Quantum systems with engineered Hamiltonians can be used to study many-body physics problems to provide insights beyond the capabilities of classical computers. Semiconductor gate-defined quantum dot arrays have emerged as a versatile platform for realizing generalized Fermi-Hubbard physics, one of the richest playgrounds in condensed matter physics. In this work, we employ a germanium $4\times 2$ quantum dot array and show that the naturally occurring long-range Coulomb interaction can lead to exciton formation and transport. We tune the quantum dot ladder into two capacitively coupled channels and exploit Coulomb drag to probe the binding of electrons and holes. Specifically, we shuttle an electron through one leg of the ladder and observe that a hole is dragged along in the second leg under the right conditions. This corresponds to a transition from single-electron transport in one leg to exciton transport along the ladder. Our work paves the way for the study of excitonic states of matter in quantum dot arrays.

中文翻译：

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锗量子点梯中的激子传输

具有工程哈密顿量的量子系统可用于研究多体物理问题，以提供超出经典计算机能力的见解。半导体门定义的量子点阵列已成为实现广义费米-哈伯德物理的多功能平台，这是凝聚态物理中最丰富的游乐场之一。在这项工作中，我们采用了锗$4\times 2$量子点阵列并表明自然发生的长程库仑相互作用可以导致激子的形成和传输。我们将量子点梯调整为两个电容耦合通道，并利用库仑阻力来探测电子和空穴的结合。具体来说，我们将电子穿过梯子的一条腿，并观察到在适当的条件下，第二条腿中的空穴被拖动。这对应于从单腿中的单电子传输到沿梯子的激子传输的转变。我们的工作为量子点阵列中物质激子态的研究铺平了道路。