Multiple Magnetoionic Regimes in 
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"><mml:msub><mml:mi>Ta/Co</mml:mi><mml:mn>20</mml:mn></mml:msub><mml:msub><mml:mi>Fe</mml:mi><mml:mn>60</mml:mn></mml:msub><mml:msub><mml:mi mathvariant="normal">B</mml:mi><mml:mn>20</mml:mn></mml:msub><mml:mo>/</mml:mo><mml:msub><mml:mrow><mml:mi>Hf</mml:mi><mml:mi mathvariant="normal">O</mml:mi></mml:mrow><mml:mn>2</mml:mn></mml:msub></mml:math>

Pachat, Rohit; Ourdani, Djoudi; Jagt, Johannes W. van der; Syskaki, Maria‐Andromachi; Pietro, Adriano Di; Roussigné, Y.; Ono, Shimpei; Gabor, M. S.; Chérif, Mourad; Durin, Gianfranco; Langer, Juergen; Belmeguenai, M.; Ravelosona, D.; Diez, L. Herrera

doi:10.1103/physrevapplied.15.064055

Cited by 13 publications

(9 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This contribution to PMA is dominant, for example, in the archetypal Ta/CoFeB/MgO stacks and in Pt/Co/AlOx systems [ 23 ] and can be exploited to induce PMA though magneto‐ionic control of the oxidation level at the FM/oxide interface. [ 11,15 ] In the present case, neither positive (+4 V) nor negative gate voltages (−2.3, −2.5, and −3 V) produced an out‐of‐plane (OOP) signature in pMOKE for the as‐grown samples, as shown in Figure 1b. In contrast, in other liquid‐gated systems based on Pt/Co/HfO 2 and Ta/CoFeB/HfO 2 , the underoxidized as‐grown state shows PMA after application of similar negative voltages, due to the controlled oxidation of the FM/oxide interface.…”

Section: Resultsmentioning

confidence: 51%

“…In contrast, in other liquid-gated systems based on Pt/Co/HfO 2 and Ta/CoFeB/HfO 2 , the underoxidized as-grown state shows PMA after application of similar negative voltages, due to the controlled oxidation of the FM/ oxide interface. [11,15] It has been shown that a significant contribution to PMA can also arise from the heavy-metal (HM)/FM interface which depends on factors such as the 5d-3d hybridization of the heavy metal and ferromagnet's orbitals, interface intermixing and interface structure. [18,21,24] The contribution of the HM/FM interface to PMA has been found to be particularly important in W/CoFeB/MgO systems, including a significant dependence of PMA on the W crystalline phase.…”

Section: Resultsmentioning

confidence: 99%

“…Magnetoionic effects and functionalities that have been demonstrated include an electric field-induced spin reorientation transition (SRT) between PMA and in-plane anisotropy, [8] efficient domain wall traps, [9] control of saturation magnetization, [10] DMI [11] and the control of the spin accumulation direction for spin-orbit torques. [12] Recently, several works have focused on exploring the use of different types of ions [8,10,13] and FM/oxide interfaces [14] , as well as on modulating the degree of oxidation at FM/oxide interfaces [15,16] to control magnetic properties and gain insight into the magneto-ionic mechanism.…”

Section: Introductionmentioning

confidence: 99%

“…The impact of post‐growth annealing, which is vital to achieving robust magnetic properties in CoFeB‐based materials through crystallization, [ 17 ] on magneto‐ionics has only begun to spark an interest. In Ta/CoFeB/HfO 2 , post‐growth annealing has shown to critically reduce the speed of the magneto‐ionic response, [ 15 ] which has been attributed to a potentially lower ion mobility in crystallized systems compared to their amorphous counterpart. It is therefore of importance to characterize magneto‐ionics in annealed CoFeB systems to optimize both the magnetic properties of the films and their magneto‐ionic performance.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Magneto‐Ionics in Annealed W/CoFeB/HfO₂ Thin Films

Pachat

Ourdani

Syskaki

et al. 2022

Adv Materials Inter

Self Cite

View full text Add to dashboard Cite

The magneto‐ionic modulation of the Dzyaloshinskii–Moriya interaction (DMI) and the perpendicular magnetic anisotropy (PMA), in W/CoFeB/HfO2 stacks annealed at different temperatures and for varying annealing times, are presented in this work. A large modulation of PMA and DMI is observed in the systems annealed at 390 and 350 °C, whereas no response to voltage is observed in the as‐grown samples. A strong DMI is only observed in the samples annealed at 390 °C for 1 h, while PMA is present for all annealing times at temperatures of 390 and 350 °C. Magnetic properties including domain wall velocity improve drastically with increasing the annealing temperature and time, while the magneto‐ionic reversibility is increasingly compromised. The changes in PMA and DMI induced by the gate voltages in the samples annealed at 390 °C are permanent, while partial reversibility is only observed for the samples annealed at 350 °C for short times. This dependence of reversibility on post‐grown annealing has been associated to the influence of crystallization on ion mobility. These results show that a compromise between the enhancement of the magnetic properties and the magneto‐ionic performance could be needed in systems requiring annealing to develop PMA and DMI.

show abstract

Section: Resultsmentioning

confidence: 51%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Magneto‐Ionics in Annealed W/CoFeB/HfO₂ Thin Films

Pachat

Ourdani

Syskaki

et al. 2022

Adv Materials Inter

Self Cite

View full text Add to dashboard Cite

show abstract

“…In light of the emphasis on low-energy data storage, electrochemical gating control of interfacial magnetism has become a focal point. − This technique incorporates an electrolyte layer that functions as an ion reservoir. Upon the application of V G , the electric field drives the ion migration, contributing to the magnetism modulation through the formation of compounds. − Numerous studies highlight the significant role of ion intercalation in magnetism modulation. However, few investigations have explored its effects on grain dimensionality.…”

Section: Introductionmentioning

confidence: 99%

Electrical Control Grain Dimensionality with Multilevel Magnetic Anisotropy

Li,

Bhatti,

Teo

et al. 2024

ACS Nano

View full text Add to dashboard Cite

In alignment with the increasing demand for larger storage capacity and longer data retention, the electrical control of magnetic anisotropy has been a research focus in the realm of spintronics. Typically, magnetic anisotropy is determined by grain dimensionality, which is set during the fabrication of magnetic thin films. Despite the intrinsic correlation between magnetic anisotropy and grain dimensionality, there is a lack of experimental evidence for electrically controlling grain dimensionality, thereby impairing the efficiency of magnetic anisotropy modulation. Here, we demonstrate an electric field control of grain dimensionality and prove it as the active mechanism for tuning interfacial magnetism. The reduction in grain dimensionality is associated with a transition from ferromagnetic to superparamagnetic behavior. We achieve a nonvolatile and reversible modulation of the coercivity in both the ferromagnetic and superparamagnetic regimes. Subsequent electrical and elemental analysis confirms the variation in grain dimensionality upon the application of gate voltages, revealing a transition from a multidomain to a single-domain state, accompanied by a reduction in grain dimensionality. Furthermore, we exploit the influence of grain dimensionality on domain wall motion, extending its applicability to multilevel magnetic memory and synaptic devices. Our results provide a strategy for tuning interfacial magnetism through grain size engineering for advancements in high-performance spintronics.

show abstract

Magneto‐Ionic Control of Coercivity and Domain‐Wall Velocity in Co/Pd Multilayers by Electrochemical Hydrogen Loading

Bischoff,

Ehrler,

Engelhardt

et al. 2024

Adv Funct Materials

View full text Add to dashboard Cite

Magneto‐ionics, as the electrochemical reconfiguration of magnetic materials at low gating voltages, is a highly energy‐efficient alternative to control magnetism. For the fastest magneto‐ionic concept based on hydrogen, fundamental mechanisms are currently under debate, mainly because quantitative compositional information inside the magnetic materials upon gating is lacking. Using the electrochemical hydrogen loading of Co/Pd multilayers with perpendicular anisotropy, this study demonstrates that the hydrogen concentration inside the magnetic material determines its magnetic properties. Hydrogen concentrations up to a maximum of (0.24 ± 0.01) hydrogen atoms per metal atom can be set deterministically by voltage and are quantified via flow‐cell coulometry. With increasing hydrogen concentration, a continuous increase in coercivity of up to 15% and a decrease in magnetic domain‐wall velocity by an order of magnitude are observed using in situ MOKE microscopy. This enables the voltage‐controlled stop‐and‐go of domain walls. These magneto‐ionic effects can be explained by an increasing perpendicular anisotropy with increasing hydrogen content in Co/Pd multilayers, which is supported by theory. Importantly, the approach should be transferable to other ionic systems, such as lithium‐ or oxygen‐based ones, where it can uncover the yet hidden effects of ionic concentration on the magnetic properties and guide the design of functional magneto‐ionic devices.

show abstract

Multiple Magnetoionic Regimes in Ta/Co20Fe60B20/HfO2

Cited by 13 publications

References 47 publications

Magneto‐Ionics in Annealed W/CoFeB/HfO₂ Thin Films

Magneto‐Ionics in Annealed W/CoFeB/HfO₂ Thin Films

Electrical Control Grain Dimensionality with Multilevel Magnetic Anisotropy

Magneto‐Ionic Control of Coercivity and Domain‐Wall Velocity in Co/Pd Multilayers by Electrochemical Hydrogen Loading

Contact Info

Product

Resources

About

Multiple Magnetoionic Regimes in Ta/Co20Fe60B20/HfO2

Cited by 13 publications

References 47 publications

Magneto‐Ionics in Annealed W/CoFeB/HfO2 Thin Films

Magneto‐Ionics in Annealed W/CoFeB/HfO2 Thin Films

Electrical Control Grain Dimensionality with Multilevel Magnetic Anisotropy

Magneto‐Ionic Control of Coercivity and Domain‐Wall Velocity in Co/Pd Multilayers by Electrochemical Hydrogen Loading

Contact Info

Product

Resources

About

Magneto‐Ionics in Annealed W/CoFeB/HfO₂ Thin Films

Magneto‐Ionics in Annealed W/CoFeB/HfO₂ Thin Films