In-situ Formation of Superconducting FeTe/layered-MnTe heterostructures

Abstract

Manganese telluride (MnTe) has garnered strong interest recently for its antiferromagnetic semiconductor properties, which are promising for applications in spintronics, data storage, and quantum computing. In this study, we discovered that the deposition of FeTe onto zinc-blende MnTe (ZB-MnTe) via molecular beam epitaxy (MBE) results in a phase transition from ZB-MnTe to a layered MnTe (l-MnTe) phase with van der Waals (vdW) gaps, which is a novel phase of MnTe. The l-MnTe phase was characterized using cross-sectional high-angle annular dark-field (HAADF) imaging, energy-dispersive X-ray spectroscopy (EDS) mapping, and X-ray photoelectron spectroscopy (XPS). The FeTe/l-MnTe heterostructure exhibits high-quality superconducting properties that closely resemble those of bulk superconducting materials. We found that the Fe:Te ratio during FeTe deposition is critical to the phase transition and the superconducting characteristics of the heterostructure system. An increased Fe:Te ratio used for the FeTe growth leads to localized formation of layered Mn4Te3 (l-Mn4Te3) and degrades the superconductivity, while a decreased ratio may hamper the transformation from ZB-MnTe to l-MnTe, leading to the loss of superconductivity. Most importantly, this study reports the realization of a layered structure of MnTe by an in-situ approach via chemical interaction, which might be further applied to generating unprecedented phases of materials under certain conditions.

Locations

• arXiv (Cornell University) - View - PDF