Dynamic Interfacial Quantum Dipoles in Charge Transfer Heterostructures

TL;DR

This paper uncovers a new hysteresis mechanism in graphene/hBN/RuCl3 heterostructures driven by dynamic interfacial quantum dipoles, enabling tunable nanoelectronic device functionalities.

Contribution

It introduces a novel hysteresis mechanism based on quantum exchange interactions at interfaces, distinct from traditional memory devices.

Findings

Hysteresis appears sharply at low temperatures.

Hysteresis can be tuned by external electrical bias.

Interfacial quantum dipoles induce the hysteretic behavior.

Abstract

Hysteretic gate responses of two-dimensional material heterostructures serve as sensitive probes of the underlying electronic states and hold significant promise for the development of novel nanoelectronic devices. Here we identify a new mechanism of hysteretic behavior in graphene/$h$BN/$\alpha$-$\mathrm{RuCl_3}$ charge transfer field effect devices. The hysteresis loop exhibits a sharp onset under low temperatures and evolves symmetrically relative to the charge transfer equilibrium. Unlike conventional flash memory devices, the charge transfer heterostructure features a transparent tunneling barrier and its hysteretic gate response is induced by the dynamic tuning of interfacial dipoles originating from quantum exchange interactions. The system acts effectively as a ferroelectric and gives rise to remarkable tunability of the hysteretic gate response under external electrical bias. Our work unveils a novel mechanism for engineering hysteretic behaviors via dynamic interfacial quantum dipoles.