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arXiv · 2101.00953

Exciton radiative lifetime in a monoatomic carbon chain

Stella Kutrovskaya·Sevak Demirchyan·Anton Osipov·Stepan Baryshev·Anton Zasedatelev·Pavlos Lagoudakis·Alexey Kavokin
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Abstract

Linear carbon-based materials such as polyyne and cumulene oligomers provide a versatile platform for nano-physics and engineering. Direct gap quasi-1D polyyne structures are promising for the observation of strong and unusual excitonic eects arising due to the two-dimensional quantum connement. Recently, we reported on the observation of sharp exciton peaks in low temperature photoluminescence spectra of polyyne chains. Here, we analyse the time-resolved optical response of this system. We extend the non-local dielectric response theory to predict the exciton radiative lifetime dependence on the band-gap value and on the length of the chain. A good agreement between the experiment and the theory is achieved.

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Stella Kutrovskaya, Sevak Demirchyan, Anton Osipov, Stepan Baryshev, Anton Zasedatelev, Pavlos Lagoudakis, Alexey Kavokin. 2020-12-26. Exciton radiative lifetime in a monoatomic carbon chain. https://arxiv.org/abs/2101.00953

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