Tuning magnetic anisotropy and the damping constant using substrate-induced strain in a FeCo/Pb(Mg1/3Nb2/3)O3-PbTiO3heterostructure

The field angle dependence of the magnetization reversal in 20 nm thick polycrystalline Ni films grown on piezoelectric (0 1 1) [PbMg 1/3 Nb 2/3 O 3 ] 0.68 -[PbTiO 3 ] 0.32 (PMN-PT) substrates is analysed quantitatively to study the magnetic anisotropy induced in the film by poling the piezosubstrate. While the PMN-PT is in the unpoled state, the magnetization reversal is almost isotropic as expected from the polycrystalline nature of the film and corresponding to an orientation ratio (OR) of 1.2. The orientation ratio is obtained by fitting the angular dependence of normalized remanent magnetization to an adapted Stoner-Wohlfarth relation. Upon poling the piezosubstrate, a strong uniaxial anisotropy, whose hard axis is oriented along the [1 0 0] direction of the PMN-PT, is induced, yielding an OR of 3.1. The angular dependence of the coercivity for the poled state is found to consist of a strong increase for increasing field angles away from the easy axis direction and of a sharp decrease for angles close to the hard direction. It is best described by a two-phase model, implying that the magnetization reversal is determined by both, coherent rotation of the magnetic moments, according to the Stoner-Wohlfarth model, and the gradual displacement of the domain walls in obedience to the Kondorsky model.

Section: Resultsmentioning

confidence: 82%

Quantitative analysis of magnetization reversal in Ni thin films on unpoled and poled (0 1 1) [PbMg_1/3Nb_2/3O₃]_0.68–[PbTiO₃]_0.32piezoelectric substrates

Tkach

Kehlberger

Büttner

et al. 2016

“…The normalised remnant magnetisation was measured as a function of angle ( Fig. 2d) and fitted with the following equation [6]:…”

Section: Resultsmentioning

confidence: 99%

Artificial multiferroic structures using soft magnetostrictive bilayers on Pb(Mg_1/3Nb_2/3)–PbTiO₃

Miskevich¹,

Alshammari²,

Yang³

et al. 2018

“…Although there have been a number of works studying the electric voltage manipulation of magnetization switching and magn etic anisotropy in FM/FE heterostructures as mentioned above, the electric voltage controlled magnetic damping is rarely studied. The electric field modulated damping constant was previously investigated in CoFeB/MgO and its MTJ structures [42,43], as well as FeCo/PMN-PT heterostructure [23], but the observed phenomenon was not consistent. Yang et al reported that only the extrinsic damping constant for FeCo/PMN-PT heterostructure can be reduced via substrate induced piezoelectric effect while the intrinsic damping constant was not by employing ferromagnetic resonance (FMR) technique [23].…”

Section: Introductionmentioning

confidence: 97%

“…The electric field modulated damping constant was previously investigated in CoFeB/MgO and its MTJ structures [42,43], as well as FeCo/PMN-PT heterostructure [23], but the observed phenomenon was not consistent. Yang et al reported that only the extrinsic damping constant for FeCo/PMN-PT heterostructure can be reduced via substrate induced piezoelectric effect while the intrinsic damping constant was not by employing ferromagnetic resonance (FMR) technique [23]. Okada et al investigated thickness dependence of electric field modulated damping constant for CoFeB through FMR [42].…”

Section: Introductionmentioning

confidence: 97%

“…Aiming for this demand, electric voltage control of magnetism by designing ferromagnetic/ferroelectric (FM/FE) heterostructures via non-volatile polarization charge [7][8][9][10] or non-volatile strain derived from the underneath FE layer has been proved to be an efficient method in recent years. The ferroelectric crystals of PbZr 1−x Ti x O 3 (PZT) [16], Pb(Mg 1/3 Nb 2/3 ) 0.7 Ti 0.3 O 3 (PMN-PT) [17], and [Pb(Zn 1/3 Nb 2/3 )O 3 ] x -[PbTiO 3 ] 1−x (PZN-PT) [18] so on, are commonly adapted as a FE layer for their large piezoelectric property, and electric control of magnetization of the adjacent FM layer such as CoFeB [19][20][21][22], FeCo [23], Ni(Fe or Co) [24][25][26], and Co-based Heusler alloys [27][28][29][30][31][32][33][34] have been successfully demonstrated. The converse magnetoelectric (CME) coupling effect in FM/FE heterostructures contains the piezostrain-mediated effect [36][37][38], exchange bias-mediated effect [39,40], and charge-mediated effect [8,9].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Piezostrain modulation of magnetic damping in MBE-grown epitaxial Co₂FeAl/GaAs heterostructure

Li¹,

Bao²,

Wang³

et al. 2019

The electric voltage manipulated magnetic dynamic properties of Co 2 FeAl/GaAs heterostructure bonded on PbZr 1−x Ti x O 3 piezoelectric substrate were investigated using the time-resolved magneto-optical Kerr effect technique at room temperature. The butterfly-like response of precession frequency dependence on the applied electric field was observed with no external magnetic field applied, indicating efficient manipulation of precession frequency solely by piezostrain. The magnetic damping of Co 2 FeAl was observed to be enhanced (decreased) under the strengthened compressive (tensile) strain modulation. The observed efficient tuning of both precession frequency and extrinsic damping constant at low magnetic fields is attributed to piezostrain modulated magnetic anisotropy value and its inhomogeneous distribution. When the magnetic dynamics is governed by the external magnetic field at highfield regime, electric field tunability of precession frequency and damping constant becomes weaker and the intrinsic damping constant shows no modulation. The electric voltage tuning of magnetic damping and the associated physical mechanism presented in this work can help designing strain-mediated low-energy cost spintronic devices.