Interfacial Ferroelectric Moments Probed by Hysteretic Transport in Graphene/hBN/α−RuCl3 Heterostructures

Understanding and engineering interface states are essential for the development of novel nano-electronic devices. An interfacial electric polarization can emerge across material heterojunctions and lead to a nontrivial response to external fields. Here we identify a tunable interfacial polarization in graphene/hBN/α−RuCl3 field effect devices through hysteretic transport measurements. The interfacial polarization originates from quantum mechanical exchange interactions, and do not involve any charge transfer across the interface. It can be manipulated by externally applied electric fields and behaves like a switchable ferroelectric moment. Our work unveils a novel route towards engineering ferroelectric like behavior in non-ferroelectric materials.