Interface engineering of van der Waals heterostructures towards energy-efficient quantum devices operating at high temperatures

TL;DR

This review discusses recent advances in van der Waals heterostructures, focusing on interface engineering to enable high-temperature quantum devices with emergent quantum phenomena like exciton condensation and topological superconductivity.

Contribution

It summarizes recent research on quantum phenomena in vdW heterostructures and proposes structures for high-temperature quantum devices, advancing practical quantum technology.

Findings

Emergent quantum phenomena observed in vdW heterostructures.

Potential for high-temperature quantum devices using interface engineering.

Proposals for structures supporting Majorana zero modes at elevated temperatures.

Abstract

Quantum devices, which rely on quantum mechanical effects for their operation, may offer advantages, such as reduced dimensions, increased speed, and energy efficiency, compared to conventional devices. However, quantum phenomena are typically observed only at cryogenic temperatures, which limits their practical applications. Two-dimensional materials and their van der Waals (vdW) heterostructures provide a promising platform for high-temperature quantum devices owing to their strong Coulomb interactions and/or spin-orbit coupling. In this review, we summarise recent research on emergent quantum phenomena in vdW heterostructures based on interlayer tunnelling and the coupling of charged particles and spins, including negative differential resistance, Josephson tunnelling, exciton condensation, and topological superconductivity. These are the underlying mechanisms of energy-efficient devices, including tunnel field-effect transistors, topological/superconducting transistors, and quantum computers. The natural homojunction within vdW layered materials offers clean interfaces and perfectly aligned structures for enhanced interlayer coupling. Twisted bilayers with small angles may also give rise to novel quantum effects. In addition, we highlight several proposed structures for achieving high-temperature Majorana zero modes, which are critical elements of topological quantum computing. This review is helpful for researchers working on interface engineering of vdW heterostructures towards energy-efficient quantum devices operating above the liquid nitrogen temperature.