SCIENCE CHINA Information Sciences, Volume 62 , Issue 12 : 220402(2019) https://doi.org/10.1007/s11432-019-2642-6

The emerging ferroic orderings in two dimensions

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  • ReceivedJul 6, 2019
  • AcceptedSep 10, 2019
  • PublishedNov 13, 2019



This work was supported by National Key RD Program of China (Grant No. 2017YFA0206302), and National Natural Science Foundation of China (Grant Nos. 11504385, 51627801, 61435010, 51702219, 61975134). Han ZHANG and Yupeng ZHANG acknowledge the support from Science and Technology Innovation Commission of Shenzhen (Grant Nos. JCYJ20170818093453105, JCYJ20180305125345378). Teng YANG acknowledges supports from Major Program of Aerospace Advanced Manufacturing Technology Research Foundation NSFC and CASC, China (Grant No. U1537204). Zheng Vitto HAN acknowledges the support from Program of State Key Laboratory of Quantum Optics and Quantum Optics Devices (Grant No. KF201816).


[1] Jiang X T, Liu S X, Liang W Y. Broadband Nonlinear Photonics in Few-Layer MXene Ti3 C2 Tx (T = F, O, or OH). Laser Photonics Rev, 2018, 12: 1700229 CrossRef ADS Google Scholar

[2] Lu L, Liang Z M, Wu L M. Few-layer Bismuthene: Sonochemical Exfoliation, Nonlinear Optics and Applications for Ultrafast Photonics with Enhanced Stability. Laser Photonics Rev, 2018, 12: 1700221 CrossRef ADS Google Scholar

[3] Mu H R, Wang Z T, Yuan J. ACS Photonics, 2015, 2: 832-841 CrossRef Google Scholar

[4] Lu L, Tang X, Cao R. Broadband Nonlinear Optical Response in Few-Layer Antimonene and Antimonene Quantum Dots: A Promising Optical Kerr Media with Enhanced Stability. Adv Opt Mater, 2017, 5: 1700301 CrossRef Google Scholar

[5] Jiang Y Q, Miao L L, Jiang G B. Broadband and enhanced nonlinear optical response of MoS$_{2}$/graphene nanocomposites for ultrafast photonics applications. Sci Rep, 2015, 5: 16372 CrossRef PubMed ADS Google Scholar

[6] Xing C Y, Jing G H, Liang X. Graphene oxide/black phosphorus nanoflake aerogels with robust thermo-stability and significantly enhanced photothermal properties in air.. Nanoscale, 2017, 9: 8096-8101 CrossRef PubMed Google Scholar

[7] Zibouche N, Philipsen P, Kuc A. Transition-metal dichalcogenide bilayers: Switching materials for spintronic and valleytronic applications. Phys Rev B, 2014, 90: 125440 CrossRef ADS arXiv Google Scholar

[8] Xiao D, Liu G B, Feng W. Coupled Spin and Valley Physics in Monolayers of MoS$_{2}$ and Other Group-VI Dichalcogenides. Phys Rev Lett, 2012, 108: 196802 CrossRef PubMed ADS arXiv Google Scholar

[9] Schaibley J R, Yu H, Clark G, et al. Valleytronics in 2D materials. Nat Rev Mater, 2016, 1: 16055. Google Scholar

[10] Sun Z B, Zhao Y T, Li Z B. Small, 2017, 13: 1602896 CrossRef PubMed Google Scholar

[11] Xie H H, Li Z B, Sun Z B. Metabolizable Ultrathin Bi2 Se3 Nanosheets in Imaging-Guided Photothermal Therapy.. Small, 2016, 12: 4136-4145 CrossRef PubMed Google Scholar

[12] Qi J, Lan Y W, Stieg A Z. Piezoelectric effect in chemical vapour deposition-grown atomic-monolayer triangular molybdenum disulfide piezotronics. Nat Commun, 2015, 6: 7430 CrossRef PubMed ADS Google Scholar

[13] Li F, Qi J J, Xu M X. Small, 2017, 13: 1603103 CrossRef PubMed Google Scholar

[14] Ren X H, Zhou J, Qi X. Few-Layer Black Phosphorus Nanosheets as Electrocatalysts for Highly Efficient Oxygen Evolution Reaction. Adv Energy Mater, 2017, 7: 1700396 CrossRef Google Scholar

[15] Wang T, Guo Y L, Wan P B. Flexible Transparent Electronic Gas Sensors.. Small, 2016, 12: 3748-3756 CrossRef PubMed Google Scholar

[16] Xu C, Wang L B, Liu Z B. Large-area high-quality 2D ultrathin Mo$_{2}$C superconducting crystals. Nat Mater, 2015, 14: 1135-1141 CrossRef PubMed ADS Google Scholar

[17] Liu Y, Weiss N O, Duan X. Van der Waals heterostructures and devices. Nat Rev Mater, 2016, 1: 16042 CrossRef ADS Google Scholar

[18] Novoselov K S, Mishchenko A, Carvalho A. 2D materials and van der Waals heterostructures.. Science, 2016, 353: aac9439 CrossRef PubMed Google Scholar

[19] Manzeli S, Ovchinnikov D, Pasquier D. 2D transition metal dichalcogenides. Nat Rev Mater, 2017, 2: 17033 CrossRef ADS Google Scholar

[20] Hu J M, Chen L Q, Nan C W. Multiferroic Heterostructures Integrating Ferroelectric and Magnetic Materials.. Adv Mater, 2016, 28: 15-39 CrossRef PubMed Google Scholar

[21] Gong C, Zhang X. Two-dimensional magnetic crystals and emergent heterostructure devices.. Science, 2019, 363: eaav4450 CrossRef PubMed Google Scholar

[22] Gibertini M, Koperski M, Morpurgo A F. Magnetic 2D materials and heterostructures. Nat Nanotechnol, 2019, 14: 408-419 CrossRef PubMed ADS arXiv Google Scholar

[23] Mermin N D, Wagner H. Absence of Ferromagnetism or Antiferromagnetism in One- or Two-Dimensional Isotropic Heisenberg Models. Phys Rev Lett, 1966, 17: 1133-1136 CrossRef ADS Google Scholar

[24] Stanley H E, Kaplan T A. Possibility of a Phase Transition for the Two-Dimensional Heisenberg Model. Phys Rev Lett, 1966, 17: 913-915 CrossRef ADS Google Scholar

[25] Kosterlitz J M, Thouless D J. Ordering, metastability and phase transitions in two-dimensional systems. J Phys C-Solid State Phys, 1973, 6: 1181-1203 CrossRef ADS Google Scholar

[26] Berezinskii V L. Destruction of long-range order in one-dimensional and two-dimensional systems having a continuous symmetry group I. classical systems. J Exp Theor Phys, 1971, 32: 493. Google Scholar

[27] Fr?hlich J, Lieb E H. Existence of Phase Transitions for Anisotropic Heisenberg Models. Phys Rev Lett, 1977, 38: 440-442 CrossRef ADS Google Scholar

[28] Mohn P. Magnetism in the Solid State: an Introduction. Berlin: Springer, 2005. Google Scholar

[29] Blundell S. Magnetism in Condensed Matter. Oxford: Oxford University Press, 2001. Google Scholar

[30] Huang B, Clark G, Navarro-Moratalla E. Layer-dependent ferromagnetism in a van der Waals crystal down to the monolayer limit. Nature, 2017, 546: 270-273 CrossRef PubMed ADS arXiv Google Scholar

[31] Gong C, Li L, Li Z. Discovery of intrinsic ferromagnetism in two-dimensional van der Waals crystals. Nature, 2017, 546: 265-269 CrossRef PubMed ADS arXiv Google Scholar

[32] Wang Z, Zhang T, Ding M. Electric-field control of magnetism in a few-layered van der Waals ferromagnetic semiconductor. Nat Nanotech, 2018, 13: 554-559 CrossRef PubMed ADS arXiv Google Scholar

[33] Cao Y, Fatemi V, Demir A. Correlated insulator behaviour at half-filling in magic-angle graphene superlattices. Nature, 2018, 556: 80-84 CrossRef PubMed ADS arXiv Google Scholar

[34] Fei Z, Huang B, Malinowski P, et al. Two-dimensional itinerant ferromagnetism in atomically thin Fe$_3$GeTe$_2$. Nat Mater, 2018, 17, 778--782. Google Scholar

[35] Samarth N. Condensed-matter physics: Magnetism in flatland. Nature, 2017, 546: 216-217 CrossRef PubMed ADS Google Scholar

[36] Tsubokawa I. On the magnetic properties of a CrBr$_3$ single crystal. J Phys Soc Jpn, 1960, 15, 1664--1668. Google Scholar

[37] Hansen W N. J Appl Phys, 1959, 30: S304-S305 CrossRef ADS Google Scholar

[38] Starr C, Bitter F, Kaufmann A R. The Magnetic Properties of the Iron Group Anhydrous Chlorides at Low Temperatures. I. Experimental. Phys Rev, 1940, 58: 977-983 CrossRef ADS Google Scholar

[39] Hansen W N, Griffel M. J Chem Phys, 1958, 28: 902-907 CrossRef ADS Google Scholar

[40] Cable J W, Wilkinson M K, Wollan E O. Neutron diffraction investigation of antiferromagnetism in CrCl3. J Phys Chem Solids, 1961, 19: 29-34 CrossRef ADS Google Scholar

[41] McGuire M. Crystal and Magnetic Structures in Layered, Transition Metal Dihalides and Trihalides. Crystals, 2017, 7: 121 CrossRef Google Scholar

[42] Carteaux V, Moussa F, Spiesser M. 2D Ising-Like Ferromagnetic Behaviour for the Lamellar Cr2Si2Te6 Compound: A Neutron Scattering Investigation. Europhys Lett, 1995, 29: 251-256 CrossRef ADS Google Scholar

[43] Ouvrard G, Brec R, Rouxel J. Structural determination of some MPS3 layered phases (M = Mn, Fe, Co, Ni and Cd). Mater Res Bull, 1985, 20: 1181-1189 CrossRef Google Scholar

[44] Taylor B, Steger J, Wold A. Preparation and properties of iron phosphorus triselenide, FePSe3. Inorg Chem, 1974, 13: 2719-2721 CrossRef Google Scholar

[45] Lado J L, Fernández-Rossier J. On the origin of magnetic anisotropy in two dimensional CrI$_{3}$. 2D Mater, 2017, 4: 035002 CrossRef ADS arXiv Google Scholar

[46] Ji H, Stokes R A, Alegria L D. A ferromagnetic insulating substrate for the epitaxial growth of topological insulators. J Appl Phys, 2013, 114: 114907 CrossRef ADS Google Scholar

[47] Brec R. Review on structural and chemical properties of transition metal phosphorus trisulfides MPS$_3$. In: Intercalation in Layered Materials. Boston: Springer, 1986. 148: 93--124. Google Scholar

[48] Wildes A R, Simonet V, Ressouche E. The magnetic properties and structure of the quasi-two-dimensional antiferromagnet CoPS$_{3}$. J Phys-Condens Matter, 2017, 29: 455801 CrossRef PubMed ADS arXiv Google Scholar

[49] Joy P A, Vasudevan S. Magnetism in the layered transition-metal thiophosphates MPS$_{3}$ (M=Mn, Fe, and Ni). Phys Rev B, 1992, 46: 5425-5433 CrossRef PubMed ADS Google Scholar

[50] Kurosawa K, Saito S, Yamaguchi Y. Neutron Diffraction Study on MnPS$_{3}$ and FePS$_{3}$. J Phys Soc Jpn, 1983, 52: 3919-3926 CrossRef ADS Google Scholar

[51] Deng Y J, Yu Y J, Song Y C. Gate-tunable room-temperature ferromagnetism in two-dimensional Fe$_{3}$GeTe$_{2}$. Nature, 2018, 563: 94-99 CrossRef PubMed ADS arXiv Google Scholar

[52] Nozaki H, Umehara M, Ishizawa Y. Magnetic properties of V5S8 single crystals. J Phys Chem Solids, 1978, 39: 851-858 CrossRef ADS Google Scholar

[53] Niu J J, Yan B M, Ji Q Q. Anomalous Hall effect and magnetic orderings in nanothick V$_{5}$S$_{8}$. Phys Rev B, 2017, 96: 075402 CrossRef ADS arXiv Google Scholar

[54] Bonilla M, Kolekar S, Ma Y. Strong room-temperature ferromagnetism in VSe$_{2}$ monolayers on van der Waals substrates. Nat Nanotech, 2018, 13: 289-293 CrossRef PubMed ADS Google Scholar

[55] Gong S J, Gong C, Sun Y Y. Electrically induced 2D half-metallic antiferromagnets and spin field effect transistors. Proc Natl Acad Sci USA, 2018, 115: 8511-8516 CrossRef PubMed ADS Google Scholar

[56] Arai M, Moriya R, Yabuki N. Construction of van der Waals magnetic tunnel junction using ferromagnetic layered dichalcogenide. Appl Phys Lett, 2015, 107: 103107 CrossRef ADS arXiv Google Scholar

[57] Wang X, Tang J, Xia X, et al. Current driven magnetization switching in a van der Waals ferromagnet Fe$_3$GeTe$_2$. 2019,. arXiv Google Scholar

[58] Wang Z, Sapkota D, Taniguchi T. Tunneling Spin Valves Based on Fe3GeTe2/hBN/Fe3GeTe2 van der Waals Heterostructures. Nano Lett, 2018, 18: 4303-4308 CrossRef PubMed ADS arXiv Google Scholar

[59] Handy L L, Gregory N W. Structural Properties of Chromium(III) Iodide and Some Chromium(III) Mixed Halides. J Am Chem Soc, 1952, 74: 891-893 CrossRef Google Scholar

[60] Morosin B, Narath A. X-Ray Diffraction and Nuclear Quadrupole Resonance Studies of Chromium Trichloride. J Chem Phys, 1964, 40: 1958-1967 CrossRef ADS Google Scholar

[61] Huang B, Clark G, Klein D R. Electrical control of 2D magnetism in bilayer CrI$_{3}$. Nat Nanotech, 2018, 13: 544-548 CrossRef PubMed ADS arXiv Google Scholar

[62] Ghazaryan D, Greenaway M T, Wang Z. Magnon-assisted tunnelling in van der Waals heterostructures based on CrBr3. Nat Electron, 2018, 1: 344-349 CrossRef Google Scholar

[63] Zhang W B, Qu Q, Zhu P. Robust intrinsic ferromagnetism and half semiconductivity in stable two-dimensional single-layer chromium trihalides. J Mater Chem C, 2015, 3: 12457-12468 CrossRef Google Scholar

[64] Dillon Jr. J F, Kamimura H, Remeika J P. Magneto-optical properties of ferromagnetic chromium trihalides. J Phys Chem Solids, 1966, 27: 1531-1549 CrossRef ADS Google Scholar

[65] Wang H, Eyert V, Schwingenschl?gl U. Electronic structure and magnetic ordering of the semiconducting chromium trihalides CrCl$_{3}$, CrBr$_{3}$, and CrI$_{3}$. J Phys-Condens Matter, 2011, 23: 116003 CrossRef PubMed ADS Google Scholar

[66] Wang H B, Fan F R, Zhu S S. Doping enhanced ferromagnetism and induced half-metallicity in CrI$_{3}$ monolayer. EPL, 2016, 114: 47001 CrossRef ADS Google Scholar

[67] Sivadas N, Okamoto S, Xu X. Stacking-Dependent Magnetism in Bilayer CrI3. Nano Lett, 2018, 18: 7658-7664 CrossRef PubMed ADS arXiv Google Scholar

[68] Webster L, Yan J A. Strain-tunable magnetic anisotropy in monolayer CrCl$_{3}$, CrBr$_{3}$, and CrI$_{3}$. Phys Rev B, 2018, 98: 144411 CrossRef ADS arXiv Google Scholar

[69] Zheng F W, Zhao J Z, Liu Z. Nanoscale, 2018, 10: 14298-14303 CrossRef PubMed Google Scholar

[70] McGuire M A, Dixit H, Cooper V R. Chem Mater, 2015, 27: 612-620 CrossRef Google Scholar

[71] Song T, Cai X, Tu M W Y. Giant tunneling magnetoresistance in spin-filter van der Waals heterostructures. Science, 2018, 360: 1214-1218 CrossRef PubMed ADS arXiv Google Scholar

[72] Wang Z, Gutiérrez-Lezama I, Ubrig N. Very large tunneling magnetoresistance in layered magnetic semiconductor CrI$_{3}$. Nat Commun, 2018, 9: 2516 CrossRef PubMed ADS arXiv Google Scholar

[73] Klein D R, MacNeill D, Lado J L. Probing magnetism in 2D van der Waals crystalline insulators via electron tunneling. Science, 2018, 360: 1218-1222 CrossRef PubMed ADS arXiv Google Scholar

[74] Jiang S W, Li L Z, Wang Z F. Controlling magnetism in 2D CrI$_{3}$ by electrostatic doping. Nat Nanotech, 2018, 13: 549-553 CrossRef PubMed ADS arXiv Google Scholar

[75] Jiang S W, Shan J, Mak K F. Electric-field switching of two-dimensional van der Waals magnets. Nat Mater, 2018, 17: 406-410 CrossRef PubMed ADS arXiv Google Scholar

[76] Valenzuela S O, Roche S. A barrier to spin filters. Nat Electron, 2018, 1: 328-329 CrossRef Google Scholar

[77] Richter N, Weber D, Martin F. Temperature-dependent magnetic anisotropy in the layered magnetic semiconductors Cr I$_{3}$ and CrB r$_{3}$. Phys Rev Mater, 2018, 2: 024004 CrossRef ADS Google Scholar

[78] Yu X Y, Zhang X, Shi Q. Large magnetocaloric effect in van der Waals crystal CrBr$_{3}$. Front Phys, 2019, 14: 43501 CrossRef ADS Google Scholar

[79] Thompson S E, Parthasarathy S. Moore's law: the future of Si microelectronics. Mater Today, 2006, 9: 20-25 CrossRef Google Scholar

[80] Story T, Ga?a?zka R R, Frankel R B. Carrier-concentration-induced ferromagnetism in PbSnMnTe. Phys Rev Lett, 1986, 56: 777-779 CrossRef PubMed ADS Google Scholar

[81] Ohno H, Chiba D, Matsukura F. Electric-field control of ferromagnetism.. Nature, 2000, 408: 944-946 CrossRef PubMed Google Scholar

[82] Sivadas N, Daniels M W, Swendsen R H. Magnetic ground state of semiconducting transition-metal trichalcogenide monolayers. Phys Rev B, 2015, 91: 235425 CrossRef ADS arXiv Google Scholar

[83] Xing W Y, Chen Y Y, Odenthal P M. Electric field effect in multilayer Cr$_{2}$Ge$_{2}$Te$_{6}$: a ferromagnetic 2D material. 2D Mater, 2017, 4: 024009 CrossRef ADS arXiv Google Scholar

[84] Carteaux V, Brunet D, Ouvrard G. Crystallographic, magnetic and electronic structures of a new layered ferromagnetic compound Cr$_{2}$Ge$_{2}$Te$_{6}$. J Phys-Condens Matter, 1995, 7: 69-87 CrossRef ADS Google Scholar

[85] Zhang X, Zhao Y, Song Q. Magnetic anisotropy of the single-crystalline ferromagnetic insulator Cr$_{2}$Ge$_{2}$Te$_{6}$. Jpn J Appl Phys, 2016, 55: 033001 CrossRef ADS arXiv Google Scholar

[86] Tian Y, Gray M J, Ji H. Magneto-elastic coupling in a potential ferromagnetic 2D atomic crystal. 2D Mater, 2016, 3: 025035 CrossRef ADS arXiv Google Scholar

[87] Dong X J, You J Y, Gu B et al. Strain-induced room-temperature ferromagnetic semiconductors with giant anomalous Hall effect in two-dimensional Cr$_2$Ge$_2$Te$_6$. Preprint at,. arXiv Google Scholar

[88] Wang K Y, Hu T, Jia F H. Magnetic and electronic properties of Cr$_{2}$Ge$_{2}$Te$_{6}$ monolayer by strain and electric-field engineering. Appl Phys Lett, 2019, 114: 092405 CrossRef ADS Google Scholar

[89] Xie L, Guo L, Yu W. Ultrasensitive negative photoresponse in 2D Cr$_{2}$Ge$_{2}$Te$_{6}$ photodetector with light-induced carrier trapping. Nanotechnology, 2018, 29: 464002 CrossRef PubMed ADS Google Scholar

[90] He J J, Ding G Q, Zhong C Y. J Mater Chem C, 2019, 7: 5084-5093 CrossRef Google Scholar

[91] Lohmann M, Su T, Niu B. Probing Magnetism in Insulating Cr2Ge2Te6 by Induced Anomalous Hall Effect in Pt. Nano Lett, 2019, 19: 2397-2403 CrossRef PubMed ADS arXiv Google Scholar

[92] Miao N H, Xu B, Zhu L G. 2D Intrinsic Ferromagnets from van der Waals Antiferromagnets.. J Am Chem Soc, 2018, 140: 2417-2420 CrossRef PubMed Google Scholar

[93] Lan?on D, Ewings R A, Guidi T. Magnetic exchange parameters and anisotropy of the quasi-two-dimensional antiferromagnet NiPS$_{3}$. Phys Rev B, 2018, 98: 134414 CrossRef ADS arXiv Google Scholar

[94] ur Rehman Z, Muhammad Z, Adetunji Moses O. Magnetic Isotropy/Anisotropy in Layered Metal Phosphorous Trichalcogenide MPS? (M = Mn, Fe)Single Crystals.. Micromachines, 2018, 9: 292 CrossRef PubMed Google Scholar

[95] Haines C R S, Coak M J, Wildes A R. Pressure-Induced Electronic and Structural Phase Evolution in the van der Waals Compound FePS$_{3}$. Phys Rev Lett, 2018, 121: 266801 CrossRef PubMed ADS Google Scholar

[96] Kim K, Lim S Y, Lee J U. Suppression of magnetic ordering in XXZ-type antiferromagnetic monolayer NiPS$_{3}$. Nat Commun, 2019, 10: 345 CrossRef PubMed ADS arXiv Google Scholar

[97] Qi J S, Wang H, Chen X F. Two-dimensional multiferroic semiconductors with coexisting ferroelectricity and ferromagnetism. Appl Phys Lett, 2018, 113: 043102 CrossRef ADS arXiv Google Scholar

[98] Cai L, He J, Liu Q. Vacancy-induced ferromagnetism of MoS2 nanosheets.. J Am Chem Soc, 2015, 137: 2622-2627 CrossRef PubMed Google Scholar

[99] Feng S M, Lin Z, Gan X. Doping two-dimensional materials: ultra-sensitive sensors, band gap tuning and ferromagnetic monolayers. Nanoscale Horiz, 2017, 2: 72-80 CrossRef ADS Google Scholar

[100] Cheng Y C, Zhu Z Y, Mi W B. Prediction of two-dimensional diluted magnetic semiconductors: Doped monolayer MoS$_{2}$ systems. Phys Rev B, 2013, 87: 100401 CrossRef ADS Google Scholar

[101] Ramasubramaniam A, Naveh D. Mn-doped monolayer MoS$_2$: An atomically thin dilute magnetic semiconductor. Phys Rev B, 2013, 87: 195201 Mn-doped monolayer MoS$_2$: An atomically thin dilute magnetic semiconductor. Google Scholar

[102] Fan X L, An Y R, Guo W J. Ferromagnetism in Transitional Metal-Doped MoS$_{2}$ Monolayer. Nanoscale Res Lett, 2016, 11: 154 CrossRef PubMed ADS Google Scholar

[103] Xia B R, Guo Q, Gao D Q. High temperature ferromagnetism in Cu-doped MoS$_{2}$ nanosheets. J Phys D-Appl Phys, 2016, 49: 165003 CrossRef ADS Google Scholar

[104] Wang Y, Tseng L T, Murmu P P. Defects engineering induced room temperature ferromagnetism in transition metal doped MoS 2. Mater Des, 2017, 121: 77-84 CrossRef Google Scholar

[105] Li B, Xing T, Zhong M. A two-dimensional Fe-doped SnS$_{2}$ magnetic semiconductor. Nat Commun, 2017, 8: 1958 CrossRef PubMed ADS Google Scholar

[106] Radhakrishnan S, Das D, Samanta A. Fluorinated h-BN as a magnetic semiconductor. Sci Adv, 2017, 3: e1700842 CrossRef PubMed ADS Google Scholar

[107] Jiang P H, Li L, Liao Z L. Spin Direction-Controlled Electronic Band Structure in Two-Dimensional Ferromagnetic CrI3. Nano Lett, 2018, 18: 3844-3849 CrossRef PubMed ADS arXiv Google Scholar

[108] O'Hara D J, Zhu T, Trout A H. Room Temperature Intrinsic Ferromagnetism in Epitaxial Manganese Selenide Films in the Monolayer Limit. Nano Lett, 2018, 18: 3125-3131 CrossRef PubMed ADS arXiv Google Scholar

[109] Mounet N, Gibertini M, Schwaller P. Two-dimensional materials from high-throughput computational exfoliation of experimentally known compounds. Nat Nanotech, 2018, 13: 246-252 CrossRef PubMed ADS Google Scholar

[110] Freitas D C, Weht R, Sulpice A. Ferromagnetism in layered metastable 1T-CrTe$_{2}$. J Phys-Condens Matter, 2015, 27: 176002 CrossRef PubMed ADS Google Scholar

[111] Lin M W, Zhuang H L, Yan J. J Mater Chem C, 2016, 4: 315-322 CrossRef Google Scholar

[112] Kong T, Stolze K, Timmons E I. Adv Mater, 2019, 31: 1808074 CrossRef PubMed Google Scholar

[113] Tong Q J, Liu F, Xiao J. Skyrmions in the Moiré of van der Waals 2D Magnets.. Nano Lett, 2018, 18: 7194-7199 CrossRef PubMed ADS arXiv Google Scholar

[114] Asadi K, de Leeuw D M, de Boer B. Organic non-volatile memories from ferroelectric phase-separated blends. Nat Mater, 2008, 7: 547-550 CrossRef PubMed ADS Google Scholar

[115] Cross L E. Ferroelectric materials for electromechanical transducer applications. Mater Chem Phys, 1996, 43: 108-115 CrossRef Google Scholar

[116] Muralt P. Ferroelectric thin films for micro-sensors and actuators: a review. J Micromech Microeng, 2000, 10: 136-146 CrossRef ADS Google Scholar

[117] Wang Y, Niranjan M K, Janicka K. Ferroelectric dead layer driven by a polar interface. Phys Rev B, 2010, 82: 094114 CrossRef ADS arXiv Google Scholar

[118] Duan C G, Sabirianov R F, Mei W N. Interface Effect on Ferroelectricity at the Nanoscale. Nano Lett, 2006, 6: 483-487 CrossRef PubMed ADS Google Scholar

[119] Jia C L, Nagarajan V, He J Q. Unit-cell scale mapping of ferroelectricity and tetragonality in epitaxial ultrathin ferroelectric films. Nat Mater, 2007, 6: 64-69 CrossRef PubMed ADS Google Scholar

[120] Junquera J, Ghosez P. Critical thickness for ferroelectricity in perovskite ultrathin films. Nature, 2003, 422: 506-509 CrossRef PubMed ADS Google Scholar

[121] Zhang Y, Li G P, Shimada T. Disappearance of ferroelectric critical thickness in epitaxial ultrathin BaZr O$_{3}$ films. Phys Rev B, 2014, 90: 184107 CrossRef ADS Google Scholar

[122] Kooi B J, Noheda B. FERROELECTRICS. Ferroelectric chalcogenides--materials at the edge.. Science, 2016, 353: 221-222 CrossRef PubMed ADS Google Scholar

[123] Chang K, Liu J, Lin H. Discovery of robust in-plane ferroelectricity in atomic-thick SnTe. Science, 2016, 353: 274-278 CrossRef PubMed ADS Google Scholar

[124] Liu K, Lu J, Picozzi S. Intrinsic Origin of Enhancement of Ferroelectricity in SnTe Ultrathin Films. Phys Rev Lett, 2018, 121: 027601 CrossRef PubMed ADS arXiv Google Scholar

[125] Yang C, Liu Y, Tang G. Non-monotonic thickness dependence of Curie temperature and ferroelectricity in two-dimensional SnTe film. Appl Phys Lett, 2018, 113: 082905 CrossRef Google Scholar

[126] Maisonneuve V, Cajipe V B, Simon A. Ferrielectric ordering in lamellar CuInP$_{2}$S$_{6}$. Phys Rev B, 1997, 56: 10860-10868 CrossRef ADS Google Scholar

[127] Vysochanskii Y M, Stephanovich V A, Molnar A A. Raman spectroscopy study of the ferrielectric-paraelectric transition in layered CuInP$_{2}$S$_{6}$. Phys Rev B, 1998, 58: 9119-9124 CrossRef ADS Google Scholar

[128] Belianinov A, He Q, Dziaugys A. CuInP2S6Room Temperature Layered Ferroelectric. Nano Lett, 2015, 15: 3808-3814 CrossRef PubMed ADS Google Scholar

[129] Vasudevan R K, Balke N, Maksymovych P. Ferroelectric or non-ferroelectric: Why so many materials exhibit “ferroelectricity” on the nanoscale. Appl Phys Rev, 2017, 4: 021302 CrossRef ADS arXiv Google Scholar

[130] Liu F, You L, Seyler K L. Room-temperature ferroelectricity in CuInP$_{2}$S$_{6}$ ultrathin flakes. Nat Commun, 2016, 7: 12357 CrossRef PubMed ADS Google Scholar

[131] Si M, Liao P Y, Qiu G. ACS Nano, 2018, 12: 6700-6705 CrossRef Google Scholar

[132] Lee H, Kang D H, Tran L. Indium selenide (In$_2$Se$_3$) thin film for phase-change memory. Mater Sci Eng-B, 2005, 119: 196-201 CrossRef Google Scholar

[133] Han G, Chen Z G, Drennan J. Indium selenides: structural characteristics, synthesis and their thermoelectric performances.. Small, 2014, 10: 2747-2765 CrossRef PubMed Google Scholar

[134] Island J O, Blanter S I, Buscema M. Gate Controlled Photocurrent Generation Mechanisms in High-Gain In$_2$Se$_3$Phototransistors. Nano Lett, 2015, 15: 7853-7858 CrossRef PubMed ADS arXiv Google Scholar

[135] Ding W J, Zhu J B, Wang Z. Prediction of intrinsic two-dimensional ferroelectrics in In$_{2}$Se$_{3}$ and other III$_{2}$-VI$_{3}$ van der Waals materials. Nat Commun, 2017, 8: 14956 CrossRef PubMed ADS Google Scholar

[136] Ye J, Soeda S, Nakamura Y. Crystal Structures and Phase Transformation in In$_{2}$Se$_{3}$ Compound Semiconductor. Jpn J Appl Phys, 1998, 37: 4264-4271 CrossRef ADS Google Scholar

[137] Zhou Y, Wu D, Zhu Y. Nano Lett, 2017, 17: 5508-5513 CrossRef PubMed ADS arXiv Google Scholar

[138] Cui C, Hu W J, Yan X. Intercorrelated In-Plane and Out-of-Plane Ferroelectricity in Ultrathin Two-Dimensional Layered Semiconductor In$_2$Se$_3$. Nano Lett, 2018, 18: 1253-1258 CrossRef PubMed ADS Google Scholar

[139] Xiao J, Zhu H Y, Wang Y. Intrinsic Two-Dimensional Ferroelectricity with Dipole Locking. Phys Rev Lett, 2018, 120: 227601 CrossRef PubMed ADS Google Scholar

[140] Wan S, Li Y, Li W. Adv Funct Mater, 2019, 29: 1808606 CrossRef Google Scholar

[141] Shi Y G, Guo Y F, Wang X. A ferroelectric-like structural transition in a metal. Nat Mater, 2013, 12: 1024-1027 CrossRef PubMed ADS arXiv Google Scholar

[142] Kim T H, Puggioni D, Yuan Y. Polar metals by geometric design. Nature, 2016, 533: 68-72 CrossRef PubMed ADS Google Scholar

[143] Fei Z, Zhao W, Palomaki T A. Ferroelectric switching of a two-dimensional metal. Nature, 2018, 560: 336-339 CrossRef PubMed ADS Google Scholar

[144] Keum D H, Cho S, Kim J H. Bandgap opening in few-layered monoclinic MoTe$_{2}$. Nat Phys, 2015, 11: 482-486 CrossRef ADS Google Scholar

[145] Qi Y, Naumov P G, Ali M N. Superconductivity in Weyl semimetal candidate MoTe$_{2}$. Nat Commun, 2016, 7: 11038 CrossRef PubMed ADS arXiv Google Scholar

[146] Yuan S, Luo X, Chan H L. Room-temperature ferroelectricity in MoTe$_{2}$ down to the atomic monolayer limit. Nat Commun, 2019, 10: 1775 CrossRef PubMed ADS Google Scholar

[147] Shirodkar S N, Waghmare U V. Emergence of Ferroelectricity at a Metal-Semiconductor Transition in a 1T Monolayer of MoS$_{2}$. Phys Rev Lett, 2014, 112: 157601 CrossRef PubMed ADS Google Scholar

[148] Fei R X, Kang W, Yang L. Ferroelectricity and Phase Transitions in Monolayer Group-IV Monochalcogenides. Phys Rev Lett, 2016, 117: 097601 CrossRef PubMed ADS Google Scholar

[149] Wang H, Qian X F. Two-dimensional multiferroics in monolayer group IV monochalcogenides. 2D Mater, 2017, 4: 015042 CrossRef ADS Google Scholar

[150] Hanakata P Z, Carvalho A, Campbell D K. Polarization and valley switching in monolayer group-IV monochalcogenides. Phys Rev B, 2016, 94: 035304 CrossRef ADS arXiv Google Scholar

[151] ?ahin H, Cahangirov S, Topsakal M. Monolayer honeycomb structures of group-IV elements and III-V binary compounds: First-principles calculations. Phys Rev B, 2009, 80: 155453 CrossRef ADS arXiv Google Scholar

[152] Blonsky M N, Zhuang H L, Singh A K. ACS Nano, 2015, 9: 9885-9891 CrossRef Google Scholar

[153] Wu M, Zeng X C. Bismuth Oxychalcogenides: A New Class of Ferroelectric/Ferroelastic Materials with Ultra High Mobility. Nano Lett, 2017, 17: 6309-6314 CrossRef PubMed ADS Google Scholar

[154] Wu J X, Yuan H T, Meng M M. High electron mobility and quantum oscillations in non-encapsulated ultrathin semiconducting Bi$_{2}$O$_{2}$Se. Nat Nanotech, 2017, 12: 530-534 CrossRef PubMed ADS Google Scholar

[155] Yoon S M, Song H J, Choi H C. p-type semiconducting GeSe combs by a vaporization-condensation-recrystallization (VCR) process.. Adv Mater, 2010, 22: 2164-2167 CrossRef PubMed Google Scholar

[156] Mukherjee B, Cai Y, Tan H R. NIR Schottky photodetectors based on individual single-crystalline GeSe nanosheet.. ACS Appl Mater Interfaces, 2013, 5: 9594-9604 CrossRef PubMed Google Scholar

[157] Zhao L D, Lo S H, Zhang Y. Ultralow thermal conductivity and high thermoelectric figure of merit in SnSe crystals. Nature, 2014, 508: 373-377 CrossRef PubMed ADS Google Scholar

[158] Guo T F, Ma Z W, Lin G T, et al. Multiple structure and symmetry types in narrow temperature and magnetic field ranges in two-dimensional Cr$_2$Ge$_2$Te$_6$ crystal,. arXiv Google Scholar

[159] Thiel L, Wang Z, Tschudin M A. Probing magnetism in 2D materials at the nanoscale with single-spin microscopy. Science, 2019, 364: 973-976 CrossRef PubMed ADS arXiv Google Scholar

[160] Cheng R Q, Wang F, Yin L. High-performance, multifunctional devices based on asymmetric van der Waals heterostructures. Nat Electron, 2018, 1: 356-361 CrossRef Google Scholar

[161] Wang F, Wang Z X, Yin L. 2D library beyond graphene and transition metal dichalcogenides: a focus on photodetection.. Chem Soc Rev, 2018, 47: 6296-6341 CrossRef PubMed Google Scholar

  • Figure 1

    (Color online) Different types of magnetic interactions in three-dimensional (3D) crystals.

  • Figure 2

    (Color online) Typical metallic magnetic vdW mateirlas. (a) The magnetic structure of layered V$_5$S$_8$. protectłinebreak (b) Atomic force microscope (AFM is short for antiferromagnetic here in our study) topography of a typical V$_5$S$_8$ flake. (c) Critical temperature $T_{\rm~C}$-thickness $t$ phase diagram. Reproduced from [53]@Copyright 2017 American Physical Society. (d) Schematic structure of layered Fe$_3$GeTe$_2$. (e) Phase diagram of FGT as number of layer and temperature. (f) $R^r_{xy}$ of a four-layer FGT flake under a gate voltage of $V_{\rm~g}$ = 2.1 V. Reproduced from [51]@Copyright 2018 Springer Nature. (g) Schematic structure of layered VSe$_2$. (h) STM images at 150 K. (i) Variations of Ms and Hc with the number of layers of VSe$_2$ film. The inset shows the $M$-$H$ loops for the mono-, bi- and multilayer samples. Reproduced from [54]@Copyright 2018 Springer Nature.

  • Figure 3

    (Color online) Crystal structure of chromium trihalides CrX$_3$. (a) The monoclinic (left panel) and rhombohedral (right panel) phase of CrX$_3$. The red arrows represent the spin direction of Cr atoms. Reproduced from [63]@Copyright 2015 the Royal Society of Chemistry. (b) The magnetic behavior of monolayer, bilayer and trilayer CrI$_3$. Reproduced from [30]@Copyright 2017 Springer Nature. (c) Schematic of magnetic states in bilayer CrI$_3$ and schematic of 2D spin-filter magnetic tunnel junction (sf-MTJ). (d) sf-TMR ratio as a function of bias based on the $\rm~I_t$-V curves in the inset. Reproduced from [70]@Copyright 2017 Science Publishing Group.

  • Figure 4

    (Color online) Controlling magnetism in 2D CrI$_3$ by electrostatic doping. (a) A schematic side view and optical micrograph of a dual-gate bilayer CrI$_3$ field-effect device. (b) MCD versus magnetic field at 4 K at representative gate voltages. (c) Doping density-magnetic field phase diagram at 4 K. Reproduced from [74]@Copyright 2018 Springer Nature.

  • Figure 5

    (Color online) Electrical control of 2D magnetism in bilayer CrI$_3$. (a) Schematic of a dual-gated bilayer CrI$_3$ device fabricated by vdW assembly. (b) RMCD signal of a bilayer CrI$_3$ device as a function of perpendicular magnetic field at zero gate voltage. (c) Intensity of the polar MOKE signal, $\theta~K$, of a non-encapsulated bilayer CrI$_3$ device as a function of both gate voltage and applied magnetic field. (d) RMCD signal of a dual-gated device when sweeping both the graphite top gate and silicon back gate. Gate-dependent MOKE signal of a bilayer CrI$_3$ device prepared in the $\uparrow~\downarrow$ state (e) and in the $\downarrow~\uparrow$ state (f). Reproduced from [61]@Copyright 2018 Springer Nature.

  • Figure 6

    (Color online) Magnon-assisted tunneling in 2D CrBr$_3$ device. (a) Optical microscope image of 2D CrBr$_3$ device. (b) Zero-field differential tunneling conductance $G$ dependence on the gate and bias voltages for the device. protect łinebreak (c) Thickness dependence of the tunneling barrier on the resistivity of the device. (d) Differential tunneling conductance $G$ as a function of $B$. (e) Calculated magnon density of states for $T$ = 10 K, $B$ = 0 T (blue line), $T$ = 10 K, $B$ = 6.25 T (black line), $T~=~T_{\rm~C}$, $B$ = 0 T (red line). (f) Calculated changes of the position of the van Hove singularities in magnon density of states (e) as a function of magnetic field for temperatures close to $T_{\rm~C}$. Reproduced from [62]@Copyright 2018 Springer Nature.

  • Figure 7

    (Color online) Electric-field control of magnetism of 2D semiconducting Cr$_2$Ge$_2$Te$_6$. (a) Schematic of a few-layered Cr$_2$Ge$_2$Te$_6$ flake encapsulated by two h-BN layers, contacted via graphene electrodes. (b) Optical image of the device. (c) Colour map of $I$-$V$ curves as a function of gate voltage at different temperatures. (d) Field effect curves of the device with different $V_{\rm~ds}$ and temperatures. Kerr angle measured at 40 K for negative (e) and positive (f) gate voltages respectively. Reproduced from [32]@Copyright 2018 Springer Nature.

  • Figure 8

    (Color online) Magnetic properties of CrOCl and CrOBr monolayers. (a) Crystal structures of transition-metal oxyhalides. (b) Specific heat CV with respective to temperature for the CrOCl and CrOBr monolayers and the inset shows the corresponding magnetization. Reproduced from [92]@Copyright 2018 American Chemical Society.

  • Figure 9

    (Color online) Layer dependence magnetic properties of NiPS$_3$. (a) Crystal structure of NiPS$_3$. (b) Optical and atomic force microscope image of the sample. (c) Temperature dependences of phonon frequency difference and susceptibility of bulk NiPS$_3$. (d) Thickness dependence of Néel temperature for few-layer NiPS$_3$. Reproduced from [96]@Copyright 2019 Springer Nature.

  • Figure 10

    (Color online) Fe-doped 2D SnS$_2$ magnetic semiconductor. (a) High-resolution scanning transmission electron microscopy (STEM) image of the Fe$_{0.021}$Sn$_{0.979}$S$_2$ flake; the red circles are Fe atoms. (b) Z-contrast mapping in the areas marked with yellow rectangles in (a). Electrical characteristics (c) and photo response (d) of the monolayer Fe$_{0.021}$Sn$_{0.979}$S$_2$ device. Magnetic hysteresis loops for SnS$_2$ (e) and Fe$_{0.021}$Sn$_{0.979}$S$_2$ (f) at 2 K using VSM, respectively. Reproduced from [105]@Copyright 2018 Springer Nature.

  • Figure 11

    (Color online) Schematic view of Zeeman effect and giant magneto band structure effect. (a) External magnetic field induced Zeeman splitting of a specific band. Calculated band splitting using toy model for a 2D system with (b) magnetization along out-of-plane $c$ axis (M//$c$), and (c) rearranged magnetization along in-plane axis (M//$a$) by applying a magnetic field $H$. Reproduced from [107]@Copyright 2018 American Chemical Society.

  • Figure 12

    (Color online) Intrinsic ferromagnetism in 2D MnSe$_x$. (a) Top and side views of MnSe$_2$ lattice. (b) Magnetic hysteresis loop of monolayer MnSe$_x$. Reproduced from [108]@Copyright 2018 American Chemical Society.

  • Figure 13

    (Color online) Data base of 2D easily exfoliatable magnetic materials. (a) The polar histogram of most common 2D structural prototypes include 1036 easily exfoliatable 2D materials. (b) Easily exfoliatable magnetic compounds. Reproduced from [109]@Copyright 2018 Springer Nature.

  • Figure 14

    (Color online) In-plane ferroelectricity in 2D SnTe. (a) Schematics of the SnTe crystal structure (upper) and the SnTe film (lower). (b) Typical STM topography image of SnTe film. The red dotted line indicates the steps of substrate. (c) The stripe domain of a 1-UC SnTe film. The arrow in each domain indicate the direction of lattice distortion. (d) Temperature dependence of the distortion angle for the 1- to 4-UC SnTe films. (e) The d$I$/d$V$ spectra acquired on the surface of a 1-UC film at 4.7 K. The arrows indicate the edges of the valence and conduction bands. The peak at 1.5 V corresponds to a van Hove singularity in the conduction band. (f) Thickness dependence of Sn vacancy density at the growth temperature of 450 K. Reproduced from [122]@Copyright 2016 Science Publishing Group.

  • Figure 15

    (Color online) Crystal structure and the ferroelectric characters of CIPS flakes. The side view (a) and top view (b) for the crystal structure of CIPS with vdW gap between the layers. Within a layer, the Cu, In and P-P form separate triangular networks. Reproduced from [127]@Copyright 1998 American Physical Society. The polarization direction is indicated in by the arrow. AFM topography (c) PFM amplitude (d) and PFM phase (e) for CIPS flakes ranging from 100 to 7 nm thick, on doped Si substrate. Scale bar in (c) is 1 $\mu$m. (f) The PFM amplitude (black) and phase (blue) hysteresis loop for a 4 nm CIPS flake. (g) The $I$-$V$ curves from the Si/CIPS (30 nm)/Au heterostructure. Inset is the schematic of the device. Reproduced from [129]@Copyright 2016 Springer Nature.

  • Figure 16

    (Color online) Crystal structure and the ferroelectric characters of $\alpha$-In$_2$Se$_3$ flakes. (a) Schematic model of IP and OOP switching coupling. (b) and (c) AFM and the corresponding IP PFM images of In$_2$Se$_3$ thin flakes. (d) Schematic model of intercorrelated OOP and IP switching. (e) OOP phase image and (f) the corresponding IP phase image of a 6 nm thick In$_2$Se$_3$ flake acquired immediately after writing two square patterns with a size of 2 and 1 mm by applying $-$7 and +6 V voltages consecutively. The scale bar is 1 mm. (g) $I$-$V$ curves and schematic structure of the planar In$_2$Se$_3$ device. The red and blue solid lines are used to guide the eyes. Reproduced from [135]@Copyright 2017 Springer Nature.

  • Figure 17

    (Color online) Nonvolatile ferroelectric memory effect in 2D $\alpha$-In$_2$Se$_3$. (a) 3D schematic model of the Fe-FET. The Fe-FET is fabricated by vertically stacking grapheme, h-BN, and In$_2$Se$_3$ thin layers in sequence. The white arrows indicate the direction of electric polarization. The zoomed area shows the crystal structure of ferroelectric In$_2$Se$_3$. (b) The hysteresis ferroelectric gating in 2D $\alpha$-In$_2$Se$_3$ based Fe-FET device. The electrical hysteresis loop can be enlarged by the range of the applied top gate voltage. (c) Equivalent capacitor model of the 2D Fe-FET and the corresponding doping level in graphene. A capacitor is used to represent the top ferroelectric gate. The light green slab stands for the insulating h-BN layer. The small color arrows represent the electric dipoles in $\alpha$-In$_2$Se$_3$. Reproduced from [139]@Copyright 2019 WILEY-VCH.

  • Figure 18

    (Color online) Out-of-plane ferroelectricity in $d$1T-MoTe$_2$. (a) PFM phase hysteretic and butterfly loops of monolayer $d$1T-MoTe$_2$. (b) PFM phase image of monolayer $d$1T-MoTe$_2$. (c) Top-view HRTEM image and intensity profile with the atomic structure of $d$1T-MoTe$_2$ placed on top, scale bar, 0.5 nm. (d) Atomic structure image of monolayer $d$1T-MoTe$_2$ and the inset shows atomic structure model (cyan and orange colors represent Mo and Te atoms, respectively), scale-bar, 2 Å (e) Side-view of charge density difference between ferroelectric $d$1T and paraelectric 1T phases (green, purple, cyan, orange, and pink colors denote negative charge, positive charge, Mo atom, Te atom, and polarization, respectively). Reproduced from [146]@Copyright 2019 WILEY-VCH.

  • Figure 19

    (Color online) Ferroelectricity in monolayer group-IV monochalcogenides. (a) The schematic side views of the two distorted degenerate polar structures (B and B$'$) and the high symmetry nonpolar phase (A). (b) The free-energy contour plot of monolayer SnSe according to the tilting angles ($\theta_1$ and $\theta_2$). The phases A, B, and B$'$ are marked. (c) Phase diagram of monolayer SnSe under strain. Reproduced from [148]@Copyright 2016 American Physical Society.

  • Figure 20

    (Color online) Schematic vision of the future applications of two-dimensional materials with ferroic orderings.

  • Table 1   2D magnets categorized according to the types of conventional 3D magnetic interactions shown in Figure
    Model system Indirect exchange
    CrI$_3$ [30,35]
    CrBr$_3$ [36,37]
    CrCl$_3$ [38-41]) Super-exchange/ CrI$_3$ [45]
    Ising Cr$_2$Si$_2$Te$_6$ [42] Double-exchange/ Cr$_2$Ge$_2$Te$_6$ [46]
    FePS$_3$ [43] Ligand
    FePSe$_3$ [44]
    Fe$_3$GeTe$_2$ [51]
    XY NiPS$_3$ [47] RKKY Experimentally missing$^{\rm~a)}$
    CoPS$_3$ [48]
    Cr$_2$Ge$_2$Te$_6$ [31]
    Heisenberg MnPS$_3$ [49] Stoner/Itinerant Fe$_3$GeTe$_2$ [51]
    MnPSe$_3$ [50]


  • Table 2   The magnetic properties of known experimental 2D magnetic materials
    Materials FM/AFM Curie/Neel temperature Gap Ref.
    Fe$_3$GeTe$_2$ family Fe$_3$GeTe$_2$ FM 20 K Metallic [51]
    CrGeTe$_3$ Cr$_2$Ge$_2$Te$_6$ FM 64 K [32]
    family Cr$_2$Si$_2$Te$_6$ FM 80 K 0.4 eV/1.2 eV [111]
    FePS$_3$ AFM 123 K 1.5 eV [94]
    XPS family MnPS$_3$ AFM 78 K 2.4 eV [94]
    NiPS$_3$ AFM 130 K [96]
    Odd-layer CrI$_3$ FM 45 K Semiconducting [30]
    CrI$_3$ family Even-layer CrI$_3$ AFM 45 K Semiconducting [61]
    CrBr$_3$ FM 37 K Semiconducting [74]
    VI$_3$ FM 49 K 0.6 eV [112]
    V$_5$S$_8$ AFM 8 K Metallic [53]
    VSe$_2$ FM 300 K Metallic [54]
    Others Fe-SnS$_2$ FM 31 K 2.2 eV [105]
    Fluorinated h-BN FM Semiconducting [106]
    MnSe$_x$ FM 300 K Semiconducting [108]
    1T-CrTe$_2$ FM 310 K Metallic [110]