Our study aims to provide a theoretical paradigm for a Λ-type negative differential resistance (NDR) device and to discover the general properties and mechanisms. In this study, we construct a NDR device named a metal-insulator interface reflecting electronic grid, which is made from rutile-$\mathrm{Ru}{\mathrm{O}}_2$ and $\mathrm{Ti}{\mathrm{O}}_2$, and the central region including an extension region with $\mathrm{Ru}{\mathrm{O}}_2\text{−}\mathrm{Ti}{\mathrm{O}}_2$ and a scattering region with pure $\mathrm{Ru}{\mathrm{O}}_2$. The device exhibits a Λ-type NDR phenomenon, which is robust in different crystallographic geometries for both nonmagnetic and altermagnetic ordering for $\mathrm{Ru}{\mathrm{O}}_2$. The NDR phenomenon also shows anisotropy for different magnetic states for $\mathrm{Ru}{\mathrm{O}}_2$, which can be used to distinguish the magnetic ground state of $\mathrm{Ru}{\mathrm{O}}_2$. To explain the Λ-type NDR phenomenon, we propose a general transmission channel selection mechanism in the interface of $\mathrm{Ru}{\mathrm{O}}_2$ and $\mathrm{Ti}{\mathrm{O}}_2$, which can be described by Bragg's law, and we believe that this mechanism is the main source of Λ-type NDR. This effect occurs at the interface, so it has the opportunity to exist in other devices with similar configurations. Our designed NDR device has a broad application in high-frequency oscillators and memory devices.

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• Devices
• Interfaces
• Density functional theory
• Nonequilibrium Green's function