We introduce density imbalanced electron-hole bilayers at a commensurate $2:1$ density ratio as a platform for realizing novel phases of electrons, excitons, and trions. Through the independently tunable carrier densities and interlayer spacing, competition between kinetic energy, intralayer repulsion, and interlayer attraction yields a rich phase diagram. By a combination of theoretical analysis and numerical calculation, we find a variety of strong-coupling phases in different parameter regions, including quantum crystals of electrons, excitons, and trions. We also propose an “electron-exciton supersolid” phase that features electron crystallization and exciton superfluidity simultaneously. The material realization and experimental signature of these phases are discussed in the context of semiconductor transition metal dichalcogenide bilayers.

中文翻译：

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电子-空穴双层中相应密度的三重子和激子的强耦合相

我们在相应的密度下引入了密度不平衡的电子空穴双层$2：1$密度比作为实现电子、激子和三重子新相的平台。通过独立可调的载流子密度和层间距，动能、层内斥力和层间吸引力之间的竞争产生丰富的相图。通过理论分析和数值计算相结合，我们发现了不同参数区域的多种强耦合相，包括电子、激子和三重子的量子晶体。我们还提出了一种同时具有电子结晶和激子超流动性的“电子激子超固体”相。这些相的材料实现和实验特征在半导体过渡金属二硫属化物双层的背景下进行了讨论。