14:45 〜 15:00
▼ [20p-E216-6] Tailoring domain-wall motion and magnetization in synthetic antiferromagnets through ionic liquid gating
キーワード：domain wall motion, ionic liquid gating
Racetrack memory devices based on highly packed magnetic domain wall motions (DWM) in perpendicular magnetized heterostructures have been intensely researched since its potential for realizing next generation memory devices with high efficiency, high speed and low energy consumption. These DWM will have a Néel wall structure and could be well motivated with Spin Orbit torque originating from the interfacial Spin Orbit coupling. A synthetic antiferromagnetic (SAF) structure composed two magnetic sub-layers exchange coupled through an antiferromagnetic spacing layer could further increase the capacity and efficiency of the racetrack devices thanks to its low remnant magnetization and strong exchange coupling. The exchange coupling not only stabilizes the Néel wall configuration but also gives rise to an exchange-coupling torque closely related to the exchange coupling strength as an additional driving force for a more efficient DWM.
In this work, we show a non-volatile ionic liquid (IL) gating effect that the DWM velocity in SAF structure can be reversibly manipulated up to 300%. Such a large change in domain wall motion velocity is caused by the IL gating induced modification of interlayer exchange coupling, as well as remnant magnetization ratio. Furthermore, by using high resolution transmission electron microscopy and energy dispersive x-ray detector technique, we confirm the above mentioned substantial changes to be induced by the metal ion migration rather than the electrostatic changes of carrier density. This work not only provides a novel understanding for the underling mechanism of IL gating on metal heterostructures, but also paves a way for dynamic manipulation of spintronic devices.
In this work, we show a non-volatile ionic liquid (IL) gating effect that the DWM velocity in SAF structure can be reversibly manipulated up to 300%. Such a large change in domain wall motion velocity is caused by the IL gating induced modification of interlayer exchange coupling, as well as remnant magnetization ratio. Furthermore, by using high resolution transmission electron microscopy and energy dispersive x-ray detector technique, we confirm the above mentioned substantial changes to be induced by the metal ion migration rather than the electrostatic changes of carrier density. This work not only provides a novel understanding for the underling mechanism of IL gating on metal heterostructures, but also paves a way for dynamic manipulation of spintronic devices.