We explore quantum materials — using hierarchical first-principles quantum theories and model Hamiltonians.
We have been deeply interested in 2D magnetism, extensively exploring edge magnetism in graphene and ways to induce long-range ordering in otherwise non-magnetic 2D materials. Following the 2017 discovery of monolayer CrI3—which seemingly defied the Hohenberg–Mermin–Wagner theorem—our research shifted toward intrinsically magnetic 2D materials. Our current efforts focus on designing high-temperature 2D magnets by manipulating intrinsic exchange interactions through external perturbations, such as electrostatic gating. More recently, we have expanded our scope to non-van der Waals ultrathin correlated oxides as novel 2D platforms.
Topology has revolutionized modern condensed matter physics by giving rise to symmetry-protected quantum states. Here, we explore how the geometric properties of quantum wavefunctions govern novel phenomena, investigating effects driven by both the real part (quantum metric) and the imaginary part (Berry curvature) of the quantum geometric tensor. We place special emphasis on materials where the interplay of magnetism and topology gives rise to exotic electronic and transport properties.
Perovskite oxides serve as a rich playground for investigating the complex interplay among electron correlations, spin-orbit coupling, and lattice distortions. By exploring their vast chemical space, we aim to uncover and design their functional properties.
Kagome materials have coexisting Dirac crossings, flat bands, and van Hove singularities, which drive unconventional superconductivity, charge density waves, and complex magnetism. We explore their highly tunable electronic structures to engineer and understand diverse correlated and topological states of matter.
We explore heterostructures combining materials with distinct quantum states,often hosting exotic emergent physics. Specifically, we investigate 2D electron gases at oxide interfaces as well as all-2D vdW heterostructures combining a ferromagnet with a metal, semiconductor, superconductor, or topological insulator. These systems provide a versatile platform to manipulate valley physics, control topological quantum states, and engineer exotic quasiparticles such as Majorana fermions.
The interaction of electrons with underlying lattice vibrations provides a window into dissipationless electrical transport, while phonon–phonon interactions govern lattice thermal conductivity. Furthermore, light–matter interactions allow us to probe exciton physics and optical responses, such as Raman scattering. We explore these complex interactions in a diverse range of materials.
