Strong interactions and isospin symmetry breaking in a supermoiré lattice
Yonglong Xie, Andrew Pierce, Jeong Min Park, Daniel E. Parker, Jie Wang, Patrick J. Ledwith, Zhuozhen Cai, Kenji Watanabe, Takashi Taniguchi, Eslam Khalaf, Ashvin Vishwanath, Pablo Jarillo‐Herrero, Amir Yacoby
Abstract
In multilayer moiré heterostructures, the interference of multiple twist angles ubiquitously leads to tunable ultralong-wavelength patterns known as supermoiré lattices. However, their impact on the system's many-body electronic phase diagram remains largely unexplored. We present local compressibility measurements revealing numerous incompressible states resulting from supermoiré lattice-scale isospin symmetry breaking driven by strong interactions. By using the supermoiré lattice occupancy as a probe of isospin symmetry, we observed an unexpected doubling of the miniband filling near [Formula: see text], possibly indicating a hidden phase transition or normal-state pairing proximal to the superconducting phase. Our work establishes supermoiré lattices as a tunable parameter for designing quantum phases and as an effective tool for unraveling correlated phenomena in moiré materials.