Non-volatile reconfigurable spin logic functions in a two-channel Hall bar by spin-orbit torque-based magnetic domains and directional read current.

A long-standing goal of CMOS-based logic devices is to meet the needs of key markets, including ultralow-power operation and high operation speed, along with the continuing miniaturization of the architecture. However, despite significant progress in their development, conventional CMOS-based devices still suffer from drawbacks such as introducing large unintended leakage currents and volatile behavior. Thus, reconfigurable logic gates based on magnetic domain (MD) have emerged as a highly promising option because they offer fast operation speeds, nonvolatility, and diverse logic functions in a single-device configuration. Here, we address multiple reconfigurable MD logic gates in a single two-channel Hall bar device by varying the voltage-driven read-current directions and selecting a non-inverting or inverting comparator in W/CoFeB/MgO/Ta stacks. The non-volatile MD switching behavior induced by spin-orbit torque significantly affects our logic gate functions, which are not necessarily synchronized to a single clock. By adapting MD switching by spin-orbit torque and anomalous Hall effect voltage outputs, we identified eight reconfigurable logic gates, including AND, NAND, NOR, OR, INH, Converse INH, Converse IMP, and IMP, in a single device. These experimental findings represent a significant step forward in a wide range of MD-based logic applications in the near future.

Bidirectional-nonlinear threshold switching behaviors and thermally robust stability of ZnTe selectors by nitrogen annealing.

Three-dimensional stackable memory frames involving the integration of two-terminal scalable crossbar arrays are expected to meet the demand for high-density memory storage, fast switching speed, and ultra-low power operation. However, two-terminal crossbar arrays introduce an unintended sneak path, which inevitably requires bidirectional nonlinear selectors. In this study, the advanced threshold switching (TS) features of ZnTe chalcogenide material-based selectors provide bidirectional threshold switching behavior, nonlinearity of 104, switching speed of less than 100 ns, and switching endurance of more than 107. In addition, thermally robust ZnTe selectors (up to 400 â„ƒ) can be obtained through the use of nitrogen-annealing treatment. This process can prevent possible phase separation phenomena observed in generic chalcogenide materials during thermal annealing which occurs even at a low temperature of 250 â„ƒ. The possible characteristics of the electrically and thermally advanced TS nature are described by diverse structural and electrical analyses through the Poole-Frankel conduction model.

Role of fluorine in two-dimensional dichalcogenide of SnSe 2.

Authors report an effect of F substitution on layered SnSe2 through the successful synthesis of polycrystalline SnSe2-δF x (0.000 ≤ x ≤ 0.010) by solid-state reaction. Accompanied with density functional theory calculations, the blue shift of A1g peak in Raman spectra reveal that F- ions are substituted at Se vacancy sites as decreasing the reduced mass of vibrational mode associated with Sn-Se bonding. From the measurements of electrical parameters, conductivity as well as carrier concentration are governed by thermally activated behavior, while such behavior is suppressed in Hall mobility, which occurs as F ratio increases. Based on Arrhenius relation, it is found that the potential barrier height at the grain boundary is suppressed with increasing F amount, suggesting that the F- ion is a promising candidate for the grain boundary passivation in the two-dimensional dichalcogenide system.