论文标题
一对2D量子液体：研究间接激子的相位行为
A Pair of 2D Quantum Liquids: Investigating the Phase Behavior of Indirect Excitons
论文作者
论文摘要
长期寿命的间接激子（IXS）显示了丰富的相图，包括玻色子凝结物（BEC），Wigner晶体和其他外来相位。最近的实验暗示了在BEC过渡上方的IXS的一种新的“经典”液体。为了揭示此阶段的性质，我们使用了广泛的理论工具，也没有找到朝着古典凝结驱动力的证据。取而代之的是，我们将凝结相归因于量子电子孔液体（EHL），这是Keldysh首次提出的直接激子。考虑到自由载流子与绑定激子的关联，我们研究了激气子的气体，自由载体的气体和EHL之间的相平衡，用于广泛的电子孔分离，温度，密度和质量比。我们的结果与最近对GAAS/藻类耦合量子井的测量非常吻合。
Long-lived indirect excitons (IXs) exhibit a rich phase diagram, including a Bose-Einstein condensate (BEC), a Wigner crystal, and other exotic phases. Recent experiments have hinted at a new, "classical" liquid of IXs above the BEC transition. To uncover the nature of this phase, we use a broad range of theoretical tools and find no evidence of a driving force towards classical condensation. Instead, we attribute the condensed phase to a quantum electron-hole liquid (EHL), first proposed by Keldysh for direct excitons. Taking into account the association of free carriers into bound excitons, we study the phase equilibrium between a gas of excitons, a gas of free carriers, and an EHL for a wide range of electron-hole separations, temperatures, densities, and mass ratios. Our results agree reasonably well with recent measurements of GaAs/AlGaAs coupled quantum wells.
