United States

Recent development of next-generation information storage has been focused on applications exploiting the spin degree of freedom. Much attention has been given to helimagnets in which the direction of the spins spatially rotates in a plane perpendicular to their propagation vector. With application of external magnetic field, the ground state of stripes transforms into various nontrivial spin textures with unique topological numbers, such as skyrmion tubes (1), skyrmion bubbles (2), and magnetic solitons (3, 4). In this talk, we will show that the pure helical orders with a period of approximately 3.6 nm was observed in the single crystals of meta-magnet MnCoSi5. To elucidate the internal 3D magnetic spiral configurations in real space, the multi-azimuth and multi-angle imaging approach of Lorentz transmission electron microscopy (LTEM) was applied, see Figure 1. The sinusoidal modulation of the line profile outlines the stripes with a period (L) of 3.6 nm along the [001] direction. The short-period spin order is further verified by satellite spots adjacent to the main reflections in the enlarged selected area electron diffraction (SAED) patterns. The serial-tilting characterization for the [100] thin plate confirms the stable appearance of periodic stripes along different crystallographic directions. These results strongly imply that a robust and ultrafine helical magnetic order exists in the non-chiral metallic metamagnet MnCoSi at room temperature. The discovery of nanometric spin order in MnCoSi can path a way towards interesting spintronic applications, notably the realization of a room-temperature emergent inductor.&lt;br&gt;

**References:**&lt;br&gt;
(1) M. T. Birch, D. Cortés-Ortuño, L. A. Turnbull, et al., Nat. Commun. 11 (1), 1726 (2020).&lt;br&gt;
(2) X. Z. Yu, Y. Onose, N. Kanazawa, et al., Nature 465 (7300), 901-904 (2010).&lt;br&gt;
(3) B. Roessli, J. Schefer, G. A. Petrakovskii, et al., Phys. Rev. Lett. 86 (9), 1885-1888 (2001).&lt;br&gt;
(4) T. Nagai, K. Kimoto, K. Inoke, et al., Phys. Rev. B 96 (10) (2017).&lt;br&gt;
(5) B. Ding, J. Liu, H. Li, et al., Adv. Funct. Mater. 32 (19), 2200356 (2022).&lt;br&gt;

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MMM 2022

Observation of Short Period Helical Spin Order in Nonchiral Centrosymmetric Helimagnet MnCoSi

Recent development of next-generation information storage has been focused on applications exploiting the spin degree of freedom. Much attention has been given to helimagnets in which the direction of the spins spatially rotates in a plane perpendicular to their propagation vector. With application of external magnetic field, the ground state of stripes transforms into various nontrivial spin textures with unique topological numbers, such as skyrmion tubes (1), skyrmion bubbles (2), and magnetic solitons (3, 4). In this talk, we will show that the pure helical orders with a period of approximately 3.6 nm was observed in the single crystals of meta-magnet MnCoSi5. To elucidate the internal 3D magnetic spiral configurations in real space, the multi-azimuth and multi-angle imaging approach of Lorentz transmission electron microscopy (LTEM) was applied, see Figure 1. The sinusoidal modulation of the line profile outlines the stripes with a period (L) of 3.6 nm along the [001] direction. The short-period spin order is further verified by satellite spots adjacent to the main reflections in the enlarged selected area electron diffraction (SAED) patterns. The serial-tilting characterization for the [100] thin plate confirms the stable appearance of periodic stripes along different crystallographic directions. These results strongly imply that a robust and ultrafine helical magnetic order exists in the non-chiral metallic metamagnet MnCoSi at room temperature. The discovery of nanometric spin order in MnCoSi can path a way towards interesting spintronic applications, notably the realization of a room-temperature emergent inductor. 

**References:** 
(1) M. T. Birch, D. Cortés-Ortuño, L. A. Turnbull, et al., Nat. Commun. 11 (1), 1726 (2020). 
(2) X. Z. Yu, Y. Onose, N. Kanazawa, et al., Nature 465 (7300), 901-904 (2010). 
(3) B. Roessli, J. Schefer, G. A. Petrakovskii, et al., Phys. Rev. Lett. 86 (9), 1885-1888 (2001). 
(4) T. Nagai, K. Kimoto, K. Inoke, et al., Phys. Rev. B 96 (10) (2017). 
(5) B. Ding, J. Liu, H. Li, et al., Adv. Funct. Mater. 32 (19), 2200356 (2022). 

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technical paper

#### Welcome to the 67th Annual Conference on Magnetism and Magnetic Materials, MMM 2022!

The Conference was held from October 31 to November 4 and offers both in-person and on-demand content.

MMM 2022 is sponsored jointly by AIP Publishing and the IEEE Magnetics Society. Members of the international scientific and engineering communities interested in recent developments in fundamental and applied magnetism are invited to attend and contribute to the technical sessions. The technical program will include invited and contributed papers in oral and poster sessions, invited symposia, a tutorial, and several special sessions. This Conference provides an outstanding opportunity for worldwide participants to meet their colleagues and collaborators and discuss developments in all areas of magnetism research.

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Lanthanide dopants in oxide hosts provide excellent spin-photon interfaces for quantum technologies, including by mediating microwave to optical quantum transduction (converting a collective spin excitation to an optical excitation), and for quantum memories. The description of magnetic dipole transitions in lanthanides using model Hamiltonians principally relies on existing experimental fit parameters for terms in the Hamiltonian like the effect of the crystal field on the 4f elections. [1] Here, we deploy an ab initio extraction of crystal field parameters explored by Dadi Dai et al. [2] With ab initio, we extracted crystal field parameters in Er defects in hosts like Y2O3, and in combining the extracted crystal field parameters with the effective operator Hamiltonian approach we were able to compare the theoretical crystal field energy correction with experimental values directly and obtained a relatively good match. In further studies weâ€™re exploring a more systematic prediction of crystal field levels to pave the path for a wide search of lanthanide doped spin-photon systems. We acknowledge funding from NSF DMR-1921877.

Ab initio Crystal Field Splittings for Lanthanide Dopants in Oxide Materials for Quantum Information

Interfacial properties of two-dimensional (2D) van der Waals material/magnetic material heterostructures are crucial for applications in spintronics and valleytronics. Inspired by the recent observation of room temperature ferromagnetic ordering in 2D MoS2 induced by the ferrimagnetic yttrium iron garnet (YIG) and the antiferromagnetic exchange coupling between MoS2 and YIG in a MoS2 / YIG heterostructure [1], investigation into the proximity-mediated spin properties of such heterostructures has become a topic of global interest. Nonetheless, a full understanding of the magnetic proximity effect (MPE) and its temperature and magnetic field evolution in these systems is lacking. In this study, we have used biphase iron oxide (Fe3O4 + Fe2O3) as the magnetic layer and the MPE has been probed in Pt / Tungsten Disulfide / biphase iron oxide heterostructures through a comprehensive investigation of their magnetic and transport properties using magnetometry, transverse susceptibility, four-probe resistivity, and anomalous Hall effect (AHE) measurements. Density functional theory (DFT) calculations are performed to complement the experimental findings. We find that the presence of monolayer Tungsten Disulfide flakes reduces the magnetization of biphase iron oxide and hence the total magnetization of Pt / Tungsten Disulfide / biphase iron oxide above the Verwey transition temperature of Fe3O4 (TV). However, the enhanced magnetization is achieved at T < TV. In the latter case, a comparative analysis of the transport properties of the Pt / Tungsten Disulfide / biphase iron oxide heterostructure and the Pt / biphase iron oxide heterostructructures from the AHE measurements reveals a ferromagnetic coupling at the Tungsten Disulfide / biphase iron oxide interface. Our study forms the foundation for understanding MPE-mediated interfacial properties and paves a new pathway for designing 2D van der Waals material/magnet heterostructures for spin-based device applications 

**References** (1) Tsai, S. P.; Yang, C. Y.; Lee, C. J.; Lu, L. S.; Liang, H. L.; Lin, J. X.; Yu, Y. H.; Chen, C. C.; Chung, T. K.; Kaun, C. C.; Hsu, H. S.; Huang, S. Y.; Chang, W. H.; He, L. C.; Lai, C. H.; Wang, K. L. Room-Temperature Ferromagnetism of Single-Layer MoS2 Induced by Antiferromagnetic Proximity of Yttrium Iron Garnet. Advanced Quantum Technologies 2021, 4, 2000104. https://doi.org/10.1002/qute.202000104.

Proximity Enhanced Anomalous Hall Transport in Biphase Iron Oxide/Tungsten Disulfide Heterostructures

The actual mechanisms occurring at interfaces underlying the Dzyaloshinskii-Moriya interaction (i-DMI) remain largely an open question in nanomagnetism. In this study, we investigate the origin of the i-DMI, aiming at estimating how independent the DMI contributions of the two interfaces of a FM layer are and what their relative weight in the effective DMI amplitude is. The effective DMI is measured by the study of the asymmetric domain wall propagation in the presence of an in-plane magnetic field, in Pt|Co|M stacks. These measurements are completed by Brillouin light scattering (BLS) measurements. We then explore the correlation between the effective i-DMI and the properties of metal M, namely, its atomic number, electronegativity, and work function. A clear linear relationship is found between the i-DMI and the work function difference at the Co|M interface (ΔΦ) [1,2]. We define Δφ = φM - φCo. This result is a strong evidence of the independent DMI contributions of the two interfaces for the chosen Co thickness (1 nm). These findings may guide the optimization of the magnetic properties of future spintronic devices.
This work has been supported by DARPA TEE program grant (MIPR HR-0011831554), ANR grant TOPSKY (ANR-17-CE24-0025), FLAG-ERA SographMEM (ANR-15-GRFL-0005), and the Horizon2020 Framework Program of the European Commission, under FET Proactive Grant Agreement No. 824123 (SKYTOP) and under Marie Sklodowska- FQ Curie Grant Agreement No. 754303 for supporting J.P.G together with the LABEX LANEF in Grenoble (ANR-10-LABX-0051). Univ. Paris-Saclay, CNRS INP, Sesame IMAGeSPIN project (nEX039175) and the LABEX NanoSaclay (ANR10 LABX0035, BLS@PSay and SPiCY projects) are acknowledged for the BLS equipment. 
**References** [1] F. Ajejas et al., Phys. Rev. Mat., June 2022
[2] Y.-K. Park et al., NPG Asia Mater. 10, 995 (2018)
 
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Interfacial potential gradient modulates Dzyaloshinskii Moriya interaction in Pt|Co|Metal multilayers

Spin-orbit torque characterization techniques generally require Hall cross that generally demands lithography resources and time. As the interest in exploring materials for improved SOT performance surges, an efficient technique to characterize SOT efficiencies with minimal processes, equipment, and time is highly desirable. Here, we demonstrate a lithography-free technique to determine the spin-orbit torque efficiency in perpendicular magnetic anisotropy ferromagnetic heterostructure. By utilizing a customized fzour-point probe in a rhombus geometry, harmonic Hall measurement was performed on a blanket films of Pt/Co/Ti structure to characterize the spin-orbit torque efficiency. Due to the non-uniform current distribution across the blanket film, a correction factor is experimentally evaluated using the ratio of the damping-like field measured on the blanket film to that of a fabricated Hall device with identical material heterostructure. Additionally, this correction factor is analytically derived and experimentally shown to be determined by the configuration of the probes and is independent of the structure material. Our measurement reveals that by performing a single calibration process for the particular set of probes, the same correction factor was validated on a second ferromagnetic heterostructure, Ti/Pt/Co/Ta hence it can be applied to other SOT films stack measurements. Our four-probe harmonic Hall technique provides an alternative and swift way for SOT investigations by eliminating multiple lithography processes necessary in conventional approaches.

Blanket Film Spin Orbit Torque Characterization via Four Probe Measurement

Mn3Pt is a non-collinear antiferromagnet with an fcc crystal structure and magnetic moments on the Mn atoms that are at an angle of 120° with respect to each other. This arrangement breaks the cubic symmetry and allows for the existence of the anomalous Hall effect. Here we measure an anomalous Hall effect in Mn3Pt thin films that is only present at temperatures below 270K. This can be explained by a transition from a collinear (above 270K) to a non-collinear (below 270K) antiferromagnetic phase, which is characterized by a sudden change in resistance of the film. Moreover, because of mirror symmetry breaking due to the magnetic structure, we expect to generate exotic spin-torques with a spin-polarization component along the out-of-plane direction, which is unlike the conventional in-plane spin polarization direction. This allows for efficient and deterministic switching of out-of-plane magnetized materials through spin-orbit torques.
References

GB-04 (FOC-05)

High-throughput study of spin and orbital transport in magnetic materials

Yuta Yahagi1, 2, Jakub Zelezny3

1Applied Physics, Tohoku University, Sendai, Miyagi, Japan, 2NEC-AIST Quantum Technology Cooperative Research Laboratory, NEC Corporation, Tsukuba, Ibaraki, Japan, 3Institute of Physics, Czech Academy of Science, Prague, Czechia


Abstract Body We study the spin Hall effect (SHE) and the orbital Hall effect (OHE) in magnetic materials using automatic high-throughput calculation scheme. The SHE is a phenomenon in which an applied electric field induces a spin current. This effect plays a key role in various spintronics devices. Although the SHE has been researched mainly in nonmagnetic materials, SHE in magnetic materials has gained a considerable attention recently as they can exhibit a large SHE[1]. The OHE, a phenomenon in which electric field generates a flow of orbital angular momentum, has also been attracting attention as a new driving mechanism of devices [2]. For future application, exploring materials with large SHE or OHE is demanded.

In this study, we perform a systematic evaluation of the spin Hall conductivity (SHC) and the orbital Hall conductivity (OHC) of select materials from MAGNDATA[3], a database of magnetic materials. We target collinear materials both ferromagnets and antiferromagnets, and evaluate their intrinsic contributions of SHC and OHC based on Kubo-formula.

Figure 1 shows the results of SHC and OHC of 84 materials. The OHCs in most materials are nearly ten times larger than the SHCs. Interestingly, the Mn3Pt has a colossal OHC reaching about 14000 (hbar/e)S/cm, which is higher than either OHC of Mn (~10000) and Pt (~2000) [4], suggesting the importance of the material structure. Further analysis of both theoretical aspect and data science will be presented at the conference. 
**References** [1] C. Qin, et al., Phys. Rev. B 96, 134418 (2017); Y. Zhang et al., New J. Phys. 20, 7 (2018).
[2] H. Kontani, et al., J. Phys. Soc. Jpn., 76, 103702 (2007).
[3] S.V. Gallego et al., J. Appl. Crystallogr. 49, 1750 (2016).
[4] D. Jo, D. Go, and H-W. Lee, Phys. Rev. B 98, 214405 (2018). 
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Anomalous Hall Effect and Exotic Torques in Non Collinear Antiferromagnet Mn3Pt

Spin-orbit coupling (SOC) plays a vital role in spin-to-charge interconversion in heavy metal (HM)-ferromagnet (FM) bilayer structures [1]. Spin pumping is an efficient method to generate pure spin current by the precessional motion of magnetization, which transfers angular momentum to HM. The efficiency of spin pumping is quantified by an interfacial parameter called spin-mixing conductance (g↓↑). Electrical detection of spin current is possible via inverse spin Hall effect (ISHE) which converts spin current into charge current. The efficiency of spin-to-charge interconversion is quantified by spin Hall angle (θSH) [2]. The θSH of heavy metal highly depends on its crystalline phase and the effect of the seed layer on the phase of HMs is largely overlooked. Here, we report the effect of seed permalloy (Ni80Fe20, Py) layer thickness on the Tantalum (Ta) and Tungsten (W) crystalline phase and its θSH. We have observed a structural phase transition in Ta as a function of seed layer thickness (tPy) affecting the θSH of the Ta layer. Due to strain at the interface between crystalline Py and Ta, Ta exhibits a mixed-phase (α+β) on the seed permalloy layer when tPy > 12 nm. However, Ta nucleates as α-Ta on Py with tPy < 8 nm, Py does not exhibit prominent crystalline nature. The phase transition of Ta is primarily attributed to strain at the Py/Ta interface which is not observed in both Py(tPy)/W(10) and Co40Fe40B20 (tCFB)/Ta(18) bilayer structure. Ferromagnetic resonance (FMR) based spin pumping shows that effective damping is enhanced for all samples. The maximum g↓↑ of 10.1×1018 m-2 is observed for Si/Py(20)/Ta(18) and the minimum value of 7.9×1018 m-2 for Si/Py(8)/Ta(18) which corresponds to (α+β)-phase of Ta and α-phase of Ta, respectively. The estimated θSH for (α+β)-Ta is 0.15 ± 0.009, which is higher than α-Ta. The combined effect of symmetry breaking and low longitudinal resistance are the primary reason for the high g↓↑ and θSH. Our systematic study provides an insight into Ta phase transition via seed layer thickness and gives an alternative route for tuning [3]. 
**References*** [1] A. Brataas, Y. V. Nazarov, and G. E. W. Bauer, Finite-Element Theory of Transport in Ferromagnet–Normal Metal Systems, Phys. Rev. Lett. 84, 2481 (2000).
[2] Y. Tserkovnyak, A. Brataas, and G. E. W. Bauer, Nonlocal Magnetization Dynamics in Ferromagnetic Heterostructures, Rev. Mod. Phys. 77, 1375 (2005).
[3] K. Sriram, A. Haldar, and C. Murapaka, Effect of Seed Layer Thickness on the Ta Crystalline Phase and Spin Hall Angle, Nanoscale 13, 19985 (2021). 
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Effect of seed layer thickness on Ta crystalline phase and spin Hall angle

Soft magnetic composites(SMCs) consist of ferromagnetic particles, in the micrometer-range which are embedded in an electrically insulating material, in order to reduce the eddy-currents in the high-frequency regime. We want to utilize numerical simulations in order to optimize such materials in terms of power-loss and permeability. The problem one faces is that the samples have macroscopic sizes, however if one would want to resolve these materials on the micro-scale, it would limit the total simulation size to a few micrometers. Introducing a truncated geometry or cut-off would also not solve this problem as demagnetization effects would come into play for any finite sized sample. However due to the torus-like shape of the sample, the magnetic flux closure reduces the strayfield to zero. To overcome these issues we developed and implemented our own method for calculating the micromagnetic strayfield with periodic boundary conditions(PBCs)[1]. PBCs allow us to simulate an infinite sample and therefore avoid the demagnetization effects. A complete magnetic simulation framework including PBCs will be presented with which the spatially- and time-resolved magnetization response to an external field is simulated. The model will be validated among other things by reproducing experimental setups that have successfully reduced the power-loss of SMCs. Suetsuna et al.[2] have shown that the power-loss reduces by roughly half when the sample is exposed to a magnetic field during annealing, because an aligned anisotropy direction is induced. This was replicated in the simulation and as can be seen in figure 1 the simulated power-loss Pm decreases by half when an aligned anisotropy is applied, without altering the relative permeability mur. 

**References** 
[1] Bruckner, Florian, et al. "Strayfield calculation for micromagnetic simulations using true periodic boundary conditions." Scientific Reports 11.1 (2021): 1-8.
[2] Suetsuna, Tomohiro, et al. "Soft magnetic composite containing magnetic flakes with in-plane uniaxial magnetic anisotropy." Journal of Magnetism and Magnetic Materials 473 (2019):
416-421. 

![](https://s3.eu-west-1.amazonaws.com/underline.prod/uploads/markdown_image/1/image/1c066203e20a987f28c178a793a3e69b.png) 

Fig. 1 Powerloss Pm and permeability mur were calculated from hysteresis simulations utilizing the SMC model with aligned and random anisotropy.

Simulation of Soft Magnetic Composites with Periodic Strayfield Calculation

Artificial spin ice lattices consist of extended arrays of dipole coupled nanomagnets. This relatively simple system has seen a striking amount of applications, such as mimicking spin frustration, reconfigurable magnonic crystals, and in the last years it displayed potential for novel forms of computation. We have recently investigated the effects of the internal texture of these nanomagnets, specifically the thermal behavior, and found the excitation of magnons, and additional fluctuations at the ends of the nanomagnet. These effects offer a different view of the effect of temperature on the magnetism than the traditional flipping of the Ising spin. Here, we present measurements using AC susceptibility and temperature dependent MOKE of artificial spin ice structures, which indicate the presence of these additional texture fluctuations. It is shown that, even though they exist on a different length scale than the binary switch of the internal magnetization, both types of fluctuations can be tuned through the interaction strength of the mesospins. In addition, we present a detailed simulation study that shows the effects of coupling of these texture fluctuations across a gap, both in a double magnet configuration and an ASI vertex, and capture these fluctuations in energy landscapes. We determine the energy barriers, eigenmodes, and curvatures of the energy landscapes at the metastable minima and relate them to the attempt frequencies of the system. These investigations of the internal texture could lead to a rethinking of the artificial spin ice lattice, in which case the internal textures could be used to mimic magnetic effects on different length scales.

Effects of thermal fluctuations within and among the magnetic textures in artificial spin ice

The ability of certain magnetic materials to change their entropy and/or temperature with the application and removal of a magnetic field (magnetocaloric effect, MCE) is a physical phenomenon that could lead to the realization of clean, energy-efficient heat pumping systems. We report a series of LaFe11.8Si1.1X0.1 compounds, where X = Al, Ga, and In, added in small concentrations, substantially reduce brittleness intrinsic to unsubstituted La(Fe1-xSix)13, while preserving or enhancing their giant MCEs [1]. Room temperature powder X-ray diffraction confirms formation of LaFe11.8Si1.1X0.1 adopting the NaZn13-type structure as major phases, with ~10 to 15% of Î±Fe impurity. Surprisingly, relatively large amounts of Î±Fe do not deteriorate the magnetic field-induced entropy change (Î”S), yet the resultant alloys have much improved mechanical stability. The corresponding maximum Î”S are -18, -17, and -13 J kg-1 K-1 for X = In, Al, and Ga, respectively, in Î”H = 2 T in the vicinities of their respective Curie temperatures. The Curie temperatures of LaFe11.8Si1.1X0.1 materials can be increased to room temperature and above by hydrogenation, preserving the giant MCE. For example, a fully hydrogenated LaFe11.8Si1.1In0.1H2.3 exhibits maximum Î”S close to -16 J kg-1 K-1 at T~344 K and Î”H =2 T. This work was supported by the Division of Materials Science and Engineering of the Office of Basic Energy Sciences of the U.S. DOE. Ames Laboratory is operated for the U.S. Department of Energy (DOE) by Iowa State University under Contract No. DE-AC02-07CH11358. AKP acknowledges the finanacial support from faculty startup fund from the Deanâ€™s Office, School of Arts and Sciences, SUNY Buffalo State.

Tailoring mechanical properties and magnetocaloric effect in LaFe11.8Si1.2 zXzHy (X = Al, Ga, In)

Body Magnetic particle imaging (MPI) is a technique to visualize magnetic nanoparticles with high spatial and temporal resolutions based on nonlinear magnetization response.1
One of major challenges toward clinical MPI system is how to implement low ac excitation fields. For brain MPI particularly,2 a 24 kHz excitation field intensity with amplitude over 3.5
mT may induce peripheral nerve stimulation on human head.3 However, low-field MPI scenario degrades spatial resolution since the detected signal has no harmonic components but high
contamination from the excitation fields. Previously, we applied 1 MHz excitation field to elevate signal-to-noise ratio of receive coil.4 To further decontaminate magnetization signal
spectrally, we used magnetoresistive (MR) sensor to transform monotone signal into harmonic-rich one and reconstructed phantom image from odd harmonic components.5 Extensively,
MR sensor can be used to map quasistatic stray field of magnetic nanoparticles.6
Here, we will report the use of a 6×6 channels array of TDK Nivio xMR sensors to detect sub-pT magnetic signal and obtain its spatial distribution. While each sensor is operated at 5 V,
signal processing circuit rises its sensitivity to 20 mV/ pT at 10 kHz with 0.25 pT noise level. We used a 40-turns coil with 1 mm diameter and 5 mm length to represent magnetic moment.
The distance between MR sensor and the coil (dx) was 250 mm [Fig. 1(a)]. From Fig. 1(b), MR sensor recognizes magnetic signal from mini coil fed with a 10 kHz ac current. Magnetic
field detected by the sensor (Hd) is linear with coil input current (i). Furthermore, we simultaneously recorded the signals from 36 sensor channels to map at 200 Hz. We set dx=50 mm to
obtain high contrast showing coil position relative to the array. From Fig. 2, the change in field polarity is observable from frames (i), (ii), (iii), and (iv) with channel c16 as reference. This
result highlights usability of MR sensor array for low-field MPI system. 

**References:** 

1. B. Gleich and J. Weizenecker, Nature, 435, 1214 (2005). 
2. M. Graeser, F. Thieben and T. Knopp, Nat. Commun., 10, 1936 (2019). 
3. A. A. Ozaslan, M. Utkur and E. U. Saritas, Int. J. Mag. Part. Imag., 8, 2203028 (2022). 
4. S. B. Trisnanto and Y. Takemura, Phys. Rev. Appl., 14, 064065 (2020). 
5. S. B. Trisnanto, T. Kasajima and Y. Takemura, Appl. Phys. Express, 14, 095001 (2021). 
6. S. B. Trisnanto, T. Kasajima and Y. Takemura, J. Appl. Phys. 131, 224902 (2022). 

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Observation of Short Period Helical Spin Order in Nonchiral Centrosymmetric Helimagnet MnCoSi

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Ab initio Crystal Field Splittings for Lanthanide Dopants in Oxide Materials for Quantum Information

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