Controlled growth of ultrathin ferromagnetic β‐MnSe semiconductor

Abstract

Two-dimensional (2D) magnetic crystals with intrinsic ferromagnetism are highly desirable for novel spin-electronic devices. However, the controllable synthesis of 2D magnets, especially the direct growth of 2D magnets on substrate surfaces, is still a challenge. Here, we demonstrate the synthesis of ultrathin zinc-blende phase manganese selenide (β-MnSe) nanosheets using the chemical vapor deposition (CVD) technique. The 2D β-MnSe crystals exhibit distinct ferromagnetic properties with a Curie temperature of 42.3 K. Density functional theory (DFT) calculations suggest that the ferromagnetic order in β-MnSe originates from the exchange coupling between the unsaturated Se and Mn atoms. This study presents significant progress in the CVD growth of ultrathin 2D magnetic materials by thinning bulk magnets, and it will pave the way for the building of energy-efficient spintronic devices in the future.

Room-temperature electric field control of spin filtering efficiency for enhanced modulation of optical spin polarization in a defect-functional 0D–2D hybrid nanostructure

“…Finally, we discuss the applicability of such a spin-filtering system to two-dimensional materials, which are the promising candidates for future opto-electronic and spintronic devices. 37 For transition metal dichalcogenides (TMDCs) such as MoS 2 38 and WS 2 , 39 spin polarization of the optically excited carries higher than 60% has been observed at RT via circularly polarized PL spectroscopy. It has recently been reported in these materials that deep-level defects can be introduced in the band gap.…”

Synthesis Methods and Property Control of Two-Dimensional Magnetic Materials

“…3(b) and 3(c). [39,40] Here, 𝛽-MnSe nanosheets exhibited distinctive ferromagnetism with Curie temperature of only 42.3 K. On the other hand, 𝛼-MnTe is a room-temperature antiferromagnetic, direct-band-gap p-type semiconductor, possessing a unique band structure. Yuan et al reported the growth of highly stable ultra-thin 𝜀-phase iron oxide crystals in ambient air.…”

“…Consequently, researchers have turned to the CVD method for epitaxial growth of materials such as MnSe, MnTe, Cr5Te8, and Cr2S3 on mica or sapphire substrates. [22,[39][40][41] In comparison to molecular beam epitaxy, which suffers from drawbacks such as expensive equipment, complex procedures, and low growth efficiency, CVD offers a more straightforward and practical approach. Te atoms in the film.…”

Synthesis and optical properties of MnSe nanostructures: A review

“…However, higher flow rate of H 2 leads to increase of the diffusion rate of Mn and Se providing sufficient precursor to create more complicated structure. In addition, during the formation of complex structure in rich H 2 environment, Mn terminated edge growth becomes more energetically favorable [57].…”