United States

Spin transfer (ST) effect is a consequence of angular momentum conservation [1-3], one of the three fundamental conservation laws in nature. We use fully quantum simulations of scattering of spin-polarized electron wavepacket by a ferromagnet modelled as a 1d spin-1/2 chain [4], as illustrated in Fig.1, to show that energy and momentum conservation laws impose strong restrictions on the characteristics of magnetic excitations generated by spin transfer. We found that two groups of magnons are generated by ST in this 1d system, forward-propagating magnons with large energy Ef, and backward-propagating magnons with small energy Eb . Analysis shows that the backward-propagating magnons are generated by the reflected electron component, while the forward-propagating magnons -by the transmitted electron component, with the values of energy and momenta of the generated magnons determined by the changes of the corresponding characteristics of the electron wave [Fig.2]. We also show a converse effect – dependence of the scattered electron’s characteristics on the dynamical characteristics of the magnetic system. In particular, variations of magnetic anisotropy result in the variations of energy of the scattered electrons, and of the probability of electron reflection. For large anisotropy, electron reflection is completely suppressed, and only one group of magnons is generated. Our results demonstrate that quantum magnetism plays an important role in magnetoelectronic phenomena. This work was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award # DE-SC0018976.References: 1. J. Slonczewski, J. Magn. Magn. Mater. 159, L1 (1996). 2. L. Berger, Phys. Rev. B 54, 9353 (1996). 3. D. Ralph and M. Stiles, J. Magn. Magn. Mater. 320, 1190 (2008). 4. P. Mondal, et al, Phys. Rev. B 99, 094431 (2019).

MMM 2020

Energy and momentum conservation in spin transfer.

The 65th Annual Conference on Magnetism and Magnetic Materials (MMM 2020) was held in a virtual form. The COVID-19 pandemic, with its associated uncertainty about international travel and the ability to gather in large groups, meant that the Steering Committee decided to cancel the face-to-face meeting that had been planned in Palm Beach, Florida November 2-6, 2020.

We were reluctant to give up the benefits of meeting face-to-face, and know that shifting to a virtual conference is a significant change for this community. Nevertheless, we are first and foremost concerned about the health and safety of all our Conference participants and their loved ones on returning home after travelling.

The MMM 2020 Steering Committee was working exceptionally hard, along with our sponsors, the IEEE Magnetics Society and AIP Publishing, to make this event serve the needs of our participants, who live in time zones all around the globe, in the best possible way. 

You need a ticket to explore this event.

If you have already registered for MMM 2020, and you have already created an account, then you
just need to login (above).

If you have already registered for MMM 2020, but you have not yet created an account, then you
need to click on &quot;create an account&quot; (above) and then login.

Forgot your password? Go to
https://www.underline.io/log-in

If you have not yet registered for MMM 2020 but would like to do so, go to
https://magnetism.org/register

Still need help? Contact our team!


technical paper

Multiferroics attracts great attention in the present time due to their very promising technological applications. In the so-called multiferroics of spin origin [1] phenomenon of giant magnetoelectric response was observed [2,3]. Two mechanisms of magnetic ordering induced ferroelectricity, namely inverse Dzyaloshinskii-Moriya and spin-dependent p-d hybridization, imply noncollinear magnetic structure [1], which can appear for example due to the frustration of exchange interaction. This makes research on such incommensurate spin structures as helicoids very important since their properties determine electric polarization. Recently we propose a theoretical description of spiral plane flops in anisotropic frustrated helimagnets [4]. Using smallness of anisotropic interactions in comparison with the exchange one, energies of competing spin textures were described perturbatively and simple equations for the flop fields were derived. Notably, formulas have a similar form with the spin-flop field in uniaxial antiferromagnets. Moreover, the theory was successfully applied to the experimental data on several magnets. In the present research, we further proceed with the theoretical study of anisotropic frustrated antiferromagnets [5]. We show, that if there is competing commensurate spin ordering along with two conventional phase transitions at small magnetic fields (spin-flop and spiral pane flop, see Fig.1 (a) and (b)) there appears a possibility to induce helical ordering using an external magnetic field (see Fig.1 (c), (d) and (e)). We propose and describe theoretically three sequences of phase transitions, where at zero field conventional antiferromagnetic ordering is the ground state. We successfully apply our approach for the description of phase transitions in MnWO4 [6] (scenario shown in Fig. 1 (c)). Furthermore, the scenario shown in Fig. 1 (e) was observed experimentally in Ref. [7] after our research was published. To the best of our knowledge, scenario Fig. 1 (d) has not been found yet and it seems to be an interesting experimental problem.References: [1] Y. Tokura, S. Seki, and N. Nagaosa, Rep. Prog. Phys. 77, 076501 (2014), and references therein [2] S.-W. Cheong and M. Mostovoy, Nat. Mater. 6, 13 (2007), and references therein. [3] Y. Tokura and S. Seki, Adv. Mater. 22, 1554 (2009). [4] O. I. Utesov and A. V. Syromyatnikov, Phys. Rev. B 98, 184406 (2018). [5] O. I. Utesov and A. V. Syromyatnikov, Phys. Rev. B 100, 054439 (2019). [6] M. V. Gvozdikova, T. Ziman, and M. E. Zhitomirsky, Phys. Rev. B 94, 020406(R) (2016). [7] J. Lass, et. al., Phys. Rev. B 101, 054415 (2020).

Formation of Spiral Ordering by Magnetic Field in Frustrated Anisotropic Antiferromagnets

LuFeO3 (LFO) a member of the orthoferrite (RFeO3) family, holds the promise of replacing the well-known room temperature multiferroic, BiFeO3 [1]. LFO nanoparticles with and without Ho doping (i.e., Lu1-xHoxFeO3 with 0 ≤ x ≤ 1) were synthesized using the hydrothermal method [2]. Rietveld refinement of the XRD data (Fig.1) for x = 0 (0.05) reveal the presence of both the hexagonal (h) P63cm and orthorhombic (o) Pnma phase fractions as 96% (6%) and 4% (94%), respectively. Further Ho doping resulted in pure o- structure. The lattice parameters (a, b, c) follow Vegard’s law ensuring the replacement of Lu atoms by Ho atoms. The common characteristics of o- RFeO3 are i) negligible ferroelectric polarization, ii) ordering of Fe3+ moments antiferromagnetically via Fe3+-O2--Fe3+ super-exchange interaction in ac plane and net magnetic moment along b direction for T < TN1 ≈ 600 K, iii) ordering of R3+ moments at T < TN2 ≈ 10 K, iv) possible re-orientation of spins (SR) from b to c direction between TN1 and TN2 owing to the R3+-O2--Fe3+ interaction [3, 4]. To understand the effect of Ho doping on the magnetic properties of Lu1-xHoxFeO3 with 0 ≤ x ≤ 1, the magnetization (M) has been measured as a function of temperature at a magnetic field of 100 Oe in both the zero-field-cooled (ZFC) and field-cooled (FC) modes (Fig.2). For x = 0, the SR is observed at 120 K. In this case, the SR is attributed to h- LFO since in o- LFO, no SR has been reported [5, 6]. For x = 0.05, SR could not be observed even at the lowest measurement temperature of 3 K presumably due to the weak R3+-O2--Fe3+ interaction. Further increase in Ho concentration progressively strengthens the R3+-O2--Fe3+ interaction and hence TSR shifts to higher temperatures with increasing x, as shown in Fig.2. When the M due to Fe3+ moments is equal and opposite to M due to Ho3+ moments, compensation (comp) occurs and the net M goes to zero. For x = 0.3 to 0.6, Tcomp is found to increase with Ho concentration. This study establishes that the Ho doping stabilizes O-structure beyond x > 0.05 and increases the TSR from 0 in o-LFO to 57.8 ± 0.2 K in o-HFO.References: 1. Chowdhury, U. et al. 1–12 (2017). 2. Leelashree, S et al.. J. Supercond. Nov. Magn. (2019) doi:10.1007/s10948-019-5114-4. 3. Zhou, Z et al.. J. Alloys Compd. 583, 21–31 (2014). 4. Yamaguchi, T. J. Phys. Chem. Solids 35, 479–500 (1974). 5. Liu, J. et al. Adv. Funct. Mater. 28, 1–7 (2018). 6. Zhu, W, et al.. Appl. Phys. Lett. 100, 4–8 (2012).

Ho doping induced spin reorientation in O- Lu1-xHoxFeO3 (x = 0 to 1)

Europium chromite (EuCrO3) is a multifunctional material presenting physical and chemical properties that are strongly influenced by the rare-earth ion lying on the A-site of an orthorhombic distorted perovskite structure [1]. EuCrO3 does also present a variety of spin interactions that are highly dependent on temperature (T), leading to a spin-canting antiferromagnetic phase with a Néel temperature (TN) close to about 170 K [2]. In the present work, the dynamics of the spins and the structural parameters of as prepared and thermal treated (T = 1073 K, time = 24 h) samples of Eu1−xFexCrO3 (x = 0, 0.10 and 0.20) were investigated. The ac-magnetic susceptibility (χac) was measured near TN for frequencies (f) in the range 10-104 Hz, magnitude of the ac magnetic field of 10 Oe and for 5 ≤ T ≤ 300 K. X-ray diffraction data were used for measuring the lattice parameters (a, b and c) and the bonding angle θB (Cr3+–O(2)–Cr3+), for 100 ≤ T ≤ 300 K. The maximum in χac was found to shift to higher values of T for increasing values of f. The Voguel-Fulcher law was used for analyzing χac yielding values for the characteristic relaxation time τ0, activation energy Ea/kB and TG, respectively, in the ranges 1.1 - 4.2 ns (3.1 - 3.6 ps), 29.4 - 45.5 K (46.5 - 47.2 K) and 159 - 166 K (170 -173 K) for the as prepared (thermal treated) samples. The super-exchange parameter J ~ cos4[(180-θB)/2]/d7, where d is the length of the Cr-O(2) bound [3], was also obtained for both as prepared and thermal treated samples yielding a good correlation of the values of J with the corresponding ones of TG. Work partially supported by CNPq, CAPES, FACEPE and FINEP (Brazilian Agencies).References: 1 - J. M. Marín Ramírez, H. V. S. Pessoni, A. Franco Jr. and F.L.A. Machado, J. Alloys Compd., Vol. 690, p.315 (2017). 2 - D. R. Ratkovski, J. M. Marín Ramírez, P. R. T. Ribeiro et all., J. Alloys Compd., Vol. 724, p.501 (2017). 3 - J. S. Zhou and J. B. Goodenough, Phys. Rev. B, Vol. 77, p.132104 (2008).

On the Correlation of the Magnetic Properties with the Structural Parameters in Fe-doped Europium Chromite

A variety of chemical and physical procedures could be used for synthesis of magnetic nanoparticles. However, these methods are fraught with many problems with the use of toxic solvents, generation of hazardous by-products, and high energy consumption. Accordingly, there is a vital need to develop environmentally benign procedures for the synthesis of nanoferrites. A promising approach to achieve this objective is to exploit the array of biological resources in nature. Indeed, over the past several years, plants, have been used for production of low-cost, energy-efficient, and nontoxic metallic nanoferrites. Plant-mediated synthesis of nanoparticles is a green chemistry approach that connects nanotechnology with plants. This innovation is particularly compensating as far as decreasing the poisonous quality caused by the conventionally integrated NPs. Aloe Vera leaf extract is a medicinal agent with multiple properties including an antibacterial effect. Moreover, the constituents of Aloe Vera leaves include lignin, hemicellulose, and pectins which can be used in the reduction of nanoferrites. The magnetic nanoferrites (Fe, Co, Ni) were prepared by an eco-friendly hydrothermal method using an Aloe Vera plant extract solution as both a reducing and stabilizing agent. Magnetic nanoferrites were characterized using FTIR, XRD, VSM and SEM. Cytotoxicity were obtained using the MTT assay. X-ray diffraction analysis also demonstrated that the size range of the nanoferrites exhibited average diameters of 7- 19 nm. Results showed that all the metallic nanoparticles are magnetic with values Fe= 52 emu/g, Co= 33 emu/g and Ni=7.1 emu/g. The magnetic nanoferrites exhibited high cell viability rate at high concentrations signifying their non-toxic property. The magnetic nanoferrites produced in this study by green synthesis methodology from leaf extract of Aloe Vera needs to be further evaluated and could find greater biomedical application.References: K. Schulze, A. Koch, B. Schopf and A. Petri, Journal of Magnetism and Magnetic Materials, Vol. 293, pp. 419-432, (2005). S. Das, C. Dickinson, F. Lafir and D. Brougham, Green Chemistry, Vol. 14, pp. 1322–1334, (2012). M. Ferrari, Nature Reviews Cancer, Vol. 5, pp.161-171, (2005). M. Venkatachalam, G. Parthasarathy and P. Gowthaman, Imperial Journal of Interdisciplinary Research (IJIR), Vol. 2, pp. 1570-1575, (2016). T. Neuberger, B. Schopf and H. Hofmann, Journal of Magnetism and Magnetic Materials, Vol. 293, pp. 483–496, (2005).

Green Synthesis of Magnetic Fe3O4, CoFe2O4 and NiFe2O4 from Aloe Vera Extract for future Biomedical Applications

Magnetic order at the atomic scale has received considerable attention due to its potential application in spin transistors1-2, quantum computing3-4 , and ultra-dense memories5-6 . Although one dimensional (1D) magnetic systems have been intensely studied theoretically, the experimental determination of the extent and persistence of short- and long-range magnetic interactions, and how these interactions are affected by boundary conditions induced at the end of the chains remain unknown. We report structural and magnetic properties of ultra-short 1D iron chains subject to controlled boundary conditions. These iron chains are grown using iron phthalocyanine (FePc) thin films and FePc/ metal-free-phthalocyanine (H2Pc) superlattices (SLs), in which their length is precisely controlled by the thickness of the deposited FePc layers, and boundary conditions by electronic hybridization at the end of the chains. The electronic hybridization and local bonding environment is observable by element selective X-ray absorption spectroscopy (XAS). Ultra-short 1D iron chains between 7 and 200 atoms long become ferromagnetic below 5 K, and their magnetic response is strongly dependent on the boundary conditions imposed on the end atoms. The coercive field increases with the iron chain length with hybridized boundaries, whereas in chains not subject to hybridization the coercive field remains constant. A quantitative, semi-classical model based on the Dzyaloshinski-Moriya interaction, provides an understanding of these observations, in good agreement with experimental results. Work supported by the National Science Foundation under grants No. 1804414 and 1805585. Prepared by LLNL under Contract DE-AC52-07NA27344.References: 1. S. Datta, B. Das, Appl Phys Lett 56 (7), 665-667 (1990) 2. I, Zutic, J. Fabian, S. Das Sarma, Rev Mod Phys 76 (2), 323-410 (2004) 3. V. A. Dediu, L. E. Hueso, I. Bergenti, C. Taliani, Nat Mater 8 (9), 707-716 (2009) 4. A. J. Leggett, S. Chakravarty, A. T. Dorsey, M. P. A. Fisher, A. Garg, W. Zwerger, Rev Mod Phys 59 (1), 1-85, (1987) 5. Sinitskii, A.; Fursina, A. A.; Kosynkin, D. V.; Higginbotham, A. L.; Natelson, D.; Tour, J. M., Appl Phys Lett 95 (25), 253108 (2009) 6. Sinitskii, A.; Tour, J. M., ACS Nano 3 (9), 2760-2766 (2009)

Twisted Magnetism in Ultra-Short 1D Iron Chains with Hybridized Boundaries

Atomically thin transition metal dichalcogenides (TMD) semiconductors hold enormous potential for modern optoelectronic and ultra-low powered devices. By inducing long-range ferromagnetism (FM) in these semiconductors through the introduction of small amounts of a magnetic dopant, it is possible to extend their potential in emerging spintronic applications [1,2]. Our recent study showed that room temperature magnetism is achieved in V-doped WS2 monolayers [3], while still maintaining its characteristic optical properties. In this work we demonstrate light-mediated, room temperature FM, in V-doped WS2 monolayers. We probe this effect using the principle of magnetic LC resonance [4], which employs a soft ferromagnetic Co-based microwire coil driven near resonance in the radio frequency regime. Combining LC resonance, with an outstanding giant magneto-impedance effect, renders the coil highly sensitive to changes in the magnetic flux through its core. The V-doped WS2 monolayer is placed at the core of the coil where it is excited with a laser, while its magnetic permeability is probed by the coil. We found that the magnetic permeability of the monolayers is dependent on laser intensity, confirming light control of room temperature magnetism in this two-dimension material. Density functional theory calculations lead us to understand that this phenomenon is a consequence of an accumulation of excess holes in the conduction and valence bands, as well as carriers trapped in the magnetic doping states, which in turn mediates the magnetization of V-WS2 monolayers. These findings provide a promising route to exploit light-controlled FM in two-dimensional TMD based spintronic devices.References: [1] Dietl, T. A ten-year perspective on dilute magnetic semiconductors and oxides. Nat. Mater. 9, 965-974 (2010) [2] Dietl, T., Bonanni, A. & Ohno, H. Families of magnetic semiconductors – an overview. Journal of Semiconductors 40, 8 (2019) [3] Zhang, F., et. al. Monolayer Vanadium-doped Tungsten Disulfide: A Room-Temperature Dilute Magnetic Semiconductor. https://arxiv.org/abs/2005.01965 [4] Ortiz Jimenez, V., et. al. A magnetic sensor using a 2D van der Waals ferromagnetic material. Sci. Rep. 10, 4789 (2020)

Light-mediated magnetism in atomically thin vanadium-doped tungsten disulfide semiconductors

Inducing magnetism in graphene has been an important challenge since its discovery. In the dilute regime, magnetic impurities are expected to couple to the Dirac electrons via the Kondo effect in a paramagnetic phase. In the less dilute regime, magnetic impurities in graphene may develop long-range magnetic order mediated by the conduction electrons via the Ruderman-Kittel-Kasuya-Yoshida (RKKY) interaction. Today, the Kondo and RKKY-exchange physics of Dirac electrons in graphene is still elusive while theory predicts competition between a non-trivial Kondo unscreened phase against a RKKY-coupled phase. Considerable experimental efforts have been devoted in this context, with the local magnetic moments originating from carbon vacancies, from adsorption and intercalation (of atoms, clusters or molecules), and from substitutional foreign atoms. Here, we report the incorporation of substitutional manganese (Mn) atoms into graphene as a model case of magnetic doping with transition metals. Ultra-low energy (ULE) ion implantation allows us to precisely tune the kinetic energy of Mn ions, providing control over the form of incorporation and concentration while preserving the structural and electronic properties of graphene [1]. Using low-temperature scanning tunneling microscopy (LT-STM) together with density functional theory (DFT), we identified and characterized point defects that are associated with substitutional-Mn in a carbon single vacancy (Fig.1). These results are complemented by synchrotron-based X-ray photoelectron spectroscopy (XPS), angle-resolved photoemission spectroscopy (ARPES), Raman spectroscopy, X-ray magnetic circular dichroism (XMCD), among others. The new insights provided by our work establish a framework for the controlled incorporation of magnetic dopants in graphene and other 2D materials, using ULE ion implantation.References: [1] P. Willke et al., Appl. Phys. Lett. 105, (2014), 111605

Magnetic doping of graphene with substitutional manganese atoms

Ferromagnetic semiconductors (FMSs) are promising materials for spintronics applications because they are compatible with the highly established semiconductor technology. Although the prototypical FMS (Ga,Mn)As was intensively investigated, it shows low Curie Temperature (TC ≤ 200 K) with only p-type conduction [1]. Recently we have successfully grown Fe-doped III-V FMSs with high TC and both n-type and p-type conduction; p-type (Ga,Fe)Sb (TC = 400 K) [2] and n-type (In,Fe)Sb (TC = 385 K) [3]. In this work, we extend our study to a quaternary-alloy FMS, (In1-x-y,Gax,Fey)Sb. This new FMS allows us to widen the degree of freedom in designing the material properties, including lattice constant, band structure, carrier type and magnetic anisotropy. We investigate the epitaxial growth, transport and magnetic properties of (In1-x-y,Gax,Fey)Sb thin films with different Fe concentration y and Ga concentration x. The sample structure consists of (from top to bottom) InSb (2 nm) / (In1-x-y,Gax,Fey)Sb (15 nm) / AlSb (100 nm) / AlAs (6 nm) / GaAs (100 nm) on a semi-insulating GaAs(001) substrate, grown by low-temperature molecular-beam epitaxy (LT-MBE). Fig.1 shows an X-ray diffraction (XRD) spectrum of the (In0.74,Ga0.1,Fe0.16)Sb sample. The XRD and other characterizations including scanning transmission electron microscopy and magnetic circular dichroism (MCD) indicate that the (In,Ga,Fe)Sb layers grown by LT-MBE maintain the zinc-blende crystal and band structure without any other second phases. Carrier concentrations and TC are estimated from Hall measurements and Arrott plots of the MCD intensity vs. magnetic field (MCD - H) curves, respectively. In (In0.84-x,Gax,Fe0.16)Sb samples (x = 2, 6, 8, 10%), the carrier type can be changed between p-type and n-type by changing x while high TC > 300 K is maintained [Fig.2]. These materials are promising for device applications such as spin diodes and spin transistors. This work was partly supported by Grants-in-Aid for Scientific Research (Nos. 16H02095, 18H05345), the CREST Program (JPMJCR1777) and PRESTO Program (JPMJPR19LB) of JST, and the Spin-RNJ.References: [1] L. Chen et al, Nano Lett., Vol. 11, p.2584 (2011). [2] S. Goel et al, PRB., Vol. 99, p.014431 (2019). [3] N. T. Tu et al, APEX., Vol.12, p.103004 (2019).

Properties of quaternary-alloy ferromagnetic semiconductor (In,Ga,Fe)Sb

Two-dimensional magnetic materials are of great interest for fundamental science and advanced applications while dilute magnetic semiconductors captured worldwide interest by combining magnetism with electronics. MnGaN-2D is an ultimately-thin, 2D-DMS material, consisting of a dense, well-ordered layer of Mn, Ga, and N atoms. MnGaN-2D shows room-temperature ferromagnetism as previously demonstrated with spin-polarized scanning tunneling microscopy as a function of applied magnetic field. This was also predicted by first-principles theoretical calculations which reveal the origins of the ferromagnetism through its highly spin-split and spin-polarized electronic structure.[1] The SP-STM results are recently confirmed by SQUID magnetometry which reveals perpendicular magnetic anisotropy and a high spin-polarization of ∼79% at room temperature.[2] New results for this novel system also suggest the possibility of magneto-elasticity. Theoretical calculations reveal sensitivity of the spin polarization to lattice strain. Spin-orbit coupling is included in the calculations, which indicate either out-of-plane or in-plane anisotropy, dependent on the type of strain whether compressive or tensile. Clear evidence for both compressive and tensile local lattice strains is found by detailed analysis of atomic resolution STM images which reveal a wide, non-Gaussian range of lattice spacings (-18% to + 18% variations), unlike normal materials. Furthermore, scanning tunneling spectroscopy measurements, showing the spin-polarized filled states manganese peak, find fluctuations in the electronic position of the peak from spectrum to spectrum. The FSMP position is also found to fluctuate, depending on lattice strain, in the theoretical calculations, thus indicating a connection between electronic states and magnetic anisotropy in this RT ferromagnetic 2D layer.References: [1] Yingqiao Ma, Abhijit V. Chinchore, Arthur R. Smith, María Andrea Barral, and Valeria Ferrari, A Two-Dimensional Manganese Gallium Nitride Surface Structure Showing Ferromagnetism at Room Temperature, Nano Letters, Vol. 18, p. 158 (2018) [2] Yingqiao Ma, Diego Hunt, Kengyuan Meng, Tyler Erickson, Fengyuan Yang, María Andrea Barral, Valeria Ferrari, and Arthur R. Smith, Local strain-dependent electronic structure and perpendicular magnetic anisotropy of a MnGaN 2D magnetic monolayer, Physical Review Materials, Vol. 4, p. 064006 (2020)

Room-Temperature Ferromagnetism and Strain-dependent Magnetic Anisotropy in 2D MnGaN

Our recent discovery of room-temperature ferromagnetism (FM) in transition metal dichalcogenide (TMD) monolayers of VSe2 has triggered intense research efforts by the scientific community [1,2]. However, the VSe2 monolayers are metallic which may not access the rich electronic and optical phenomena open to semiconductors. In this talk, we present a novel approach to induce long-range FM in TMDs through introducing magnetic dopants to form a dilute magnetic semiconductor. We demonstrate the tunability of room temperature FM in semiconducting TMD monolayers (V-doped WS2 and WSe2) [3,4]. Ferromagnetism peaks at an intermediate vanadium concentration of a few atomic percent (2-4 at.% V) and decreases for higher concentrations, which is consistent with quenching due to orbital hybridization at closer vanadium-vanadium distances. We discover a novel thermally induced spin flipping phenomenon in the V-doped WSe2 monolayers [4], and demonstrate the light-mediated FM in the V-WS2 monolayers at room temperature [5]. These findings pave a new pathway for the development of novel spintronic and valleytronic nanodevices based on atomically thin van der Waals magnetic semiconductors and stimulate further studies in this rapidly expanding research field of 2D magnetism.References: [1] M. Bonilla, M.H. Phan, et al., Strong Room Temperature Ferromagnetism in VSe2 Monolayers on van der Waals substrates, Nature Nanotechnology 13, 289 (2018) [2] V.O. Jimenez, M.H. Phan, et al., A magnetic sensor using a 2D van der Waals ferromagnetic material, Scientific Reports 10, 4789 (2020) [3] F. Zhang, M.H. Phan, et al., Monolayer Vanadium-doped Tungsten Disulfide: An Emerging Room-Temperature Diluted Magnetic Semiconductor, Advanced Science: https://arxiv.org/abs/2005.01965 [4] Y.T.H. Pham, M.H. Phan, et al., Tunable Ferromagnetism and Thermally Induced Spin Flip in Vanadium-doped Tungsten Diselenide Monolayers at Room Temperature, https://arxiv.org/abs/2005.00493 [5] V.O. Jimenez, M.H. Phan, et al., Light-controlled room temperature ferromagnetism in vanadium-doped tungsten diselenide semiconducting monolayers, Nature Communications (submitted).

Premium content

Energy and momentum conservation in spin transfer.

Downloads

Next from MMM 2020

Formation of Spiral Ordering by Magnetic Field in Frustrated Anisotropic Antiferromagnets

Similar lecture

Structural and magnetic properties of Co1.5Ti0.5FeAl Heusler alloy epitaxial thin films

Stay up to date with the latest Underline news!

PRESENTATIONS

CONFERENCES

COMPANY

RESOURCES