Quantum computation with graphene nanoribbon

TL;DR

This paper proposes a scalable quantum computing scheme using graphene nanoribbons, where localized electron spins in quantum dots serve as qubits, enabling universal quantum computation with current techniques.

Contribution

It introduces a novel method to implement quantum computation in graphene nanoribbons without confinement gates, utilizing natural localization and control strategies.

Findings

Electron or hole localization in zigzag regions of graphene nanoribbons

Formation of a one-dimensional chain of graphene quantum dots

Universal quantum computation achievable with bang-bang control and decoherence-free subspaces

Abstract

We propose a scalable scheme to implement quantum computation in graphene nanoribbon. It is shown that electron or hole can be naturally localized in each zigzag region for a graphene nanoribbon with a sequence of Z-shaped structure without exploiting any confined gate. An one-dimensional graphene quantum dots chain is formed in such graphene nanoribbon, where electron or hole spin can be encoded as qubits. The coupling interaction between neighboring graphene quantum dots is found to be always-on Heisenberg type. Applying the bang-bang control strategy and decoherence free subspaces encoding method, universal quantum computation is argued to be realizable with the present techniques.