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arXiv · 2307.13688

Correlated insulator in two Coulomb-coupled quantum wires

Yang-Zhi Chou·Sankar Das Sarma
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Abstract

Motivated by the recently discovered incompressible insulating phase in the bilayer graphene exciton experiment [arXiv:2306.16995], we study using bosonization two Coulomb-coupled spinless quantum wires and examine the possibility of realizing the similar phenomenology in one dimension. We explore the possible phases as functions of $k_{F}$'s and interactions. We show that an incompressible insulating phase can arise for two lightly doped electron-hole quantum wires (i.e., $k_{F1}=-k_{F2}$ and small $|k_{F1}|$) due to strong interwire interactions. Such an insulating phase forms a parity-even wire-antisymmetric charge density wave without interwire phase coherence, which melts to a phase allowing for a perfect negative drag upon heating. The finite-temperature response is qualitatively consistent with the ``exciton solid'' phenomenology in the bilayer graphene exciton experiment.

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Yang-Zhi Chou, Sankar Das Sarma. 2023-07-25. Correlated insulator in two Coulomb-coupled quantum wires. https://doi.org/10.1103/physrevb.108.235135

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