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Title: Energy‐Efficient Ultrafast SOT‐MRAMs Based on Low‐Resistivity Spin Hall Metal Au 0.25 Pt 0.75

Many key electronic technologies (e.g., large‐scale computing, machine learning, and superconducting electronics) require new memories that are at the same time fast, reliable, energy‐efficient, and of low‐impedance, which has remained a challenge. Nonvolatile magnetoresistive random access memories (MRAMs) driven by spin–orbit torques (SOTs) have promise to be faster and more energy‐efficient than conventional semiconductor and spin‐transfer‐torque magnetic memories. It is reported that the spin Hall effect of low‐resistivity Au0.25Pt0.75thin films enables ultrafast antidamping‐torque switching of SOT‐MRAM devices for current pulse widths as short as 200 ps. If combined with industrial‐quality lithography and already‐demonstrated interfacial engineering, an optimized MRAM cell based on Au0.25Pt0.75can have energy‐efficient, ultrafast, and reliable switching, for example, a write energy of <1 fJ (<50 fJ) for write error rate of 50% (<10−5) for 1 ns pulses. The antidamping torque switching of the Au0.25Pt0.75devices is ten times faster than expected from a rigid macrospin model, most likely because of the fast micromagnetics due to the enhanced nonuniformity within the free layer. The feasibility of Au0.25Pt0.75‐based SOT‐MRAMs as a candidate for ultrafast, reliable, energy‐efficient, low‐impedance, and unlimited‐endurance memory is demonstrated.

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Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Electronic Materials
Medium: X
Sponsoring Org:
National Science Foundation
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