Field-effect chirality devices with Dirac semimetal

TL;DR

This paper demonstrates field-effect devices using Dirac semimetal PtSe2 that can control chiral anomaly currents with high ON/OFF ratios, enabling logic functions with low dissipation.

Contribution

It introduces a novel field-effect device based on Dirac semimetal PtSe2 that can electrically modulate chiral anomaly currents, a significant step forward in low-dissipation electronics.

Findings

Chiral anomaly current can be modulated by electrostatic gating.

Nonlocal valley transport with micrometer diffusion length is demonstrated.

Devices achieve ON/OFF ratios exceeding 10^3 and perform basic logic functions.

Abstract

Charge-based field-effect transistors (FETs) greatly suffer from unavoidable carrier scattering and heat dissipation. In analogy to valley degree of freedom in semiconductors, chiral anomaly current in Weyl/Dirac semimetals is theoretically predicted to be nearly non-dissipative over long distances, but still lacks experimental ways to efficiently control its transport. Here we demonstrate field-effect chirality devices with Dirac semimetal PtSe2, in which its Fermi level is close to the Dirac point in conduction band owing to intrinsic defects. The chiral anomaly is further corroborated with nonlocal valley transport measurement, which can also be effectively modulated by external fields, showing robust nonlocal valley transport with micrometer diffusion length. Similar to charge-based FETs, the chiral conductivity in PtSe2 devices can be modulated by electrostatic gating with an ON/OFF ratio more than 103. We also demonstrate basic logic functions in the devices with electric and magnetic fields as input signals.