Logic circuit prototypes for three-terminal magnetic tunnel junctions with mobile domain walls

Abstract

Spintronic computing promises superior energy efficiency and nonvolatility compared to conventional field-effect transistor logic. But, it has proven difficult to realize spintronic circuits with a versatile, scalable device design that is adaptable to emerging material physics. Here we present prototypes of a logic device that encode information in the position of a magnetic domain wall in a ferromagnetic wire. We show that a single three-terminal device can perform inverter and buffer operations. We demonstrate one device can drive two subsequent gates and logic propagation in a circuit of three inverters. This prototype demonstration shows that magnetic domain wall logic devices have the necessary characteristics for future computing, including nonlinearity, gain, cascadability, and room temperature operation.

Magnetic logic based on diode-assisted magnetoresistance

“…[2][3][4][5][6][7][8][9][10][11][12][13][14][15] Especially, due to the compatibility with conventional charge-based device, magnetic logic in magnetoelectronics arouses profound attentions. [5][6][7][8][9][10][11][12][13][14][15] Benefit from the extra dimension of spin, magnetic logic has the attractive features of reconfigurable logic operation and built-in non-volatile memory. Practical proposals of magnetic logic in magnetoelectronics are mainly focusing on spin-dependent transport in magnetic materials known as spin-based logic, 5,[7][8][9][10][11]13,15 and asymmetry magnetoresistance effect in non-magnetic semiconductors known as magnetic-field-based logic.…”

“…[5][6][7][8][9][10][11][12][13][14][15] Benefit from the extra dimension of spin, magnetic logic has the attractive features of reconfigurable logic operation and built-in non-volatile memory. Practical proposals of magnetic logic in magnetoelectronics are mainly focusing on spin-dependent transport in magnetic materials known as spin-based logic, 5,[7][8][9][10][11]13,15 and asymmetry magnetoresistance effect in non-magnetic semiconductors known as magnetic-field-based logic. 6,12,14 For spin-based logic, logic input is stored in the magnetization and logic operation between magnetic bits is achieved through spin-dependent transport.…”

Angular Dependence of Magnetization Reversal in Microwire Studied by MOKE

“…domain-wall based logic devices or magnetic memories [1,2]. Classically, magnetic properties of microwires are measured by induction methods [3,4].…”

Magnetization reversal in ferromagnetic wires patterned with antiferromagnetic gratings

“…[11][12][13][14] In general, exchange bias and the blocking temperature decrease with decreasing dimensions, which has been attributed to formation of spin glass-like regions with weaker exchange bias at the edges of the patterned features. 17,18 Structures in which the FM and AFM layer are patterned into different dimensions [20][21][22][23][24] are much less well studied, even though FM layers with local regions of exchange bias may be useful in controlling domain walls in racetrack memory and logic devices 23 and in magnetic bit encoders 25 and mangnonic crystals. 26,27 For example, the magnetic properties of a continuous FM film partly covered with patterned AFM regions depend on the dimensions of the AFM and the strength of the exchange bias within the pinned regions, as shown in NiFe/FeMn 24 and NiFe/IrMn, 28 and Co films with O implantation showed local EB due to the formation of CoO in the implanted regions.…”

“…The one-step to two-step transition with increasing dimensions was also found in NiFe continuous films overlaid with IrMn stripes. This behavior is relevant to applications such as domain wall memory or logic devices consisting of magnetic wires with pinned regions, 22 in which local exchange bias can control the location and movement of domain walls.…”