Inter-Layer Screening Length to Electric Field in Thin Graphite Film

TL;DR

This study investigates how electric fields influence carrier induction in thin graphite films using dual gating, revealing a thickness-dependent screening effect with an experimentally determined screening length of 1.2 nm.

Contribution

The paper introduces the concept of inter-layer screening length in thin graphite, providing experimental measurement and analysis of its impact on electric field-induced conduction.

Findings

Screening length of 1.2 nm experimentally determined

Gate voltage shifts depend on graphite thickness

Inter-layer screening affects electric field penetration

Abstract

Electric conduction in thin graphite film was tuned by two gate electrodes to clarify how the gate electric field induces electric carriers in thin graphite. The graphite was sandwiched between two gate electrodes arranged in a top and bottom gate configuration. A scan of the top gate voltage generates a resistance peak in ambiploar response. The ambipolar peak is shifted by the bottom gate voltage, where the shift rate depends on the graphite thickness. The thickness-dependent peak shift was clarified in terms of the inter-layer screening length to the electric field in the double-gated graphite film. The screening length of 1.2 nm was experimentally obtained.