking window for complex NML circuits is noticeably reduced [15,[18][19][20]. Hence, it is fundamental to precisely control the location and the strength of the ANC by size and dose of the partial FIB irradiation [5,9].…”

Design of 3D nanomagnetic logic circuits: A full-adder case study

“…978-3-9815370-2-4/DATE14/ c 2014 EDAA input combinations) when tested via micromagnetic simulation with a uniform clocking methodology. As it is generally wellaccepted that there is good correlation between micromagnetic simulations and experimental results (e.g., [10]), outputs from our design methodology can serve as initial fabrication targets for experimental verification and testing.…”