Zhang Naiyuan J, Nguyen Ron Q, Batra Navketan, Liu Xiaoxue, Watanabe Kenji, Taniguchi Takashi, Feldman D E, Li J I A
Department of Physics, Brown University, Providence, RI, USA.
Brown Theoretical Physics Center, Brown University, Providence, RI, USA.
Nature. 2025 Jan;637(8045):327-332. doi: 10.1038/s41586-024-08274-3. Epub 2025 Jan 8.
Excitons, Coulomb-driven bound states of electrons and holes, are typically composed of integer charges. However, in bilayer systems influenced by charge fractionalization, a more interesting form of interlayer exciton can emerge, in which pairing occurs between constituents that carry fractional charges. Despite numerous theoretical predictions for these fractional excitons, their experimental observation has remained unexplored. Here we report transport signatures of excitonic pairing in fractional quantum Hall effect states. By probing the composition of these excitons and their impact on the underlying wavefunction, we discover two new types of quantum phases of matter. One of these can be viewed as the fractional counterpart of the exciton condensate at a total filling of 1, whereas the other involves a more unusual type of exciton that obeys non-bosonic quantum statistics, challenging the standard model of bosonic excitons.
激子是由库仑力驱动的电子和空穴的束缚态，通常由整数电荷组成。然而，在受电荷分数化影响的双层系统中，可能会出现一种更有趣的层间激子形式，其中携带分数电荷的组分之间会发生配对。尽管对这些分数激子有众多理论预测，但它们的实验观测仍未得到探索。在此，我们报告分数量子霍尔效应态中激子配对的输运特征。通过探测这些激子的组成及其对底层波函数的影响，我们发现了两种新的物质量子相。其中一种可被视为总填充数为1时激子凝聚体的分数对应物，而另一种涉及一种更不寻常的激子，它服从非玻色子量子统计，这对玻色子激子的标准模型提出了挑战。
