Haoxin ZHOU

Owing to the exceptional electrical, mechanical, and chemical properties, graphene has been widely studied since its discovery. A few years ago, the discovery of superconductivity and complex phases in graphene multilayer heterostructures with a small twist angle between each layer placed graphene-based materials into another appealing category. This greatly enlarged its potential of application in next-generated integrated circuits, efficient energy transfer, and quantum computation.

These inspirational observations drove us to ask whether the even simpler graphene-based materials, the graphene without a twist, also host such features. To answer the questions, Haoxin Zhou has been focusing on two specific graphene materials. One of them is two stacked sheets of carbon without a twisted angle, called Bernal bilayer graphene. Another system has three stacked sheets of carbon without a twisted angle, called the rhombohedral trilayer graphene. By applying electric and magnetic field, both systems can be induced into various correlated phases. Within the complex phase diagram, the most exotic phase is the spin-polarized superconductor, which is rare in materials. The electric field-controlled switching between magnetic and superconducting states further extends their application in electronics.

Zhou’s work provides a clean and highly tunable platform to study manybody physics. Further investigation on this system may provide guidance on searching or designing new materials with correlated electronic phenomena, including ferromagnetism and superconductivity and push the development of future technologies such as topological quantum computation and efficient energy transportation.