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Biexcitons in monolayer transition metal dichalcogenides tuned by magnetic fields.

ABSTRACT: We present time-integrated four-wave mixing measurements on monolayer MoSe₂ in magnetic fields up to 25 T. The experimental data together with time-dependent density function theory calculations provide interesting insights into the biexciton formation and dynamics. In the presence of magnetic fields the coherence at negative and positive time delays is dominated by intervalley biexcitons. We demonstrate that magnetic fields can serve as a control to enhance the biexciton formation and help search for more exotic states of matter, including the creation of multiple exciton complexes and excitonic condensates.

SUBMITTER: Stevens CE

PROVIDER: S-EPMC6137096 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Biexcitons in monolayer transition metal dichalcogenides tuned by magnetic fields.

Stevens Christopher E CE Paul Jagannath J Cox Timothy T Sahoo Prasana K PK Gutiérrez Humberto R HR Turkowski Volodymyr V Semenov Dimitry D McGill Steven A SA Kapetanakis Myron D MD Perakis Ilias E IE Hilton David J DJ Karaiskaj Denis D

Nature communications 20180913 1

We present time-integrated four-wave mixing measurements on monolayer MoSe<sub>2</sub> in magnetic fields up to 25 T. The experimental data together with time-dependent density function theory calculations provide interesting insights into the biexciton formation and dynamics. In the presence of magnetic fields the coherence at negative and positive time delays is dominated by intervalley biexcitons. We demonstrate that magnetic fields can serve as a control to enhance the biexciton formation an ...[more]

PMID: 30213976

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