United States

We study the current-induced spin-orbit torque (SOT) switching and out-of-plane (OOP) effective field in a CuPt/CoPt heterostructure with interface oxidation. By introducing the oxidized copper at the interface, we found their switching abilities show remarkable improvement which is attributed to an unconventional OOP effective field. The OOP effective field is three times stronger than that without oxide treatment. Our observation identified the important role of the interface oxidation in the SOT process of CuPt/CoPt heterostructure.
The spin current can trigger a torque in ferromagnetic (FM) layer to electrically manipulate the magnetization. It is promise for an Magnetoresistive random-access memory (MRAM) device due to its endurance and speed [1-3]. To efficiently manipulate the magnetism in MRAM, the key point is to increase the spin accumulation in ferromagnetism (FM). In additiona, for traditional SOT devices, the external magnetic field is required to break the symmetry. Thus, the field-free switching has attracted attention.
We believe there could be a different path to enhance the field-free magnetization switching from material perspective. Previously, we studied the symmetry dependent field-free SOT switching in a CuPt/CoPt heterostructure [4]. The intrinsic broken mirror symmetry related SOT process is also reported in WTe2 [5]. The L11 CuPt deposited on SrTiO3 (111) substrate possesses a 3-fold symmetry, as shown in figure 1. The field-free switching emerges when the current is injected along the low symmetry axes ([1-10] and the other two equivalent axes).
In this work, we show the 3-fold symmetry unconventional out-of-plane torque is from the CuPt and it can be manipulated by the oxidation at the surface. Comparing to unoxidized sample, the oxidized sample approve a much larger switching ratio, since the large out-of-plane torque as the figure 2 shown. Regarding the oxidation degree of the copper is controllable by the time of oxidation treatment, thus a tuneable and efficient MRAM based on SOT induced magnetization switching is promised.&lt;br&gt;&lt;br&gt;
**References** [1] K. Garello et al., 2018 IEEE Symposium on VLSI Circuits., p.81-82 (2018).
[2] F. Oboril, R. Bishnoi, M. Ebrahimi and M. B. Tahoori, IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems., Vol. 34.3, p.367-380 (2015).
[3] G. Prenat et al., IEEE Transactions on Multi-Scale Computing Systems., Vol. 2.1, p.49-60 (2016).
[4] L. Liu et al., Nat. Nanotechnol., Vol. 16.3, p.277-282 (2021).
[5] MacNeill, D., Stiehl, G., Guimaraes, M. et al., Nature Phys., Vol. 13, p.300–305 (2017).
&lt;br&gt;&lt;br&gt;
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MMM 2022

Unconventional spin orbital torque enhanced magnetization switching by interface oxidation in CuPt/CoPt bilayer

We study the current-induced spin-orbit torque (SOT) switching and out-of-plane (OOP) effective field in a CuPt/CoPt heterostructure with interface oxidation. By introducing the oxidized copper at the interface, we found their switching abilities show remarkable improvement which is attributed to an unconventional OOP effective field. The OOP effective field is three times stronger than that without oxide treatment. Our observation identified the important role of the interface oxidation in the SOT process of CuPt/CoPt heterostructure.
The spin current can trigger a torque in ferromagnetic (FM) layer to electrically manipulate the magnetization. It is promise for an Magnetoresistive random-access memory (MRAM) device due to its endurance and speed [1-3]. To efficiently manipulate the magnetism in MRAM, the key point is to increase the spin accumulation in ferromagnetism (FM). In additiona, for traditional SOT devices, the external magnetic field is required to break the symmetry. Thus, the field-free switching has attracted attention.
We believe there could be a different path to enhance the field-free magnetization switching from material perspective. Previously, we studied the symmetry dependent field-free SOT switching in a CuPt/CoPt heterostructure [4]. The intrinsic broken mirror symmetry related SOT process is also reported in WTe2 [5]. The L11 CuPt deposited on SrTiO3 (111) substrate possesses a 3-fold symmetry, as shown in figure 1. The field-free switching emerges when the current is injected along the low symmetry axes ([1-10] and the other two equivalent axes).
In this work, we show the 3-fold symmetry unconventional out-of-plane torque is from the CuPt and it can be manipulated by the oxidation at the surface. Comparing to unoxidized sample, the oxidized sample approve a much larger switching ratio, since the large out-of-plane torque as the figure 2 shown. Regarding the oxidation degree of the copper is controllable by the time of oxidation treatment, thus a tuneable and efficient MRAM based on SOT induced magnetization switching is promised. 
**References** [1] K. Garello et al., 2018 IEEE Symposium on VLSI Circuits., p.81-82 (2018).
[2] F. Oboril, R. Bishnoi, M. Ebrahimi and M. B. Tahoori, IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems., Vol. 34.3, p.367-380 (2015).
[3] G. Prenat et al., IEEE Transactions on Multi-Scale Computing Systems., Vol. 2.1, p.49-60 (2016).
[4] L. Liu et al., Nat. Nanotechnol., Vol. 16.3, p.277-282 (2021).
[5] MacNeill, D., Stiehl, G., Guimaraes, M. et al., Nature Phys., Vol. 13, p.300–305 (2017).
 
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technical paper

#### Welcome to the 67th Annual Conference on Magnetism and Magnetic Materials, MMM 2022!

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The angle dependence of field-induced switching was investigated in magnetic tunnel junctions (MTJ) with in-plane magnetization and a pinned synthetic antiferromagnet reference layer. 60 nm x 90 nm elliptical nanopillars were patterned from a film stack of SiOx/Ta (5)/CoFeB (2.5)/MgO (1)/CoFeB (2.5)/Ru (0.85)/CoFe (2.5)/IrMn (8)/Ru (10), (units in nm).

The tunnel magnetoresistance (TMR) was measured while the external field was applied at an angle θ, varying from 0° to 180° relative to the major axis of the ellipse (MAE), as shown in the inset of Fig.1. The relative angle between the free layer magnetization and the MAE, φ, was calculated from the TMR using an empirical cosine relation. Single sharp switches are seen when the field was applied along the MAE, but even with small deviations, reversal occurred through an intermediate state. Fig.1 shows a representative hysteresis loop measured at θ = 20°.

To determine the magnetization direction at different points in the hysteresis loop, the energy landscape was modeled in terms of the effective shape anisotropy field, the external magnetic field, and the SAF stray field. Using an 8 Oe shape anisotropy effective field and the 26 Oe SAF stray field strength estimated from the loop shift, the magnetization direction as a function of the external field magnitude and direction was reconstructed. Fig.2 shows the energy diagrams of the device at the critical fields. Near 26 Oe the barrier between the two lowest energy states is low, consistent with the telegraphing observed in Fig. 1. Intentional misalignment of the SAF and shape anisotropy fields has potential for development of faster probabilistic spintronic devices [1]. 
**References** 1. H. Chen, et al., Appl. Phys. Lett. 120, 212401 (2022).
 
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Angle Dependent Switching in a Magnetic Tunnel Junction Containing a Synthetic Antiferromagnet

Spintronic phenomena to date have been established in ferromagnets (FMs) with collinear moments (e.g., Fe, Co, Y3Fe5O12), where all the moments can be aligned to give a large magnetization (M). In such collinear FMs, spin injection via spin Seebeck effect (SSE) is always along the out-of-plane direction (longitudinal SSE), but not in the in-plane direction (transverse SSE). In non-collinear antiferromagnets (AFs), there are magnetic moments in directions other than that along the net magnetization M, allowing general pure spin current phenomena to be established. In this work, we report the observation of vector SSE in non-collinear AF LuFeO3, where temperature gradients along both out-of-plane and in-plane direction can inject pure spin current and generate a voltage in the heavy metal via the inverse spin Hall effect. The results of longitudinal SSE (under an out-of-plane ▽zT) and the even larger transverse SSE (under an in-plane ▽yT) in LuFeO3/W are shown in the Figure. By using different metal overlayers (W, Pt and Cu/W), we show that the vector SSE is a spin current effect, where the thermovoltages are due to the magnetization from the canted moments in LuFeO3. We also ruled out the possibility of magnon Hall effect, spin Nernst effect and magnetic proximity effect in LuFeO3. One can exploit vector SSE as a vector magnetometer for detecting very small magnetization in all directions in non-collinear AF insulators. These novel results expand the realm of spintronics and enable new device architectures for AF spintronics and reveal general pure spin current phenomena beyond those in collinear magnets. 

This work was supported by US NSF DMREF (1729555 and 1949701), Taiwan MOST (109-2123-M-002-002), and US DOE(DE-SC0009390). 

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Observation of Vector Spin Seebeck Effect in a Non Collinear Antiferromagnet

Current-induced spin-orbit torque (SOT) is an efficient mechanism to manipulate the magnetization in magnetic materials [1]. In principle, the sizable SOT is believed to originate from the bulk spin Hall effect (SHE) and/or the interfacial spin Rashba- Edelstein effect (SREE) in heavy metals (HMs)-based magnetic heterostructures with strong spin-orbit coupling (SOC). Strikingly, recent reports suggest that the light metals (LMs) can also generate non-negligible SOTs and these sizable charge-to-spin conversions are attributed to the orbital angular momentum (OAM) induced orbital Hall effect (OHE) and/or orbital Rashba-Edelstein effect (OREE) [2]. The OAM dominating SOT generation has been experimentally explored in various LM-based systems such as Ti, Cr, and Cu-based magnetic heterostructures [3].
In this work, we prepare the Pt/Co/CuNx perpendicular magnetic heterostructures by reactive sputtering. By controlling the doping concentration, the overall SOT efficiency can be tuned from 6% to ~ 40%. The enhancement is attributed to combining the spin currents from Pt and the orbital currents generated by the nitrided Cu capping layer. Besides the conventional SOT characterizations, we further demonstrate the neuromorphic switching and show that the orbital currents can effectively manipulate the perpendicular magnetization. These results provide valuable information for building energy-efficient spin-orbitronic devices utilizing both the spin and the orbital effects [4]. 
**References** [1] L. Liu et al., Science 336, 555 (2012).
[2] D. Lee et al., Nature Communications 12, 6710 (2021).
[3] S. Lee et al., Communications Physics 4, 234 (2021).
[4] T.-Y. Chen et al., Physical Review Applied 17, 064005 (2022). 
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Spin orbit torque switching mediated by orbital currents from CuNx

We present spin transport studies on a low-field, room-temperature magnetoelectric multiferroic polycrystalline Sr3Co2Fe24O41|Pt heterostructure wherein a highly tunable transverse conical magnetic phase is responsible for static and dynamic magnetoelectric coupling [1, 2]. We measured angular dependence of spin Hall magnetoresistance (SMR) at constant magnetic fields (H) in the range of 50 to 100 kOe. Application of field below the critical value (Hc1 ≈ 2.5 kOe), yielded negative SMR and the H-evolution of normalized SMR (△R/R0 × 100 %) exhibited a negative gradient. Further, an increase in the H resulted in the positive slope of △R/R0 × 100 % Vs. H and later at higher H around 14 kOe, a crossover from negative to positive SMR was observed. We employed a simple model for estimating the equilibrium magnetic configuration and computed the SMR modulation at various values of H. We argue that the tilting of the cone is dominant and in turn responsible for the observed nature of SMR below 2.5 kOe (Fig.1) while, the closing of the cone-angle is pronounced at higher fields causing a reversal in sign of the SMR from negative to positive (Fig.2). Importantly, SMR experiments revealed that a change in the helicity with a reversal of the magnetic field has no influence on the observed SMR. Longitudinal spin Seebeck effect (LSSE) signal was measured to be ≈ 500 nV at 280 K, under application of thermal gradient, △T = 23 K and field, 60 kOe. The observed LSSE signal, originating from pure magnon spin current, showed a similar H-dependent behavior as that of the magnetization of Sr3Co2Fe24O41. Our detailed spin transport studies on polycrystalline Sr3Co2Fe24O41|Pt heterostructure demonstrate high tunability of the amplitude and the sign of the SMR, highlighting its potential for novel spintronic devices such as SMR-based spin valves [3] and voltage-controlled spin transport devices. 
**References** [1] Y. Kitagawa, Y. Hiraoka, T. Honda, Nat. Mater., Vol. 9, p. 797 (2010)
[2] H. Ueda, Y. Tanaka, Y. Wakabayash, Phys. Rev. B, Vol. 100, p. 094444 (2019)
[3] Y.-T. Chen, S. Takahashi, H. Nakayama, Phys. Rev. B, Vol. 87, p. 144411 (2013) 
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Highly tunable spin Hall magnetoresistance in room temperature magnetoelectric multiferroic, Sr3Co2Fe24O41|Pt hybrids

Magnetic skyrmions are a topic of extensive research due to their unique magnetic properties and spintronic applications. The primary way to achieve skyrmion dynamics is through electric currents, via STT effects [1]. The current can displace a skyrmion, but it usually also imparts an unwanted perpendicular velocity component known as skyrmion Hall effect (SkHE) [2]. Finding a way to counter SkHE has recently become a topic of intense research [3, 4]. In this work, we show that geometric variations can be used to achieve confinement of skyrmions in both static and dynamic cases. We have analyzed skyrmions in FeGe structures using finite-element and finite-difference micromagnetic simulations. For the static case, we find that by locally lowering the film thickness in dot-shaped regions (Fig. 1), skyrmions can be "captured" at geometrically defined sites [5]. In this way, skyrmions can be stabilized at positions such as square lattices, which otherwise do not occur in usual non-centrosymmetric ferromagnets. For the dynamic case, we consider a novel "H"-shaped racetrack geometry (Fig. 2). In the presence of a current along the track length, the simulations confirm that the barrier counters the SkHE while allowing skyrmion propagation along the geometrically defined path. We further analyze its trajectories and velocities as a function of current density and compare the numerical results with Thiele's equation [6]. Our study confirms that the numerically obtained skyrmion velocities are in accordance with Thiele's equation. In summary, we present a way to confine three-dimensional skyrmions by exploiting the dependence of skyrmion energy on the film thickness. This can prove valuable in the study of exotic configurations such as a rectangular skyrmion lattice. It may also prove relevant to countering the SkHE in skyrmion-based racetrack devices. This work was financially supported by initiative of excellence IDEX-Unistra (ANR-10-IDEX-0002-02) and the EPSRC Program grant on Skyrmionics (EP/N032128/1). 
**References** 
[1] J. Sampaio et al., Nat. Nanotechnol., 8, 839 (2013).
[2] I. Purnama et al., Sci. Rep., 5, 10620 (2015).
[3] W. Legrand et al., Nat. Mater., 19, 34 (2020).
[4] B. Göbel et al., Phys. Rev. B, 99, 020405 (2019).
[5] S. A. Pathak & R. Hertel, Magnetochemistry, 7, 26 (2021).
[6] J. Iwasaki et al., Nat. Nanotechnol., 8, 742 (2013). 

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Fig. 1 Geometrically constrained skyrmions in FeGe platelets with circular pockets. 

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Fig. 2 Snapshots of the skyrmion dynamics in an H-shaped racetrack geometry.

Three dimensional Skyrmion Confinement Through Thickness Modulation

The ability to manipulate the topological spin textures, such as magnetic skyrmions, is one of the crucial requirements in advance spintronics research. Recently, attempts have been made to understand the mechanism of Domain wall (DW) pair to skyrmion conversion in a specially designed nanotrack which may be useful in memory and logic operation [1,2]. Here, using micromagnetic simulation, we investigate the role of geometry in controlling the DW to skyrmion conversion in a three-channel narrow nanotrack adjoined to a wide nanotrack. Dimension of the nanotrack is as follows; length - 800 nm, thickness - 1 nm, width of narrow nanochannel - 20 nm, width of wider nanochannel - 200 nm, with spacing between the three narrow channels (lower -1, middle - 2, and upper - 3) varied symmetrically and asymmetrically from 10 - 30 nm in step of 10 nm. The simulations are performed using a python interfaced OOMMF known as Ubermag, where a Zhang-Li torque evolver in the Landau-Lifshitz-Gilbert equation is incorporated to understand the magnetization dynamics under the influence of spin current [3]. In figure 1, by keeping the separation between narrow channels 1 and 2 as well as 2 and 3 fixed as 10 nm, Gilbert damping α = 0.3 and non-adiabatic torque parameters β = 0.3, conversion of DWs to two skyrmions are shown [4]. Interestingly, we note that while the steady state velocity for both the skyrmions are same, the time scale involved in DW to skyrmion for individual skyrmion varies resulting in difference in the x-position. By increasing the separation between channel 2 and 3 to 30 nm and keeping all other parameters fixed, formation of a skyrmion and a meron is observed in figure 2. We envision that such difference in the observation of topological spin texture by changing the separation between the narrow nanochannels will be useful for implementing futuristic skyrmion-based logic gate devices. 

**References** 
[1] A. Fert, V. Cross, J. Sampaio Nature Nanotech., Vol. 8, p. 152, (2013). 
[2] Y. Zhou, M. Ezawa, Nat. Commun., Vol. 5, p. 4652, (2014). 
[3] M. Beg, M. Lang, H. Fangohr., IEEE Trans. Magn. Vol. 58, p. 1-5 (2021) 
[4] P. Hari Prasanth, Syamlal S K, B. Priyanka, J. Sinha, Manuscript under preparation. 

![](https://s3.eu-west-1.amazonaws.com/underline.prod/uploads/markdown_image/1/image/d1d0c5f3d1bfa99da4e93dfe7637c1cd.png) 
Fig 1: Snapshot of DW to skyrmion conversion from the three symmetrically separated narrow nano-channels for α = β = 0.3 and separation - 10 nm. 

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Fig 2: From asymmetrically separated narrow nano-channels (separation between 1 and 2 - 10 nm and between 2 and 3 - 30 nm) and for α = β = 0.3 conversion of DWs into a skyrmion and a meron.

Controlled skyrmion creation from a Domain wall pair for logic gate applications

The share of electric vehicles (EVs) on the road has seen a dramatic upward trend in the last decade as maximum range per charge has increased and the necessary infrastructure has grown to increase competitiveness with conventional gasoline-powered vehicles. However, maximal efficiency, achieved by minimizing the losses experienced by the motor stator and rotor, is limited by a tradeoff between low coercivity and high mechanical strength, which is necessary to withstand the significant torques experienced during operation [1–3]. Radiofrequency (RF) transverse induction annealing (T-IA) is suggested as a novel pathway for imposing a continuous spatial variation in microstructure of bulk crystalline soft magnetic alloys [4,5]. Via local control of grain size, magnetic and mechanical properties may be separately prioritized as functions of position, enabling fabrication of optimized motor laminations with reduced losses while still possessing requisite mechanical strength. Here we demonstrate through FEA modeling the dependence of achievable temperature profile on lamination and coil geometry, and we confirm feasibility of spatially optimized microstructure through experiments. We find that certain combinations of coil/lamination geometry may allow for simultaneous stamping of spatially optimized laminations, due to enhanced heating and higher temperature distributions in the region of the laminations where the magnetic flux density is greatest. We also present a basic feasibility modeling study examining performance of a motor containing motor laminations with radial variation in coercivity to motivate future work in this area. 
**References:** [1] T. Sourmail, Prog. Mater. Sci., Vol 50, p.816–880 (2005) 
[2] P. Ramesh and N.C. Lenin, IEEE Trans. Magn., Vol. 55, 0900121 (2019) 
[3] T. Sourmail, Scr. Mater., Vol. 51, p.589–591 (2004) 
[4] A. Talaat, D.W. Greve, and S. Tan, Adv. Energy Mater., Vol. 2022, 2200208 (2022) 
[5] A. Talaat, D.W. Greve, and M. V. Suraj, J. Alloys Compd., Vol. 854, 156480 (2021) 

![](https://s3.eu-west-1.amazonaws.com/underline.prod/uploads/markdown_image/1/image/22a24c959fc2dde91f2bd9577aee7567.png) 
Fig. 1: (a) Schematic of temperature/property profile achievable with a cylindrical coil as simulated in COMSOL Multiphysics (b) Experimental temperature profile observed with a cylindrical coil and square Hiperco lamination.

Fabrication and Feasibility Study of Motor Laminations with Radially Varying Coercivity via Transverse Induction Annealing

Graphene has unique electronic properties which make it a promising material for next-generation electronics. It has high electron mobility at room temperature and a long spin-diffusion length. The latter is due to its weak intrinsic hyperfine interactions and small spin-orbit coupling. Therefore manipulating spins directly in a layer of pristine graphene is not easy. However, this can be overcome by an induced proximity effect using an exchange-coupled interface between the graphene and a ferromagnetic layer. Several studies predicted that the conduction band of graphene will spin split at the interface with a ferromagnetic substrate [1-4]. 

We report the magnitude of the induced magnetic moment in graphene as a result of the proximity effect in the vicinity of a Ni layer using polarised neutron reflectivity (PNR) and X-ray magnetic circular dichroism (XMCD). The Ni film was grown by sputtering upon which the graphene was grown by chemical vapour deposition. The growth parameters were tuned to produce epitaxial and rotated graphene domains (Fig. 1). The XMCD results at the C K-edge confirm the presence of magnetic polarisation in rotated graphene. Intensive quantitative analysis of the PNR fits, ascertained based on Bayesian analysis, indicate that at 10 K 0.53 and 0.38 μB/C atom is induced in rotated and epitaxial graphene grown on Ni(111), respectively. These values are three times higher than those predicted in other studies [4,5]. Two possible mechanisms were elaborated for the observed induced magnetic moment [4,6,7]. To clarify the origin of the measured moment, further PNR measurements were carried out on graphene grown on a non-magnetic substrate (Ni9Mo1) [8]. 

We will present the different models used to fit the data and discuss the challenges of fitting the PNR of a 2D material which is within the resolution limit of the technique. We will also show the results of other techniques used to characterise the samples. 
**References:** [1] H. Haugen et al., Phys. Rev. B 77, 115406 (2008). 
[2] Q. Zhang et al., Appl. Phys. Lett. 98, 032106 (2011). 
[3] H.X. Yang et al., Phys. Rev. Lett. 110, 046603 (2013). 
[4] M. Weser, Y. Rehder et al., Appl. Phys. Lett. 96, 012504 (2010). 
[5] H. -Ch. Mertins et al., Phys. Rev. B 98, 064408 (2018). 
[6] V. Karpan, P. Khomyakov et al., Phys. Rev. B 78, 195419 (2008). 
[7] F. Ma’Mari, T. Moorsom et al., Nature 524, 69 (2015). 
[8] R. O. M. Aboljadayel et al., arXiv:2101.09946v2 (2022). 

![](https://s3.eu-west-1.amazonaws.com/underline.prod/uploads/markdown_image/1/image/26e01e1a2ae11689057c5c16ffd68ca2.png) 
SEM images at 1 kV showing the graphene domains for (a) epitaxial graphene/Ni and (b) rotated graphene/Ni and (c) The LEED diffraction pattern of epitaxial graphene on a Ni(111) substrate at 300 eV. The red circle in (b) highlights a single graphene domain with a diameter of ∼ 0.25 μm.

Determining Quantitatively the Induced Magnetic Moment in Graphene by Polarised Neutron Reflectivity and X ray Magnetic Circular Dichroism

Low dimensional molecular magnets are considered to be one of the best materials for cryogenic magnetocaloric effect (MCE) [1,2]. The magnitudes of magnetic entropy change for the most efficient molecular materials are comparable to that of the famous gadolinium gallium garnet (Gd3Ga5O12). Although much research effort is focused on searching high efficient compounds for conventional MCE, a new type of magnetocaloric effect, namely rotating magnetocaloric effect (RMCE), has been introduced. In RMCE, the applied magnetic field is constant and the aligned material (often in single crystal form) with significant magnetic anisotropy is being rotated. Cooling with rotation has several advantages compared to the conventional MCE cooling setups: high efficiency (high frequency cooling cycles), simple construction and low power consumption ( possibility of using permanent magnets). In our research we have investigated the RMCE in 2D compounds (based on MnII-NbIV [3] and CuII-WV [4] ions) and clusters (based on TbIII and DyIII [5]). We have noticed that the inverse magnetocaloric effect can be used to enhance RMCE (in our case up to 51 % for the 2D compounds). In the case of the Tb cluster, with large uniaxial anisotropy, the magnetic entropy change for conventional and rotating MCE is comparable, showing significant values (Î”Smax â‰ˆ 4 J K-1 kg-1) at 2.0 K in low field (Î¼0H â‰ˆ 1.2 T), which can be achieved with permanent magnets.

Rotating Magnetocaloric Effect in Low Dimensional Molecular Compounds

Magnetic refrigeration is a sustainable, energy-efficient alternative to the conventional vapor-compression cooling technology. A key challenge in manufacturing magnetocaloric devices is that lack of fabrication methods for shaping the brittle caloric alloys into thin-walled channeled regenerator structures with optimized heat transfer properties, and gradient transformation temperature, while preserving the functional response of the materials system, Fig 1.1 To this end, we have recently developed a novel extrusion-based additive manufacturing (AM) method to 3D print spatially designed porous magnetocaloric structures with channel dimensions in the range 150-800 Âµm, Fig 2.1 Building on this proof-of-concept demonstration, research efforts pertaining to AM process development using three precursor magnetocaloric powders will be presented - (1) La0.6Ca0.4MnO3 nanoparticles (dia~10 nm) prepared by Pechiniuidelines for minimizing porosity and lack-of-fusion defects in the 3D printed magnetocaloric parts.

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Unconventional spin orbital torque enhanced magnetization switching by interface oxidation in CuPt/CoPt bilayer

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