Gant South Building

Dr. Jacob Pettine​, MITTuning the properties of quantum materials through nanostructured symmetries Fine-tuning interactions and quantum phenomena in materials has been a longstanding challenge, with recent advances in stacked and twisted van der Waals crystals as well as light-driven transient phases. Yet intrinsic lattice symmetries still fundamentally constrain the phases that can be accessed in these systems. The ability to further design these symmetries therefore represents an exciting frontier for controlling both the static properties and ultrafast responses of quantum materials. Although directly engineering the atomic lattice remains a significant challenge, we can nevertheless nudge the symmetries of a material through high-precision nanostructuring, despite the apparent disparity in spatial scales. In this talk, I will discuss recent progress in this direction, including tuning electronic structure via two-dimensional superlattice strain on ultra-fine lithographic arrays and the direct patterning of thin crystals to induce symmetry-tailored dynamical strain fields through ultrafast nano-acoustic modes. Special attention will be given to the photocurrent responses that emerge in centrosymmetric materials such as graphene when patterned with symmetry-broken metasurfaces. These hybrid systems enable nearly arbitrary control over nanoscale vectorial current and provide a novel local probe of electronic anisotropy. Upon ultrafast excitation, they also act as efficient sources of tunable terahertz vector radiation, simultaneously probing the collective material dynamics.Pettine, J. et al. Light-driven nanoscale vectorial currents. Nature 626, 984 (2024) Pettine, J. et al. Ultrafast terahertz emission from emerging symmetry-broken materials. Light Sci. Appl. 12, 133 (2023)