The atlas of ferroicity in two-dimensional MGeX3 family: Room-temperature ferromagnetic half metals and unexpected ferroelectricity and ferroelasticity

Calculated magnetic exchange interactions in the van der Waals layered magnet CrSBr

“…Since the discovery of intrinsic ferromagnetic order in atom thin CrI 3 [1], Cr 2 Ge 2 Te 6 [2] and Fe 3 GeTe 2 [3], two-dimensional (2D) ferromagnetic materials have attracted great attention due to their novel physical properties and potential applications in spintronics. Therefore, a great deal of theoretical efforts have been devoted to predicting intrinsic 2D ferromagnetic monolayers with relatively high Curie temperature (T C ), including transition metal halides (MX 3 /MX 2 , X = Cl/Br/I) [4][5][6][7], transition metal dichalcogenides (MX 2 , X = O/S/Se/Te) [8][9][10][11], ternary transition metal compounds (ABX 3 ) [12][13][14][15][16][17], etc. Although there is a wide variety of potential 2D ferromagnets from theoretical predictions, making these ultra-thin 2D ferromagnets in laboratory is difficult [18].…”

Intrinsic Multiferroic in VNI Monolayer

“…A buckled CrN monolayer is a ferromagnetic and ferroelectric multiferroic metal in which the out-of-plane polarization is stabilized by spin–phonon coupling and metal–metal interaction . Theoretically, 2D CuCrX 2 (X = S, Se), double-metal-trihalide monolayers, ReWCl 6 , VOF, MGeX 3 (M = metal element; X = O/S/Se/Te), and 2D bimetal phosphates, i.e., M I M II P 2 X 6 (M I , M II = different metal elements; X = O/S/Se/Te), have also been predicted as 2D multiferroics.…”

Tailoring interlayer magnetic coupling to modify the magnetic properties of FeCl2 bilayers by self-intercalation

“…49,50 All the band gaps of majority spin channels in the intercalated system are larger than 1.75 eV, and even reach 3.69 eV for the 11% Fe-intercalated FeCl 2 bilayer, which are larger than in the reports of 2D halfmetal materials, such as CoGa 2 X 4 (X = S, Se and Te) and MnGeX 3 (X = Se and Te). 51,52 The large gap of majority spin channels can effectively prevent spin leakage. The electronic states near the Fermi level of both the FeCl 2 bilayer and its intercalated systems mainly stem from Fe-d orbitals.…”