Materials often exhibit new properties when their crystal lattice is deformed. Applying uniaxial strain to a vdW heterostructure breaks its rotational symmetry and modifies its electronic band structure. Many of the exotic states in these materials, including superconductivity, emerge from a set of closely competing ground states, so even small strains can shift the balance between them and reveal the symmetry of the underlying order.

At very high pressures, the individual crystal layers of a vdW heterostructure are compressed towards one another. This can significantly enhance the electronic coupling between layers, driving potential reconstructions of the atomic lattice and emergent electronic states. For example, applying pressure to twisted bilayer graphene can dynamically tune the existence and strength of superconductivity and other correlated states.

We are developing new experimental techniques for applying high pressure to vdW heterostructures and for continuously tuning their uniaxial strain at millikelvin temperatures, and using them to control and characterize the exotic electronic states which emerge.