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Resistance switching in multilayer structures are typically based on materials possessing ferroic orders. Here we predict an extremely large resistance switching based on the relative spin-orbit splitting in twisted transition metal dichalcogenide (TMD) monolayers tunnel junctions. Because of the valence band spin splitting which depends on the valley index in the Brillouin zone, the perpendicular electronic transport through the junction depends on the relative reciprocal space overlap of the spin-dependent Fermi surfaces of both layers, which can be tuned by twisting one layer. Our quantum transport calculations reveal a switching resistance larger than 10 6 % when the relative alignment of TMDs goes from 0∘ to 60∘ and when the angle is kept fixed at 60∘ and the Fermi level is varied. By creating vacancies, we evaluate how inter-valley scattering affects the efficiency and find that the resistance switching remains large ( 10 4 % ) for typical values of vacancy concentration. Not only should this resistance switching be observed at room temperature due to the large spin splitting, but our results also show how twist angle engineering and control of van der Waals heterostructures could be used for next-generation memory and electronic applications.

We present the result of the localization feature of the quasiperiodic Aubry–André model. Localization and delocalization of energy eigenstates of the system are investigated by taking into account well-known theoretical perspectives such as the fractal dimension and the Landauer formula. Energy spectra of the system are obtained in the form of a Hofstadter butterfly for different values of the incommensurate parameter of the Aubry–André model and different values of the quasiperiodic disordered potentials. The inverse participation ratio analysis and fractal analysis of conductance are used for describing the localization feature of energy eigenstates. The conductance of the eigenstates is also obtained by calculating the transmission eigenvalues in the Landauer picture. [ABSTRACT FROM AUTHOR]

Molecular switches based on functionalized graphene nanoribbons (GNRs) are of great interest in the development of nanoelectronics. In experiment, it was found that a significant difference in the conductance of an anthraquinone derivative can be achieved by altering the pH value of the environment. Building on this, in this work we investigate the underlying mechanism behind this effect and propose a general design principle for a pH based GNR-based switch. The electronic structure of the investigated systems is calculated using density functional theory and the transport properties at the quasi-stationary limit are described using nonequilibrium Green's function and the Landauer formalism. This approach enables the examination of the local and the global transport through the system. The electrons are shown to flow along the edges of the GNRs. The central carbonyl groups allow for tunable transport through control of the oxidation state via the pH environment. Finally, we also test different types of GNRs (zigzag vs. armchair) to determine which platform provides the best transport switchability. [ABSTRACT FROM AUTHOR]

The article titled "Aharonov–Bohm Flux Effects on the Landauer Conductance in Graphene Wormhole" discusses corrections to equations and figures in the original publication. The corrected equations are provided, and the necessary revisions to the text are explained. The authors clarify that the miscalculation does not affect the other results and conclusions presented in the article. The article is authored by Jonathan Acuña Huamaní, Andrés G. Jirón Vicente, Angel E. Obispo, Raul Carita Montero, and Luis B. Castro. [Extracted from the article]

Molecular switches based on functionalized graphene nanoribbons (GNRs) are of great interest in the development of nanoelectronics. In experiment, it was found that a significant difference in the conductance of an anthraquinone derivative can be achieved by altering the pH value of the environment. Building on this, in this work we investigate the underlying mechanism behind this effect and propose a general design principle for a pH based GNR-based switch. The electronic structure of the investigated systems is calculated using density functional theory and the transport properties at the quasi-stationary limit are described using nonequilibrium Green’s function and the Landauer formalism. This approach enables the examination of the local and the global transport through the system. The electrons are shown to flow along the edges of the GNRs. The central carbonyl groups allow for tunable transport through control of the oxidation state via the pH environment. Finally, we also test different types of GNRs (zigzag vs. armchair) to determine which platform provides the best transport switchability.

The theory of the magnetoresistance of the InSb quantum wire is presented. The quantum wire is cylindrical in shape with a symmetric pair of delta-barriers inside. A tunable magnetic field parallel with the axis of the quantum wire is considered. The dependence of the Fermi energy on the magnetic field is calculated. The Landauer formula is used in the calculation of the resistance of a quantum wire. When parameters of the quantum wire (its radius, amplitude of delta-barriers, and distance between them, donor concentration) are appropriately chosen, the theory predicts the dependence of resistance on the magnetic field manifesting well-defined minima. The minima are attributed to the resonant tunnelling of the conduction electrons through the double delta-barrier. [ABSTRACT FROM AUTHOR]

In this work, employing density functional theory based electronic structure calculations, we search for an alternative to MgO as a spacer layer in a magnetic tunneling junction(MTJ), with half-metallic(HM) Co 2 MnSb as an electrode. First, we demonstrate the possibility of designing an all-Heusler alloy based MTJ with semi-conducting(SC) TiCoSb alloy as the spacer material. We probe the robustness of the HM properties of the Mn–Sb/Co interface and show that the HM property is preserved, even with various disorders and defects. The spin-dependent transport behavior indicates that these properties depend sensitively on the heterojunction interfaces and thickness of the spacer material. Further, we study the transport properties of the heterojunctions of Co 2 MnSb alloy with the well-studied insulator MgO as well as the less-explored systems like, NaCl and AlN. In these three insulating materials, the smallest complex band decay coefficient is associated with Δ 1 symmetry, unlike TiCoSb. This feature enables more desirable symmetry-based spin-filtering properties at the Γ point in the 2D Brillouin zone. We further calculate the resistance area (RA) product for all the heterojunctions, important for the realization of highly sensitive magnetic sensors and it is found that the other spacer layers yield a RA product, several orders less in magnitude compared to that of TiCoSb. Our results indicate that NaCl and AlN may be promising as an alternative to MgO as a spacer material. With the chemical compatibilities resulting into minimal interface buckling and an ultra-low RA product, TiCoSb may also be a promising new material for a MTJ with Co 2 MnSb as electrode, specifically in relation to overcoming the variability and current-injection challenges. [Display omitted] • All-Heusler MTJ with electrode Co 2 MnSb and spacer TiCoSb found to be promising. • Half-metallicity at the interface is robust against various disorders and defects. • Thicker layer and Mn-rich interface for TiCoSb show good tunneling properties. • Coherent tunneling observed for MTJs with MgO, NaCl and AlN used as spacer. • All-Heusler MTJ shows ultra-low RA product compared to other spacers. [ABSTRACT FROM AUTHOR]