Distinct ferrovalley characteristics of the Janus RuClX (X = F, Br) monolayer

Abstract

Different ferrovalley characteristics were observed in the valence band and conduction band of RuClF and RuClBr monolayers, respectively.

Piezoelectricity and valley polarization in a semilithiated 2H-TiTe2 monolayer with near room-temperature ferromagnetism

“…Therefore, the energy degeneracy between the − K and + K valleys is removed so that the valley polarized state is realized in the conduction band of Li@2H-TiTe 2 rather than in the frequently reported valence band of other ferrovalley materials. Remarkably, the valley polarization with a fully clean energy window reaches as sizable as 160 meV, which is larger than or comparable to that reported in monolayers VSe 2 (78.2 meV), 11 FeClBr (188 meV), 14 LaH 2 (137 meV), 15 Cr 2 COF MXene (291/379 meV), 16 CeI 2 (208 meV), 17 2H-RuCl 2 (240 meV), 18 CrHfN 2 Cl 2 (55 meV), 19 RuClX (X = F, Br) (194/226 meV), 20 Fe(OH) 2 (67 meV), 21 VSSe (85 meV), 29 and VClBr (70 meV). 30 It is noteworthy that the valley polarization of the conduction band will be reversed when the magnetization points to the − z direction, as shown in Fig.…”

“…Up to date, 2D ferrovalley semiconductors with the clean valley states and considerable valley polarization for room-temperature operation are extremely rare and yet to be verified experimentally. 14–21 It is therefore meaningful to accelerate the discovery of such ferrovalley materials for designing valley-based electronic and optoelectronic devices.…”

Two dimensional Janus RuXY (X, Y = Br, Cl, F, I, X ≠ Y) monolayers: ferromagnetic semiconductors with spontaneous valley polarization and tunable magnetic anisotropy

“…The property regulations of the three Janus RuXY monolayers with ferrovalley properties at different biaxial strains were considered also considered in this work, which was different from the previous studies. 32,51 The properties of RuBrCl, RuBrF, and RuClF monolayers could be modulated by considering the biaxial strains. 58,59 In Fig.…”

“…50 The valley splitting energies of the RuBrCl and RuClF monolayers were similar to the values given in a previous report. 51 The ferrovalley materials with large valley splitting will overcome thermal noise and can be applied in logic devices. In addition, the stability of RuIBr, RuBrCl, RuBrF and RuClF monolayers was evaluated using phonon dispersion.…”

Magnetic and Ferroelectric Manipulation of Valley Physics in Janus Piezoelectric Materials

“…8−15 Generally, due to the inherent magnetic exchange interaction and spatial inversion symmetry breaking, the valley polarization (VP) is spontaneously introduced in 2D ferromagnetic systems after considering spin−orbit coupling (SOC). 16,17 Valley polarization is prone to occur in several 2D single-layer materials, such as the magnetic VSe 2 , 16 VSSe, 18 AuCl 3 , 19 CeI 2 , 20 RuCl 2 , 21 RuClX (X = F, Br), 22 VSi 2 P 4 23,24 and VGe 2 P 4 monolayers. 25 It is noteworthy that there is very little research on whether the VP generates in 2D multilayer materials.…”