Giant Electric Field Tuning of Magnetic Properties in Multiferroic Ferrite/Ferroelectric Heterostructures

Abstract

Multiferroic heterostructures of Fe3O4/PZT (lead zirconium titanate), Fe3O4/PMN‐PT (lead magnesium niobate‐lead titanate) and Fe3O4/PZN‐PT (lead zinc niobate‐lead titanate) are prepared by spin‐spray depositing Fe3O4 ferrite film on ferroelectric PZT, PMN‐PT and PZN‐PT substrates at a low temperature of 90 °C. Strong magnetoelectric coupling (ME) and giant microwave tunability are demonstrated by a electrostatic field induced magnetic anisotropic field change in these heterostructures. A high electrostatically tunable ferromagnetic resonance (FMR) field shift up to 600 Oe, corresponding to a large microwave ME coefficient of 67 Oe cm kV−1, is observed in Fe3O4/PMN‐PT heterostructures. A record‐high electrostatically tunable FMR field range of 860 Oe with a linewidth of 330–380 Oe is demonstrated in Fe3O4/PZN‐PT heterostructure, corresponding to a ME coefficient of 108 Oe cm kV−1. Static ME interaction is also investigated and a maximum electric field induced squareness ratio change of 40% is observed in Fe3O4/PZN‐PT. In addition, a new concept that the external magnetic orientation and the electric field cooperate to determine microwave magnetic tunability is brought forth to significantly enhance the microwave tunable range up to 1000 Oe. These low temperature synthesized multiferroic heterostructures exhibiting giant electrostatically induced tunable magnetic resonance field at microwave frequencies provide great opportunities for electrostatically tunable microwave multiferroic devices.

Film size-dependent voltage-modulated magnetism in multiferroic heterostructures

“…The magnetization and/or the magnetic domain can also be rotated by 90 • in the film plane upon applying anisotropic in-plane piezostrains [25,26,56]. Consider a (001) CFO film attached to a (001) lead zirconate niobate-lead titanate (PZN-PT) layer with ultrahigh piezoelectric response [87].…”

Coherent piezoelectric strain transfer to thick epitaxial ferromagnetic films with large lattice mismatch

“…The most commonly used piezoelectric substrate is (1-x)Pb(Mg 1/3 Nb 2/3 )O 3 -xPbTiO 3 , which is a well-known relaxor ferroelectric material with excellent electromechanical and piezoelectric properties for compositions near the morphotropic phase 3 boundary (0.25  x  0.35) [12]. Piezoelectric strain transfer from PMN-PT substrates has, for example, been used to tune the magnetic properties of manganite [13,14], ferrite [15][16][17][18][19], and metallic magnetic films [20][21][22][23], to alter the electrical resistance of magnetic oxides [13,18,[24][25][26], to demonstrate straincontrolled light emission from semiconductor heterostructures [27,28], and to tailor the properties of graphene [29]. In addition, strain-modulation of magnetic properties on a microscopic scale has recently been demonstrated in ferromagnetic-ferroelectric hybrids [30][31][32], which has opened new ways to electric control of ferromagnetic domain formation and magnetic domain wall motion [33,34].…”

Magnetoelectric coupling across the interface of multiferroic nanocomposites

“…Liu et al [28] deposited the Fe 3 O 4 on a variety of piezoelectric substrates such as PZT, Pb(Zn 1/3 Nb 2/3 )O 3−x PbTiO 3 (PZN-PT) and PMN-PT by spin-spray deposition. The microwave ME coefficient of the composite was measured as 108 Oe cm kV −1 on the films grown on PZN-PT.…”