Low-field Switching Four-state Nonvolatile Memory Based on Multiferroic Tunnel Junctions

Abstract

Multiferroic tunneling junction based four-state non-volatile memories are very promising for future memory industry since this kind of memories hold the advantages of not only the higher density by scaling down memory cell but also the function of magnetically written and electrically reading. In this work, we demonstrate a success of this four-state memory in a material system of NiFe/BaTiO3/La0.7Sr0.3MnO3 with improved memory characteristics such as lower switching field and larger tunneling magnetoresistance (TMR). Ferroelectric switching induced resistive change memory with OFF/ON ratio of 16 and 0.3% TMR effect have been achieved in this multiferroic tunneling structure.

Solid-State Synapse Based on Magnetoelectrically Coupled Memristor

“…Artificial multiferroic tunnel junctions (MFTJs), employing ferroelectric barriers in MTJs or ferromagnetic electrodes in FTJs, provide not only the combined functionalities of MTJs and FTJs to achieve multistate devices − but also promising applications utilizing the magnetoelectric coupling at the ferromagnetic/ferroelectric interfaces. − The interfacial spin polarization and the TMR can be tuned via ferroelectric polarization reversal. − Using an MFTJ as a memristor, one can manipulate the resistance by modifying not only magnetic states but also ferroelectric domains, which enhances the operability in the plasticity of artificial synapses based on MFTJs. Furthermore, from the point of view of magnetoelectric coupling, it could be expected that for a memristor based on MFTJs, the magnetic states of electrodes may affect the ferroelectric memristive behaviors, which can provide a way to emulate the property of different biological synaptic morphologies.…”

Quasi-Monodisperse Transition-Metal-Doped BaTiO3 (M = Cr, Mn, Fe, Co) Colloidal Nanocrystals with Multiferroic Properties

“…BaTiO 3 is an archetypal ferroelectric perovskite that exhibits polar ordering at room temperature and has been used in many technological applications including data storage, energy conversion, electronics, sensing, catalysis, and nonlinear optics. − In conventional nonvolatile memory devices, binary information is encoded as “0s” and “1s” by using Boolean algebra, which exploits the two extreme orientations (upward and downward) of the magnetic or electrical dipoles. With the increasing need for portable storage devices with a high areal density, low-power consumption, and fast access times, the design of four-state logic memory elements has garnered an increasing interest. , Such multiple-state memories use a special class of materials known as multiferroics , in which the magnetization M and the dielectric polarization P coexist in the same phase . This unique ability to present at least two ferroic order parameters makes multiferroics prime candidates not only for data storage, but also in drug delivery, magnetic field sensing, spintronics, and microwave technology. − Previous studies focused exclusively on BiFeO 3 -based perovskite materials, which exhibit multiferroism at room temperature, but the cross coupling between the two order parameters (magnetization and dielectric polarization) is generally weak.…”

“…With the increasing need for portable storage devices with a high areal density, low-power consumption, and fast access times, the design of four-state logic memory elements has garnered an increasing interest. 5,6 Such multiple-state memories use a special class of materials known as multiferroics 7,8 in which the magnetization M and the dielectric polarization P coexist in the same phase. 9 This unique ability to present at least two ferroic order parameters makes multiferroics prime candidates not only for data storage, but also in drug delivery, magnetic field sensing, spintronics, and microwave technology.…”

Laser-Induced Graphene from Wood Impregnated with Metal Salts and Use in Electrocatalysis

“…The magnetization curve of cedar-LIG-NiFe as a function of the applied magnetic field was measured at room temperature and depicted in Figure a. Compared to graphene with a chaotic zigzag magnetization pattern and no obvious magnetic features, cedar-LIG-NiFe presented typical ferromagnetic behavior as confirmed by the magnetization hysteresis loop, exhibiting a saturation magnetization ( M s ) of 16.8 emu g –1 and coercivity ( H c ) of 155 Oe, respectively. Because of the dielectric performance of graphene, magnetic characteristic of ferromagnetic metal nanocrystals, and synergistic effects between these two components, EMI shielding effectiveness of cedar-LIG-NiFe/paraffin nanocomposite reaches up to 54 dB, whereas target EMI shielding effectiveness for commercial application is only 20 dB .…”