Revolutionary Graphene Ribbons: The Future of Quantum Innovation Unveiled

Researchers affiliated with the National University of Singapore (NUS) have recently made a remarkable advancement in developing next-generation carbon-based quantum materials, paving the way for progress in quantum electronics.

The innovation centers around a new type of graphene nanoribbon (GNR), referred to as Janus GNR (JGNR). This material features a distinct zigzag edge, possessing a specialized ferromagnetic edge state on one of its sides. This exclusive design facilitates the creation of a one-dimensional ferromagnetic spin chain, which could play a crucial role in quantum electronics and quantum computing.

The study was led by Associate Professor Lu Jiong and his team from the NUS Department of Chemistry, in partnership with collaborators from around the globe.

Graphene nanoribbons, which are slender strips of nanoscale honeycomb carbon configurations, display extraordinary magnetic characteristics due to the behavior of unpaired electrons in the atoms’ π-orbitals. By precisely engineering their edge structures into a zigzag formation at the atomic level, it is possible to establish a one-dimensional spin-polarised channel. This property holds significant promise for applications in spintronic devices or serving as advanced multi-qubit systems that serve as the fundamental components of quantum computing.

Janus, the ancient Roman deity symbolizing beginnings and endings, is frequently portrayed with two faces gazing in opposing directions, signifying the past and the future. The term “Janus” has been adopted in materials science to refer to substances that exhibit distinct properties on either side. JGNR has an innovative configuration, with only one edge of the ribbon displaying a zigzag shape, making it the world’s first one-dimensional ferromagnetic carbon chain. This configuration is attained by utilizing a Z-shaped precursor structure which introduces a periodic arrangement of hexagonal carbon rings on one of the zigzag edges, disrupting the structural and spin symmetry of the ribbon.

Assoc Prof Lu stated, “Magnetic graphene nanoribbons – narrow strips of graphene formed by fused benzene rings – possess immense potential for quantum technologies due to their extended spin coherence times and the capacity to function at room temperature. Fabricating a one-dimensional single zigzag edge in such systems represents a challenging yet essential step for achieving the bottom-up assembly of multiple spin qubits for quantum technologies.”

This significant accomplishment is the result of close cooperation among synthetic chemists, materials scientists, and theoretical physicists, including Professor Steven G Louie from UC Berkeley in the United States, Professor Hiroshi Sakaguchi from Kyoto University in Japan, along with other contributing authors.

The groundbreaking research was published in the scientific journal Nature on 9 January 2025.