Interlayer excitons with tunable dispersion relation
Interlayer excitons with tunable dispersion relation
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DOI：
10.1103/physrevb.93.235110
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发表时间：
2016-01
影响因子：
3.7
通讯作者：
B. Skinner
中科院分区：
文献类型：
--
作者：
B. Skinner
层间激子是一种复合玻色子，它由一种材料中的一个电子被库仑吸引到邻近材料中的一个空穴所束缚，可以采用各种多体相。玻色子系统的相图在很大程度上由玻色子的色散关系决定，而玻色子的色散关系本身是电子和空穴的色散关系的组合。在这里，我指出，在电子或空穴具有非单调的‘墨西哥帽状’色散关系的情况下，激子色散关系可以具有一系列定性不同的形式，每一种形式对应于低温下的不同多体相。这种多样性提供了一个利用外场在不同量子相之间连续调谐的平台。
Interlayer excitons, comprising an electron in one material bound by Coulomb attraction to a hole in an adjacent material, are composite bosons that can assume a variety of many-body phases. The phase diagram of the bosonic system is largely determined by the dispersion relation of the bosons, which itself arises as a combination of the dispersion relations of the electron and hole separately. Here I show that in situations where either the electron or the hole has a nonmonotonic, ``Mexican hat-shaped'' dispersion relation, the exciton dispersion relation can have a range of qualitatively different forms, each corresponding to a different many-body phase at low temperature. This diversity suggests a platform for continuously tuning between different quantum phases using an external field.