Recently, there has been a growing interest in developing and using magneto-optical polymer nanocomposites (MO-PNCs) as efficient Faraday rotators [1,2]. A common
strategy to improve the Verdet constant, V, of MO-PNCs is by increasing the nanoparticle (NP) loading [3]. However, since the absorption coefficient, α, also increases with the loading,
the figure-of-merit, FOM = V/α, remains unchanged. In this work, we first showed that the FOM in Fe3O4-based MO-PNCs is independent of NP loading in the absence of aggregation and
decreases when NPs aggregate. Secondly, we demonstrated that the FOM is strongly sensitive to the NP size and composition via doping with terbium ions (Tb3+). In the loading study, we
used a polymerizable ligand to fabricate poly (methyl methacrylate) films containing 8 nm Fe3O4 NPs with high optical quality [4]. When the NP loading was increased from 3.5 to 12.8
wt%, the Verdet constant of the films improved from 4500 to 13500 °/Tm whereas the FOM remained constant at 2.9 °/T. This result confirms our expectation that increasing the loading
does not enhance the overall MO performance. When the NP diameter was increased from 8 to 17 nm, we observed a 7-fold enhancement in the FOM from 2.9 to 23.1 °/T (Fig. 1) which
can be attributed to the NPs reaching the critical size (~20 nm) at which their magnetic domains become stable against thermal fluctuations [5]. For larger sizes, however, the Verdet
constants saturated while FOMs declined due to increased aggregation. The FOM was further improved to ~70 °/T by doping with the highly MO-active Tb3+ ions (Fig. 2) [6]. The drop in
FOM at high Tb3+ doping is likely due to the increased lattice distortions and failure to incorporate the dopants inside the NPs [7]. At the optimal doping and size, the Verdet constant of
4wt% loaded MO-PNC film is 5.6×105 °/Tm which is among the highest reported in the literature, especially for moderately loaded films [1]. The MO-PNCs reported in this work are
promising candidates for compact room-temperature optical magnetometers that can be used for sensing and medical imaging. 


**References:** 

[1] K. Carothers et al., Chem. Mater., vol. 34, p.2531–2544, (2022) 
[2] N. Pavlopoulos et al., J. Mater. Chem. C, vol. 8, p.5417–5425, (2020) 
[3] K. Carothers et al., Chem. Mater., vol. 33, p.5010–5020, (2021) 
[4] Y. Jin et al., J. Mater. Chem. C, vol. 4, p.3654–3660, (2016) 
[5] A. Muxworthy et al., J. R. Soc. Interface, vol. 6, p.1207, (2009) 
[6] K. Miyamoto et al., J. Am. Chem. Soc., vol. 131, p.6328–6329, (2009) 
[7] K. Rice et al., Appl. Phys. Lett., vol. 106, p.062409, (2015) 

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Magneto Optical Figure

Nanocomposites (NCs) are multicomponent materials in which a nanoscale reinforcement is added to a host matrix to combine their different properties. In this work, we
investigate the magneto-optical (MO) properties of an NC made of Soda Lime Glass (SLG), which is a transparent, nonmagnetic, and cheap matrix doped by nanostructures of Cobalt (Co),
a magnetic material. Among various MO effects, the Faraday Effect (FE) describes the polarization modifications of a linearly polarized light when it travels through a magnetized
material. This effect manifests itself as two angles (θ, ε) depicting the polarization rotation and the ellipticity of the emerging light. The Co-SLG NC was formed in two successive steps: a
Co layer was deposited on the glass surface, then diffused into the glass using the thermal poling technique [1]. The FE effect was measured at different wavelengths (λ), while the applied
magnetic field (H) varied between -800 and +800 mT. Such FE-H curves describe the magnetic properties of the material under consideration. “Fig. 1-2” shows the θ-H curves measured at
λ=700 nm, for the Co layer “Fig. 1”, as well as for Co-SLG NC “Fig. 2”. The Co layer exhibits a hysteresis loop, which is characteristic of ferromagnetic materials (FM). After thermal
poling, the curve is linear, which indicates that the diffusion of the Co layer within the glass matrix changes drastically its magnetic behavior, most likely due to the oxidation of the Co ions
since the SLG matrix is oxygen-rich. “Fig. 3” presents the spectral behavior of this FE effect for the cobalt layer (saturation value of θ as a function of λ) and the NC (slope of θ-H curve as
a function of λ). Two main bands are observed in the case of the NC, centered at around 700 nm and 1400 nm, whereas no bands are observed for the Co layer. These two bands are
assigned to MO dipolar transitions of Co2+ ions in the tetrahedral sites of the Co3O4 structure [2]. If this NC is irradiated with a continuous wave laser, Co3O4 can be transformed
reversibly to CoO [1]. Since Co3O4 and CoO have different magnetic and MO behaviors, such NCs may lead to a promising photomagnetic feature that can be used in data storage
applications or optical MO switching. 

**References:** 

[1] R. Faraj, F. Goutaland, N. Ollier, Physica Status Solidi B., Vol. 257, p.2000155 (2020) 
[2] W. F. J. Fontijn, P. J. van der Zaag, L. F. Feiner, R. Metselaar, M. A. C. Devillers, Journal of Applied Physics, Vol. 85, p.5100-5105 (1999) 

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Magneto Optical Properties of Cobalt

Soft actuators are required to deform, fold, or unfold in order to interact with their surroundings.[1] One strategy to achieve the movement of mechanically soft systems is
the use of magnetic fields for untethered actuation. Flexible magnetic composites have been demonstrated as functional grippers, rollers, and walkers upon applied external magnetic fields.
[2] Being controlled with electromagnetic coils, magnetic actuators can profit from high-speed actuation to quickly respond to their environment.[3]
The development of an appropriate sensory tracking system for soft actuators is a research topic with open challenges. Light, conformal, and mechanically imperceptible sensing systems
are to be developed to be compatible with soft actuators. In this work, we present flexible magnetosensitive electronic skin which relies on thin-film magnetic field sensors to enable
onboard folding control of origami-like soft actuators. The flexible electronic skin consists of thin film giant magnetoresistive GMR and Hall effect sensors that are used to measure the
magnetization state of the actuator, the applied magnetic fields, and the completeness of the bending process. The resulting intelligent material is mechanically designed to fold even when
the flexible magnetic skin is attached to the soft actuator.[4]
The magnetic origami actuators are made of thin DiAPLEX foils, a shape memory polymer, with embedded NdFeB particles. Such composite can be used to achieve magnetically induced
motion using magnetic fields and a directed light source to increase locally the temperature. We experimentally found the best thickness (60 μm) and concentration (40 NdFeB wt%)
parameters to achieve magnetic folds.[4]
The integration of magnetic soft actuators with e-skins allowed the self-guided assembly of the origami foils. We showed two case studies showing that this approach is useful for
assembling boxes and boat-like origami shapes. This integration process was monitored, followed, and controlled by the output of the laminated sensors. [4] 

**References:** 

[1] A. Miriyev, K. Stack, H. Lipson, et al. Nat. Commun., Vol. 8, p.596 (2017) 
[2] S. Wu, W. Hu, Q. Ze, et al. Multifunct. Mater. Vol. 3, p.042003 (2020) 
[3] X. Wang, G. Mao, G. Jin, et al. Commun. Matter. Vol. 1, p.67 (2020) 
[4] M. Ha, G.S. Cañón Bermúdez, J.A.-C- Liu, et al. Adv. Mater. Vol. 33, p.2008751 (2021)

Magnetically Sensitive Electronic Skins for Supervised Folding of Origami Actuators

Hard-magnetic soft materials has a lot of application scenarios in the field of soft robots and flexible sensors. But, due to the coupling of magnetization process and
manufacturing process, the functions of these devices can not be changed. Therefore, the technique of repeatedly program magnetic anisotropy on magnetic elastomer is of great
significance for changing the functions of magnetic soft robot and sensor. This paper presented a reprogrammable mangetic elastomer based on
Liquid-metal/NdFeB/Silicone composites. The NdFeB particles wrapped in gallium can be re-orientated by thermal-ssisted magnetic programming(Figs.1a-1c). Thus, the magnetization
profile can be reconfigurated on the elastomer(Fig.1d).X-ray diffraction (XRD) analysis shows the phase composition of gallium, Silicone and Nd2Fe14B (Fig.2a). The elstomer's magnetic
properties are tested by the comprehensive physical property measurement system (PPMS). The moment-temperature (M-T) curve shows the material's moment jumps at 303 K（the melt
point of gallium)(Fig.2b). And the moment-magnetic field (M-H) curves indicate that the elastomer exhibit hard and soft magnetic properties respectively (Fig.2c), when the temperatureis
lower (293 K) or higher (313 K) than the phase-transition temperature of gallium. A hexagon-shape robot was manufactured and then programmed to two modals of grasping and walking
respectively(Figs.2d and 2e).The experimental results verify the reprogrammability of the proposed composite elastomer. The elastomer is expected to be used to manufacture multi-modal
magnetic soft robot. 

**References:** 

1. H. Chung, A. M. Parsons, L. Zheng.Magnetically Controlled Soft Robotics Utilizing Elastomers and Gels in Actuation: A Review. Advanced Intelligent Systems, 2020,
2000186. 
2. Y. Yan, Z. Hu, Z. Yang, etc. Soft magnetic skin for super-resolution tactile sensing with force self-decoupling. Science Robotics, 2021, 6, eabc8801. 
3. L. Cao, D. Yu, Z. Xia, etc. Ferromagnetic Liquid Metal Plasticine with Transformed Shape and Reconfigurable Polarity.Advanced Materials, 2020, 2000827. 
4. R. Zhao, H. Dai, H. Yao. Liquid-Metal Magnetic Soft Robot with Reprogrammable Magnetization and Stiffness.IEEE Robotics Automation and Letters, 2022, 7(2): 4535-4541. 

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Reprogrammable Liquid metal/NdFeB/Silicone Composite Magnetic Elastomer

Soft magnetic elastomers (ME) are a class of smart materials consisting of magnetic particles dispersed within soft elastomer networks. Their excellent magnetic and
mechanical properties enable fast, untethered and reversible responses to external magnetic induction1. Magnetic field sensors have rather broad applicability in many biomedical
applications such as biological activity monitoring or medical devices navigation. Fiber-optic magnetic field sensors are promising alternatives to their electrical counterparts due to their
small size, low cost, no field-induced heating, intrinsic material safety and immunity to electromagnetic (EM) interference.2 Nevertheless, their development is largely limited by the low
sensitivity and reliability due to poor integration of magnetic materials with the optical fiber, and the complexity of the sensor design.
In this work, we proposed a compact design for a fiber-optic magnetic sensor based on highly responsive ME composites, which enables real-time measurement of small changes in
magnetic fields using interferometric interrogation scheme. Dip-coating method was introduced to directly deposit uniform ME composite films on the end of a single mode fiber and create
a interferometric structure for sensing of mechanical deformations induced by external magnetic field (Fig1 and 2). ME composites of different compositions and magnetic sensors with
various coating structures were developed and further optimized. A fiber-optic interferometric sensing system was established for magnetic actuation and sensing performance evaluation.
The proposed sensor exhibited excellent sensing performance enabling measurement of magnetic fields in millitesla level. These highly sensitive, miniature sensors are cost-effective,
simple in design, immune to EM interference and are well-suited to a wide range of biomedical applications. Further studies will entail simultaneous measurement of magnetic field and
gradient. 
**References:** 

1. Bira, N., Dhagat, P. & Davidson, J. R. Front. Robot. AI 7, 1–9 (2020). 
2. Peng, J. et al. Sensors 19, 2860 (2019). 

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Soft Magnetic Elastomer Composites Enabling Magnetic Actuation and Field Sensing Based on Fiber Optic Interferometry

Hybrid magnonic-electric computing architectures are promising for ultra-low power data processing [1,2]. To realize these computing systems, scalable magnetoelectric
transducers are required that efficiently convert signals between the electric and magnetic domain. Several transducer types have been proposed of which voltage-based concepts are
expected to have the best scaling characteristics [3]. A promising voltage-based transducer type consists of a piezoelectric/magnetostrictive bilayer [4]. When a voltage is applied to this
transducer, dynamic strain is induced in the bilayer via the piezoelectric effect. This dynamic strain then interacts with the magnetization via the magnetostrictive effect and a coupling
between the electric and magnetic domain is obtained. Although this transducer type is very promising, its fundamental understanding as well as energy efficiency estimates are currently
lacking.
In this work, we develop a theoretical model of the displacement and magnetization dynamics in a resonator consisting of a piezoelectric/magnetostrictive bilayer. The model considers
both elastic as well as magnetic resonances and captures the magnetoelastic effect via an effective stiffness. Via this approach, both the elastic and magnetic power flow inside the device
can be determined. A comprehensive analysis was conducted of the dimensional as well as material parameter influence on the elastic and magnetic power dissipation (see Fig. 1).
Furthermore, the power calculation also results in magnetic transducer efficiency estimates. The results show that magnetic excitation efficiencies up to 90% can be achieved for nanometer
thick magnetostrictive layers (Fig. 2). Finally, a figure of merit is determined which allows to select the optimal piezoelectric-magnetostrictive material combination. 

**References:** 

1. A. Khitun and K. L. Wang, J. Appl. Phys. 110, 034306 (2011). 
2. B. Dieny, I. L. Prejbeanu, K. Garello, P. Gambardella, P. Freitas, R. Lehndorff, W. Raberg, U. Ebels, S. O. Demokritov, J. Akerman, et al., Nature Electron, 3 (2020). 
3. F. Vanderveken, V. Tyberkevych, G. Talmelli, B. Soree, F. Ciubotaru, and C. Adelmann, Sci. Rep. 12, 3796 (2022). 
4. A. Khitun, D. E. Nikonov, and K. L. Wang, J. Appl. Phys. 106, 123909 (2009). 

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Power transfer in magnetoelectric resonators

Metamagnetic Heusler compounds display a first order structural transformation associated with large changes of magnetization and/or magnetic order. Their properties can
be tuned by suitable changes in composition making them a versatile class of multifunctional materials, thanks to the strong interplay between thermal, mechanical and magnetic degrees of
freedom [1]. In addition, their hierarchically interrelated twin-with-twin microstructure, in the low temperature martensitic phase, and the strong spin-lattice coupling allow to control their
magnetic and multifunctional properties from the atomic to the micro-scale by tuning growth conditions and applying external fields [2, 3].
In my talk I will report on our recent results on nano/microscale materials obtained by different fabrication methods (e.g. epitaxial thin films, patterned and free-standing structures) [3-6].
Thin films and micro/nanostructures are of particular interest not only for the realization of new-concept devices, but also for providing insights into the magnetostructural coupling at the
different length scales. The talk will focus on microstructure engineering and microstructure related effects on the martensitic transformation, also in view of the possible exploitation of
this class of materials in energy related and smart applications.
In particular, by an accurate magnetic and structural investigation at different length-scales, I will demonstrate how growth temperature and simple post-growth treatments, i.e. postannealing
at low T, magnetic field cooling and mechanical stress, are suitable to manipulate the twin variant configuration in epitaxial thin films. X-type variants with out-of-plane
magnetic easy axis or Y-type variants with in-plane magnetic easy-axis can be selected, as well as their geometrical distribution, in films with mixed X/Y-type microstructure [3].
Taking advantage from the possibility to manipulate microstructure we have studied the role of specific martensitic configurations on the martensitic transition path. By advanced magnetic
force microscopy imaging in a wide temperature (260–350 K) and magnetic field range (up to 14 T) we have directly observed the nucleation and the self-accommodation of the martensitic
twinning configurations under zero-field, isofield and isothermal conditions. We have found that between the two possible twinning configurations, the Y-type, which nucleates first, shows
a significantly smaller thermal hysteresis as well as a sharper phase transition with respect to X-type microstructure, for all the three investigated conditions [4].
The effects of lateral size, shape and geometry on the properties of patterned epitaxially grown Ni-Mn-Ga films will also be discussed. In particular, I will present the characterization of
arrays of microstructures, obtained by means of different lithographic techniques, with lateral sizes down to 200 nm range and having different shapes and orientations with respect to the
substrate edges [5].
The last part of my talk will be devoted to free-standing nanostructures in view of their possible exploitation as micro/nano actuators exploiting microstructure-controlled actuation
mechanisms by the combined application of temperature and magnetic field [6]. 

**References:** 

[1] M. Acet, L. Mañosa, A. Planes, Handbook of Magnetic Materials (Ed: K. H. J. Buschow), Elsevier, Amsterdam 2011, pp. 231–289 
[2] P. Ranzieri et al., Adv. Mater. 2015, vol. 27, p. 4760 
[3] M. Takhsha Ghahfarokhi et al. Acta Mater. vol. 187, p. 135–145 (2020) 
[4] M. Takhsha Ghahfarokhi et al. Acta Mater. vol. 23, 117356 (2021) 
[5] M. Takhsha Ghahfarokhi, et al. Appl. Mater. Today vol. 23, p. 101058 (2021). 
[6] M. Campanini et al., Small, vol. 14, p. 1803027 (2018) 

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NiMn based Heusler thin films: an amazing class of ferromagnetic shape memory alloys

Magnetic elastomers can mechanically deform under a magnetic field. Hard magnetic elastomers can perform more complex motions, but soft magnetic elastomers have a greater magnetoaction. 3D printing, such as Fused Deposition Modeling (FDM), can enhance the magnetoactive properties of magnetic elastomers by creating anisotropy. 3D printing filaments are the stock material for FDM. Recent work has shown that magnetic annealing of magnetic filaments during extrusion creates greater magnetoaction in the filaments. This research studies whether this enhanced performance from magnetically annealed filaments remains once they are extruded through the 3D printing nozzle. The composite samples were made of polyurethane and varying amounts of soft and hard magnetic particulate (carbonyl iron (Fe) and strontium ferrite (SrF)). The composites were extruded into 1.75 mm diameter filaments. Magnetically annealed filaments traveled through a uniform axial magnetic field. Final samples were extruded through a 0.8 mm FDM nozzle into extrudates. The magnetoactive properties were measured by a custom setup, whereby extrudates were hung between electromagnets. Images of samples were captured, overlaid, and analyzed at seven field strengths. The enhanced magnetoactive performance of magnetically annealed filaments was present in the final extrudates, indicating that the magnetic annealing effects were preserved. The higher performance magnetic annealing effects were (1) magnetoaction at lower applied fields for the Fe-containing samples and (2) non-zero magnetoaction in the highest SrF samples. Quantitatively, the least magnetoactive deflection was seen in the highest SrF samples. Mechanical tensile testing data showed that the stiffness of the composite variant increased with a higher percentage of SrF. Magnetically, the samples with more SrF content had lower saturation magnetization (Ms) and higher coercive field (Hc). The high stiffness and magnetic properties contribute to the limited magnetoaction. This approach to magnetic annealing of magnetic elastomers can be used to 3D print accurate and complex components for high-performance soft robotic applications.

Impact of 3D Printing Extrusion on Magnetically Annealed High Performance Hard/Soft Magnetic Elastomers

Considering the natural abundance of the constituting elements and first-order phase transition (FOPT), LaFe13-xSix-derived compounds have been extensively studied for magnetocaloric effect, a phenomenon that causes the cooling or heating of material when placed in an external magnetic field [1]. They are, however, extremely brittle and mechanically friable, showing rather low thermal conductivities and measurable irreversibility, which thus far could not be eliminated completely. Recently, Pathak et al. [2] reported the first-time discovery of a two-phase, naturally formed at the LaFe2Si stoichiometry rather than LaFe13-xSix compound. LaFe2Si exhibits strongly responsive behaviors without the degradation in properties that can be exploited in weak magnetic fields. However, the phase transition happens rather at low temperatures and the saturation moment is low. We are working on this material to further enhance the phase transition temperature and also to improve the magnetic and mechanical properties of the alloy. In this presentation, we will present the synthesis and characterization of LaFe2-yCoySi. We prepared LaFe2-yCoySi by making the first pre-alloy of FeCoSi and then added Co and melted several times. The alloys were further homogenized by the vacuum suction casting technique, which prepared a 4 to 5 cm long rod with a 6mm diameter of sample. The ferromagnetic to paramagnetic transition temperature increases from 199K for x = 0 to 273K for x = 0.3 and the full width at the half-maximum value of magnetic entropy changes increases significantly with Co doping. We discuss the phase transition, electrical transport, magnetic and magnetocaloric properties of LaFe2-yCoySi compounds.

Phase transition, electrical transport and magnetic entropy change of LaFe2 yCoySi alloys prepared by suction casting

Magnetic elastomers are flexible smart materials that can be manipulated by magnetic fields to achieve reversible mechanical deformation. These highly configurable materials are instrumental in transforming biomedical applications such as artificial muscles, dampeners, and other vibration absorbers. Magnetic elastomer structures must be customizable to satisfy these complex applications leading to the use of fused filament fabrication (FFF) in creating them. FFF is a 3D printing process where material is extruded in 1D lines (infill) to build 2D planes layer-by-layer, resulting in a 3D structure. This research used magnetoactive testing to investigate how varying the internal infill structure affected the mechanical response of the structures within an applied magnetic field. Different infill percentages and infill orientations were tested to account for different mechanical stiffnesses and internal geometries. The elastomers were made by adding 40wt% magnetite (Fe3O4) to a thermoplastic polyurethane (TPU) matrix. Each sample was magnetoactively tested with three different transverse magnetic field orientations (Front, Back and Top). The samples were placed between two electromagnets, and the angle of deflection was recorded as a function of applied field. Maximum angles of deflection for the testing setup were reached when both lower infill percentages, translating to less material in the cross-section of the sample, and lower infill orientations, creating much less crosslinking between infill lines, were used. Transverse fields applied parallel to the print plane (Front, Back sample orientations) demonstrated the most magnetoaction due to less crosslinking constraining the bending stiffness. The anisotropy of the infill structure likely also contributed to the large response from certain samples. It was concluded that for this fixed base material, it is more important to 3D print structures with lower stiffnesses than more net magnetic particulate in achieving the most magnetoaction. According to this data, 3D printed magnetite-TPU structures are viable for creating components easily stimulated by a magnetic field unlocking many possibilities for the creation of useful technological components.

Magnetoactive Properties of 3D Printed Magnetic Elastomer Structures: Effects of Infill Orientation and Infill Percentage

Magnetic elastomers are composite smart materials made up of a flexible polymer and magnetic particulate which mechanically actuate in response to an applied magnetic field (H). They allow for a highly configurable and untethered actuator. To enhance configurability, 3D-Printing allows for great control of the objects meso and macro structure, both in terms of shape geometry and property anisotropy. Specifically, Fused Filament Fabrication (FFF) is a process by which material is extruded in lines (infill) to gradually build up an object through layer-by-layer extrusion. In this study, we explore how multiple FFF structural parameters (infill orientation and infill percentage, and sample orientation relative to H) affect the magnetoactive response of printed Strontium Ferrite (SrF) magnetic elastomer structures. Magnetic elastomers with hard magnetic particulate have the unique advantage of performing more complex actuation, such as rolling, twisting and folding. SrF is an excellent hard magnet candidate given its lower price and greater accessibility compared to NdFeB. Magnetoactive properties are measured by a custom setup where each printed sample beam is suspended and optically tracked for a transverse H up to 0.4 T. For each sample, multiple orientations relative to H are studied. A custom program overlays the digital images for increasing H in order to quantify the magnetoactive deformation that results. The magnetoactive responses exhibited by the various sample types highlight clear design goals for tailoring large and complex magnetoactive actuation modes. In addition to the traditional transverse bending seen from typical (soft) magnetic elastomers, we also observe complex twisting and torquing of the beams in multiple dimensions based upon the printed structure and the sample orientation relative to H. These effects are greatest for the orientations and structures that maximize magnetic anisotropy and minimize the infill crosslinking. This work demonstrates the clear potential to tailor complex magnetoactive responses from FFF-printed hard magnetic elastomers, opening the door to highly complex actuators that can be readily and accessibly designed and created.

Complex Magnetoactuation of 3D Printed Hard Magnetic Elastomers: Effects of Infill Orientation and Percentage

The ability to harness excellent magnetic and optical properties within a heterostructure film composed of a magnetic material and a transition metal dichalcogenide (TMD) semiconductor paves a new pathway for the development of multifunctional sensing devices, information storage technology, etc1. Atomically thin tungsten disulfide (WS2) (thickness â‰¤ 5 nm) has been widely explored as a promising candidate for applications in optoelectronics, spintronics, and valleytronics. The valleytronic property of WS2 can be enhanced when interfacing it with another magnetic material such as iron (Fe), due to the magnetic proximity effect2. However, the growth of this 2D-TMD with controllable thickness, using chemical vapor deposition (CVD), and transferring it onto another substrate (Fe) via a commonly used wet transfer process have remained a challenging task. To overcome this, we employ a combination of pulsed laser deposition (PLD) and sputtering (SP) techniques to grow Fe/WS2 heterostructure films with a controlled interface and desirable magnetic/optical properties. A 5nm thick WS2 film was first grown on MgO substrate using PLD, and a 5nm thick Fe film was then deposited on WS2/MgO using SP. A 2nm thick Ta layer was sputtered on the Fe surface to protect the film from oxidization. X-ray diffraction, Raman and Photoluminescence spectroscopy, and atomic force microscopy confirmed the structure of the heterostructure and the quality of the Fe/WS2 interface. Vibrating sample magnetometry, magneto-optical Kerr effect (MOKE), and magnetic force microscopy indicated that the excellent magnetic properties of Fe are preserved in the Ta/Fe/WS2/MgO heterostructure relative to the Ta/Fe/MgO reference film. MOKE showed a sharp, square magnetic hysteresis loop of Ta/Fe/WS2/MgO with a coercive field (Hc ~ 25 Oe) similar to that of the reference film, Ta/Fe/MgO (Hc ~ 23 Oe). The combined excellent magnetic and optical properties make the Ta/Fe/WS2/MgO heterostructure a promising candidate for a wide range of applications in spintronics, valleytronics, and opto-spincaloritronics3. Our study provides a new, efficient method for the growth of novel 2D van der Waals TMD-based heterostructures with controlled interface properties.

Underline digital video library

Magneto Optical Figure

Magneto Optical Properties of Cobalt

Magnetically Sensitive Electronic Skins for Supervised Folding of Origami Actuators

Reprogrammable Liquid metal/NdFeB/Silicone Composite Magnetic Elastomer

Soft Magnetic Elastomer Composites Enabling Magnetic Actuation and Field Sensing Based on Fiber Optic Interferometry

Power transfer in magnetoelectric resonators

NiMn based Heusler thin films: an amazing class of ferromagnetic shape memory alloys

Impact of 3D Printing Extrusion on Magnetically Annealed High Performance Hard/Soft Magnetic Elastomers

Phase transition, electrical transport and magnetic entropy change of LaFe2 yCoySi alloys prepared by suction casting

Magnetoactive Properties of 3D Printed Magnetic Elastomer Structures: Effects of Infill Orientation and Infill Percentage

Complex Magnetoactuation of 3D Printed Hard Magnetic Elastomers: Effects of Infill Orientation and Percentage

Growth of iron/tungsten disulfide heterostructure films with controlled interface and magnetic properties

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