Orbital XY models in moiré superlattices  

作　　者：Yanqi Li Yi-Jie Wang Zhi-Da Song 李彦琪;王一杰;宋志达

机构地区：[1]International Center for Quantum Materials,School of Physics,Peking University,Beijing 100871,China [2]Hefei National Laboratory,Hefei 230088,China [3]Collaborative Innovation Center of Quantum Matter,Beijing 100871,China

出　　处：《Chinese Physics B》2025年第2期19-29,共11页中国物理B(英文版)

基　　金：Project supported by the National Natural Science Foundation of China (Grant No. 12274005);the National Key Research and Development Program of China (Grant No. 2021YFA1401903);Innovation Program for Quantum Science and Technology (Grant No. 2021ZD0302403)。

摘　　要：Moiré superlattices provide a new platform to engineer various many-body problems. In this work, we consider arrays of quantum dots(QD) realized on semiconductor moiré superlattices with a deep moiré potential. We diagonalize single QD with multiple electrons, and find degenerate ground states serving as local degrees of freedom(qudits) in the superlattice. With a deep moiré potential, the hopping and exchange interaction between nearby QDs become irrelevant,and the direct Coulomb interaction of the density–density type dominates. Therefore, nearby QDs must arrange the spatial densities to optimize the Coulomb energy. When the local Hilbert space has a two-fold orbital degeneracy, we find that a square superlattice realizes an anisotropic XY model, while a triangular superlattice realizes a generalized XY model with geometric frustration.

关 键 词：moirésuperlattices quantum dots XY model 

分 类 号：O17[理学—数学]