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Pseudo-heterostructure and condensation of 1D moire excitons in twisted phosphorene bilayers.

ABSTRACT: Heterostructures are not expected to form in a single homogeneous material. Here, we show that planar pseudo-heterostructures could emerge in a twisted bilayer of phosphorene (tbP), driving in-plane energy and charge transfer. The formation of moiré superlattices combined with electronic anisotropy in tbPs yields one-dimensional (1D) moiré excitons with long radiative and nonradiative lifetimes, large binding energies, and deep moiré potentials. Low-frequency moiré phonons and dynamic moiré potentials are revealed to be responsible for the in-plane energy/charge transfer and exciton dynamics. The 1D moiré excitons are predicted to exhibit Bose-Einstein condensation at high temperatures and may lead to exotic Tonks-Girardeau Bose gases.

SUBMITTER: Guo H

PROVIDER: S-EPMC10361592 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

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Pseudo-heterostructure and condensation of 1D moiré excitons in twisted phosphorene bilayers.

Guo Hongli H Zhang Xu X Lu Gang G

Science advances 20230721 29

Heterostructures are not expected to form in a single homogeneous material. Here, we show that planar pseudo-heterostructures could emerge in a twisted bilayer of phosphorene (tbP), driving in-plane energy and charge transfer. The formation of moiré superlattices combined with electronic anisotropy in tbPs yields one-dimensional (1D) moiré excitons with long radiative and nonradiative lifetimes, large binding energies, and deep moiré potentials. Low-frequency moiré phonons and dynamic moiré pote ...[more]

PMID: 37478184

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