Controlling Ferromagnetic Easy Axis in a LayeredMoS2Single Crystal

Abstract

We report the effective methods to induce weak ferromagnetism in pristine MoS2 persisting up to room temperature with the improved transport property, which would lead to new spintronics devices. The hydrogenation of MoS2 by heating at 300 °C for 1 h leads to the easy axis out of plane, while the irradiation of proton with a dose of 1 × 10(13) P/cm(2) leads to the easy axis in plane. The theoretical modeling supports such magnetic easy axes.

Hydrogenation-induced atomic stripes on the2H−MoS2surface

“…It is notable that an existence of carbon after the H 2 annealing implies that a formation of the hydrocarbon (C-H bonds) [28] was inevitable during the hydrogenation at the condition of Fig. 1(c) [18].…”

“…This finding motivates one to investigate the interaction between hydrogen and the MoS 2 surface based on a combination of the transmission electron microscopy (TEM), scanning photoelectron microscopy (SPEM), angleresolved photoelectron spectroscopy (ARPES), and firstprinciples calculation. Further, we indicate that the electronic states associated with the emerging phase appear near the Fermi level (E F ) and reduce the band gap, promising in vanishing the Schottky barrier.For the hydrogenation, natural single crystalline MoS 2 flakes were annealed at 300• C for 1 h in the hydrogen gas ambient [18]. And then, for the structural characterization, the hydrogenated samples were measured by using TEM with an energy of electron beam (200 keV), which is strong enough to knock out a large number of S atoms [20,21].…”

“…• C for 1 h in the hydrogen gas ambient [18]. And then, for the structural characterization, the hydrogenated samples were measured by using TEM with an energy of electron beam (200 keV), which is strong enough to knock out a large number of S atoms [20,21].…”

“…Further, a novel fabrication using the electron-beam-based techniques produced the semiconducting MoS 2 nanoribbons [16] and metallic nanowires [17]. In a separate method, it is notable that the hydrogenation of MoS 2 single crystal has induced a weak ferromagnetism with the improved transport property at room temperature [18]. Recently, the nanoroad prepared by the controlled (i.e., stripe-patterned) hydrogenation on the MoS 2 monolayer has been theoretically shown to be metallic [19].…”

Unexpected large room-temperature ferromagnetism in porous Cu2O thin films

“…There has recently been tremendous interest in understanding the origin of room temperature unconventional ferromagnetism observed in a variety of materials that are nonmagnetic in their bulk forms [1][2][3]. Over the last decade, many groups have focused on doped, transition or rare earth, compound semiconductors such as Co:TiO 2 [4], Co:ZnO [5], Li:SnO 2 [6], and Cr:In 2 O 3 [7] due to their prospective applications in spintronic devices.…”