Robust Low-Bias Negative Differential Resistance in Graphene Superlattices

TL;DR

This paper demonstrates how engineering parameters in graphene superlattices can produce multipeak negative differential resistance with high PVR at low bias, promising for advanced nanoelectronic applications.

Contribution

It introduces a novel method to control NDR in graphene superlattices via Fermi velocity engineering and detailed parameter analysis.

Findings

Achieved multipeak NDR with PVR up to 167.

Demonstrated control of NDR through Fermi velocity modulation.

Identified potential for low-power, high-speed nanoelectronic devices.

Abstract

Here, we present a detailed study on low bias current-voltage (I-V) characteristic of graphene superlattice (GSL) resonant tunneling diode (RTD) with heterostructured substrate and series of grounded metallic planes placed over graphene sheet which induce periodically modulated Dirac gap and Fermi velocity barrier. We investigate the effect of GSL parameters on I-V characteristics within the Landauer-Buttiker formalism and adopted transfer matrix method. We show how the engineering these parameters results in multipeak NDR in proposed device. Moreover we provide a novel venue to control the NDR in GSL with Fermi velocity engineering. From this viewpoint we obtain multipeak NDR through miniband align in GSL. Maximum Pick to Valley ratio (PVR) up to 167 obtained for correlation velocity of 1.9 and bias voltages between 70-130 mV. Our finding in low bias regime and high PVR multipeak NDR have a considerable importance in multi-valued memory functional circuit, low power and high-speed nanoelectronic devices application.