Search arXivSearch

arXiv · 2504.15614

Spin-dependent electronic transport in NiMnSb/MoS2(001)/NiMnSb magnetic tunnel junction

Abstract

Half-metallic Heusler alloy compounds with Curie temperatures above room temperature are suitable candidate electrode materials for injecting large spin-polarised charge carriers into the semiconducting barriers at the ferromagnet semiconductor junction to obtain highly spin-polarised current. Combining the density functional theory and non-equilibrium Green's function method, the electronic structure, spin dependent electron transport in NiMnSb/MoS2(001)/NiMnSb is studied. The possibilities of injecting 100% spin-polarised electron into MoS2 using half metallic NiMnSb as an electrode, the layer dependent, and the effect of the type of interface on electronic structure and spin-transport properties in magnetic tunnel junction devices are studied. We show that the half-metallicity of NiMnSb(111) is preserved at the interface between the half-Heusler alloy NiMnSb and MoS2. NiMnSb keeps a fully spin-polarised state in the majority spin channel at the interface between NiMnSb and MoS2, injecting fully spin-polarised electrons into the semiconductor. The device based on NiMnSb/MoS2(single layer)/NiMnSb has a metallic interface. Metal-induced states in the spin-majority channel of MoS2 are seen after making an interface with half metallic NiMnSb. In contrast, the NiMnSb/MoS2(three layers)/NiMnSb interface with a multilayer of MoS2 has a band gap region, and electrons can tunnel through the junction. The Mn-S interface is more conducting than the Sb-S interface due to the strong bonding of Mn and S atoms at the Mn-S interface.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Aloka Ranjan Sahoo, Sharat Chandra. 2025-04-22. Spin-dependent electronic transport in NiMnSb/MoS2(001)/NiMnSb magnetic tunnel junction. https://arxiv.org/abs/2504.15614

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Incommensurate structural and magnetic modulations in potassium-rich cryptomelane, K$_x$Mn$_8$O$_{16}$ ($x\approx1.45$)

Cryptomelane is a hollandite-like material consisting of K$^+$ cations in an $α$-MnO$_2$ tunnel-like crystallographic motif. Cryptomelane with stoichiometry K$_x$Mn$_8$O$_{16}$ ($x\approx1.45$) has been synthesized and its magnetic properties investigated using variable-temperature magnetic susceptibility, heat capacity, and neutron powder diffraction. Three distinct transitions at $T_1=184$\,K, $T_2=54.5$\,K, and $T_3=24$\,K are observed. At $T_1$ there is a subtle tetragonal$\rightarrow$monoclinic transition associated with emergence of a set of non-magnetic superstructure peaks indexable to a $\vec{k}_\mathrm{struc}\approx0.74\vec{c^*}$ incommensurate modulation parallel to the $α$-MnO$_2$ tunnels. Our findings are consistent with a relation previously reported in titanate hollandites, that $x\approx2|\vec{k}_\mathrm{struc}|$. Magnetic Bragg peaks emerge below $T_2=54.5$\,K, and their positions indicate an incommensurate modulated magnetic structure. The model consistent with the data is a dual-$\vec{k}_\mathrm{mag}$ structure with a ferromagnetic $|\vec{k}_\mathrm{mag}|=0$ component and an incommensurate $\vec{k}_\mathrm{mag}\approx0.37\vec{c^*}$, with the latter most likely to be helical. The period of oscillation of the incommensurate magnetic component is in line with predictions based on a Heisenberg spin Hamiltonian [Mandal \textit{et al}. Phys. Rev. B 90, 104420 (2014)]. Below $T_3=24$\,K, there is a magnetic transition, which gives rise to a different set of magnetic Bragg peaks indicative of a highly complex magnetic structure.

cond-mat.mtrl-sci

An anisotropic functional for two-dimensional material systems

Density function theory is the workhorse of modern electronic structure theory. However, its accuracy in practical calculations is limited by the choice of the exchange-correlation potential. In this respect, two-dimensional materials pose a special challenge, as all these materials and their heterostructures have a crucial similarity. The underlying atomic structures are strongly spatially inhomogeneous, implying that current exchange-correlation functionals, that in almost all cases are isotropic, are ill-prepared for an accurate description. We present an anisotropic screened-exchange potential, that remedies this problem and reproduces the band-gap of 2D materials as well as the piecewise linearity of the total energy with fractional occupation number.

cond-mat.mtrl-sci

Thermally-driven reorientation of the Néel vector in altermagnetic MnTe

Altermagnets are novel magnetic systems that possess a spin-polarized electronic band structure without a net magnetic moment, making them promising for device applications. Hexagonal MnTe, a prototypical altermagnet, arguably exhibits the most properties consistent with theoretical predictions, including an anomalous Hall effect despite a vanishing net magnetization, and altermagnetinduced electronic band splitting. However, fundamental questions remain, including why some effects only appear significantly below the magnetic ordering temperature. Here, we resolve this discrepancy by revealing a reorientation of the Néel vector in single-crystalline MnTe. The Néel vector points 30° from the a-axis at low $T$, before aligning directly with the a-axis around $T\simeq 260$ K. We attribute this to single-ion anisotropy, which depends on temperature-dependent lattice parameters. We obtained these results using muon-spin spectroscopy, magnetization measurements, and X-ray diffraction; we show that the findings are consistent with neutron diffraction. Manipulating this effect, for example through strain, could unlock sensitive electronic detection schemes for external stimuli, paving the way for functional altermagnetic devices.

cond-mat.mtrl-sci