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Destructive Photon Echo Formation in Six-Wave Mixing Signals of a MoSe₂ Monolayer.

ABSTRACT: Monolayers of transition metal dichalcogenides display a strong excitonic optical response. Additionally encapsulating the monolayer with hexagonal boron nitride allows to reach the limit of a purely homogeneously broadened exciton system. On such a MoSe₂ -based system, ultrafast six-wave mixing spectroscopy is performed and a novel destructive photon echo effect is found. This process manifests as a characteristic depression of the nonlinear signal dynamics when scanning the delay between the applied laser pulses. By theoretically describing the process within a local field model, an excellent agreement with the experiment is reached. An effective Bloch vector representation is developed and thereby it is demonstrated that the destructive photon echo stems from a destructive interference of successive repetitions of the heterodyning experiment.

SUBMITTER: Hahn T

PROVIDER: S-EPMC8728888 | biostudies-literature |

REPOSITORIES: biostudies-literature

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