Recently achieved two-component dipolar Bose-Einstein condensates open exciting possibilities for the study of mixtures of ultradilute quantum liquids. While nondipolar self-bound (without external confinement) mixtures are necessarily miscible with an approximately fixed ratio between the two densities, the density ratio for the dipolar case is free. Therefore, self-bound dipolar mixtures present qualitatively novel and much richer physics, characterized by three possible ground-state phases: miscible, symmetric immiscible, and asymmetric immiscible, which may in principle occur at any population imbalance. Self-bound immiscible droplets are possible due to mutual nonlocal intercomponent attraction, which results in the formation of a droplet molecule. Moreover, our analysis of the impurity regime shows that quantum fluctuations in the majority component crucially modify the miscibility of impurities. Our work opens intriguing perspectives for the exploration of spinor physics in ultradilute liquids, which should resemble to some extent that of ${}^4\mathrm{He}–{}^3\mathrm{He}$ droplets and impurity-doped helium droplets.

中文翻译：

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偶极混合物的量子滴

最近获得的两组分偶极玻色-爱因斯坦凝聚体为研究超稀量子液体的混合物提供了令人兴奋的可能性。尽管非偶极自结合（无外部约束）混合物必须以两种密度之间的近似固定比率互溶，但偶极情况下的密度比是自由的。因此，自结合的偶极混合物在质量上呈现出新颖且丰富得多的物理学，其特征在于三种可能的基态相：可混溶，对称不混溶和非对称不混溶，原则上在任何人口失衡下都可能发生。由于相互之间的局部非局部相互吸引，自结合的不混溶液滴是可能的，这导致液滴分子的形成。此外，我们对杂质状态的分析表明，主要成分中的量子涨落至关重要地改变了杂质的混溶性。我们的工作为探索超稀液体中的旋子物理学开辟了有趣的视角，在某种程度上应类似于${}^4他–{}^3他$ 滴和杂质掺杂的氦滴。