Ionic-liquid gating on a functional thin film with a low voltage has drawn a lot of attention due to rich chemical, electronic, and magnetic phenomena at the interface. Here, a key challenge in quantitative determination of voltage-controlled magnetic anisotropy (VCMA) in Au/[DEME] [TFSI] /Co field-effect transistor heterostructures is addressed. The magnetic anisotropy change as response to the gating voltage is precisely detected by in situ electron spin resonance measurements. A reversible change of magnetic anisotropy up to 219 Oe is achieved with a low gating voltage of 1.5 V at room temperature, corresponding to a record high VCMA coefficient of ≈146 Oe V . Two gating effects, the electrostatic doping and electrochemical reaction, are distinguished at various gating voltage regions, as confirmed by X-ray photoelectron spectroscopy and atomic force microscopy experiments. This work shows a unique ionic-liquid-gating system for strong interfacial magnetoelectric coupling with many practical advantages, paving the way toward ion-liquid-gating spintronic/electronic devices.

One of the central challenges in realizing multiferroics-based magnetoelectric memories is to switch perpendicular magnetic anisotropy (PMA) with a control voltage. In this study, we demonstrate electrical flipping of magnetization between the out-of-plane and the in-plane directions in (Co/Pt)/(011) Pb(MgNb)O-PbTiO multiferroic heterostructures through a voltage-controllable spin reorientation transition (SRT). The SRT onset temperature can be dramatically suppressed at least 200 K by applying an electric field, accompanied by a giant electric-field-induced effective magnetic anisotropy field (ΔH) up to 1100 Oe at 100 K. In comparison with conventional strain-mediated magnetoelastic coupling that provides a ΔH of only 110 Oe, that enormous effective field is mainly related to the interface effect of electric field modification of spin-orbit coupling from Co/Pt interfacial hybridization via strain. Moreover, electric field control of SRT is also achieved at room temperature, resulting in a ΔH of nearly 550 Oe. In addition, ferroelastically nonvolatile switching of PMA has been demonstrated in this system. E-field control of PMA and SRT in multiferroic heterostructures not only provides a platform to study strain effect and interfacial effect on magnetic anisotropy of the ultrathin ferromagnetic films but also enables the realization of power efficient PMA magnetoelectric and spintronic devices.

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Electric field control of dynamic spin interactions is promising to break through the limitation of the magnetostatic interaction based magnetoelectric (ME) effect. In this work, electric field control of the two-magnon scattering (TMS) effect excited by in-plane lattice rotation has been demonstrated in a LaSrMnO (LSMO)/Pb(MnNb)-PbTiO (PMN-PT) (011) multiferroic heterostructure. Compared with the conventional strain-mediated ME effect, a giant enhancement of ME effect up to 950% at the TMS critical angle is precisely determined by angular resolution of the ferromagnetic resonance (FMR) measurement. Particularly, a large electric field modulation of magnetic anisotropy (464 Oe) and FMR line width (401 Oe) is achieved at 173 K. The electric-field-controllable TMS effect and its correlated ME effect have been explained by electric field modulation of the planar spin interactions triggered by spin-lattice coupling. The enhancement of the ME effect at various temperatures and spin dynamics control are promising paradigms for next-generation voltage-tunable spintronic devices.

BackgroundKIAA1199 was upregulated in diverse cancers, but the association of KIAA1199 with gastric cancer (GC), the biological role of KIAA1199 in GC cells and the related molecular mechanisms remain to be elucidated.MethodsKIAA1199 expression was analysed by reverse transcription-polymerase chain reaction assay (RT-PCR) and immunohistochemistry (IHC) in GC patient tissue. The small hairpin RNA (shRNA) was applied for the knockdown of endogenous KIAA1199 in NCI-N87 and AGS cells. MTT, colony formation, scratch wounding migration, transwell chamber migration and invasion assays were employed respectively to investigate the role of KIAA1199 in GC cells. The potential signaling pathway of KIAA1199 induced migration and invasion was detected.ResultsKIAA1199 was upregulated in GC tissue and was an essential independent marker for poor prognosis. Knockdown KIAA1199 suppressed the proliferation, migration and invasion in GC cells. KIAA1199 stimulated the Wnt/β-catenin signaling pathway and the enzymatic activity of matrix metalloproteinase (MMP) family members and thus accelerated the epithelial-to-mesenchymal transition (EMT) progression in GC cells.ConclusionThese findings demonstrated that KIAA1199 was upregulated in GC tissue and associated with worse clinical outcomes in GC, and KIAA1199 acted as an oncogene by promoting migration and invasion through the enhancement of Wnt/β-catenin signaling pathway and MMPs mediated EMT progression in GC cells.