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DOE OSTI · 1388202

Interlayer excitons with tunable dispersion relation

Skinner, Brian
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Abstract

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. Finally, this diversity suggests a platform for continuously tuning between different quantum phases using an external field.

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BibTeXRIS

Skinner, Brian. 2016-06-07. Interlayer excitons with tunable dispersion relation. https://doi.org/10.1103/physrevb.93.235110

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