Exciton density waves in Coulomb-coupled dual moiré lattices
Exciton density waves in Coulomb-coupled dual moiré lattices
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DOI：
10.1038/s41563-022-01454-4
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发表时间：
2022-05
期刊：
影响因子：
41.2
通讯作者：
Y. Zeng;Zhengchao Xia;Roei Dery;Kenji Watanabe;T. Taniguchi;J. Shan;K. Mak
中科院分区：
文献类型：
--
作者：
Y. Zeng;Zhengchao Xia;Roei Dery;Kenji Watanabe;T. Taniguchi;J. Shan;K. Mak
晶格中的强关联玻色子是实现物质丰富玻色态和量子相变的平台。虽然已经在冷原子实验中研究了晶格中的强关联玻色子，但它们在固态系统中的实现仍然具有挑战性。在这里，我们将层间激子--由束缚电子-空穴对组成的玻色子--捕获在角向排列的WS2/双层WSe2/WS2多层膜提供的晶格中。这种异质结构支持顶部和底部界面具有几乎相同周期的库仑耦合三角莫尔晶格。当具有任意分割的两个晶格的电子填充因子之和为AND时，我们观察到关联绝缘态。这些态可以解释为激子和空穴的玻色-费米混合物中的激子密度波。由于组分之间强烈的排斥相互作用，空穴形成了健壮的广义维格纳晶体，-，它将激子流体限制在自发破坏晶格平移对称性的通道中。我们的结果表明，库仑耦合的莫尔晶格是相关多玻色子现象的沃土。
Strongly correlated bosons in a lattice are a platform that can realize rich bosonic states of matter and quantum phase transitions. While strongly correlated bosons in a lattice have been studied in cold-atom experiments, –, their realization in a solid-state system has remained challenging. Here we trap interlayer excitons–bosons composed of bound electron–hole pairs, in a lattice provided by an angle-aligned WS2/bilayer WSe2/WS2multilayer. The heterostructure supports Coulomb-coupled triangular moiré lattices of nearly identical period at the top and bottom interfaces. We observe correlated insulating states when the combined electron filling factor of the two lattices, with arbitrary partitions, equalsand. These states can be interpreted as exciton density waves in a Bose–Fermi mixture of excitons and holes,. Because of the strong repulsive interactions between the constituents, the holes form robust generalized Wigner crystals, , –, which restrict the exciton fluid to channels that spontaneously break the translational symmetry of the lattice. Our results demonstrate that Coulomb-coupled moiré lattices are fertile ground for correlated many-boson phenomena,.