Jian Tang Lab

We explore the frontier where topology intersects with electron correlations in low-dimensional quantum materials and van der Waals heterostructures. By tuning electrostatic gating, layer stacking, twist angle, and proximity to ferromagnets or superconductors, we create and probe new quantum states arising from the interplay of symmetry, topology, electron interactions, and lattice instabilities. Our goal is to uncover novel topological and correlated phases and to advance the understanding and control of emergent phenomena in a series of new quantum materials.

For instance, we recently discovered a dual quantum spin Hall insulator in monolayer TaIrTe₄ (Nature 628, 515, 2024), arising from the interplay of its single-particle topology and density-tuned electron correlations close to low-energy van Hove singularities. The discovery of the dual QSH insulator introduces a new method for creating topological flat minibands through CDW superlattices, which offer a promising platform for exploring time-reversal-symmetric fractional phases. Moreover, we further uncovered the interaction-driven topological phase transition (arXiv:2506.18412) from a quantum spin Hall insulator to a trivial insulator, a higher-order topological insulator, and a metallic phase. More recently, by leveraging second-order nonlinear Hall transport as a probe of quantum geometry, the Berry curvature dipole and quantum metric dipole of these systems have been systematically investigated.