Cutshall Jacob, Mahdikhany Fateme, Roche Anna, Shanks Daniel N, Koehler Michael R, Mandrus David G, Taniguchi Takashi, Watanabe Kenji, Zhu Qizhong, LeRoy Brian J, Schaibley John R
Department of Physics, University of Arizona, Tucson, AZ 85721, USA.
McCormick School of Engineering, Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA.
Sci Adv. 2025 Jan 3;11(1):eadr1772. doi: 10.1126/sciadv.adr1772.
Excitons, which are Coulomb bound electron-hole pairs, are composite bosons and thus at low temperature can form a superfluid state with a single well-defined amplitude and phase. We directly image this macroscopic exciton superfluid state in an hBN-separated MoSe-WSe heterostructure. At high density, we identify quasi-long-range order over the entire active area of our sample, through spatially resolved coherence measurements. By varying the exciton density and sample temperature, we map out the phase diagram of the superfluid. We observe the superfluid phase persisting to a temperature of 15 K, which is in excellent agreement with theoretical predictions. This works paves the way to realizing on chip superfluid structures capable of studying fundamental physical behaviors and quantum devices that use superfluidity.
激子是库仑束缚的电子 - 空穴对，属于复合玻色子，因此在低温下可形成具有单一明确振幅和相位的超流态。我们直接成像了hBN分离的MoSe - WSe异质结构中的这种宏观激子超流态。在高密度下，通过空间分辨相干测量，我们在样品的整个有源区域识别出准长程有序。通过改变激子密度和样品温度，我们绘制出了超流体的相图。我们观察到超流相持续到15 K的温度，这与理论预测非常吻合。这项工作为实现能够研究基本物理行为的芯片上超流体结构以及利用超流性的量子器件铺平了道路。
