Multifunctional steep-slope spintronic transistors with spin-gapless-semiconductor or spin-gapped-metal electrodes

Abstract

Spin-gapless semiconductors (SGSs) are a promising class of materials for spintronic applications, enabling functions beyond conventional electronics. This study introduces a novel design for multifunctional spintronic field-effect transistors (FETs) using SGSs and/or spin-gapped metals (SGMs) as source and drain electrodes. These devices operate similarly to metal-semiconductor Schottky barrier FETs, where a potential barrier forms between the SGS (or SGM) electrode and the semiconducting channel. Unlike traditional Schottky barrier FETs, these devices utilize the unique spin-dependent transport properties of SGS/SGM electrodes to achieve sub-60 mV/dec switching, overcoming the 60 mV/dec sub-threshold swing limit in MOSFETs for low-voltage operation. Additionally, SGMs contribute a negative differential resistance (NDR) effect with an ultra-high peak-to-valley current ratio. The proposed spintronic FETs combine sub-60 mV/dec switching, non-local giant magnetoresistance (GMR), and NDR, making them suitable for applications like logic-in-memory computing and multivalued logic. These properties support computing architectures beyond the von-Neumann model, enabling efficient data processing. Two-dimensional (2D) nanomaterials provide a promising platform for these multifunctional FETs. We screen a computational 2D materials database to identify suitable SGS and SGM materials, selecting VS$2$ as the SGS for simulations. Using a non-equilibrium Green's function method with density functional theory, we simulate transfer ($I\mathrm{D}$-$V_{\mathrm{G}}$) and output ($I_{\mathrm{D}}$-$V_{\mathrm{D}}$) characteristics of a VS${}_2$/Ga${}_2$O${}_2$ FET based on 2D type-II SGS VS${}_2$, predicting a sub-threshold swing of 20 mV/dec, a high on/off ratio of 10${}^8$, and a notable non-local GMR effect, demonstrating potential for low-power, high-performance applications.

final version including adapted supplemental material

References in corpus (17)

• The PseudoDojo: Training and grading a 85 element optimized norm-conserving pseudopotential table
• QuantumATK: An integrated platform of electronic and atomic-scale modelling tools
• The Computational 2D Materials Database: High-Throughput Modeling and Discovery of Atomically Thin Crystals
• Exceptional piezoelectricity, high thermal conductivity and stiffness and promising photocatalysis in two-dimensional MoSi2N4 family confirmed by first-principles
• Recent Progress of the Computational 2D Materials Database (C2DB)
• Realization of spin gapless semiconductors: the Heusler compound Mn2CoAl
• Structure-driven intercalated architecture of septuple-atomic-layer $M{A}_2{Z}_4$ family with diverse properties from semiconductor to topological insulator to Ising superconductor
• First-principles Green's-function method for surface calculations: a pseudopotential localized basis set approach
• A New Spin Gapless Semiconductors Family: Quaternary Heusler Compounds
• Large current modulation in exfoliated-graphene/MoS2/metal vertical heterostructures
• High throughput screening for spin-gapless semiconductors in quaternary Heusler compounds
• Ferromagnetism in 2D Vanadium Diselenide
• Ab-initio NEGF Perspective of Ultra-Scaled CMOS: From 2D-material Fundamentals to Novel Dynamically-Doped Transistors
• Sub-60 mV/decade switching with a cold metal as the injection source
• Half-Metal Spin-Gapless Semiconductor Junctions as a Route to the Ideal Diode
• Ab initio design of quaternary Heusler compounds for reconfigurable magnetic tunnel diodes and transistors
• Spin gapped metals: A novel class of materials for multifunctional spintronic devices