Recognizing molecular chirality via twisted 2D materials

Lorenzo Cavicchi; Mayra Peralta; Álvaro Moreno; Maia Vergniory; Pablo Jarillo-Herrero; Claudia Felser; Giuseppe C. La Rocca; Frank H. L. Koppens; Marco Polini

arXiv · 2409.05839

Recognizing molecular chirality via twisted 2D materials

Lorenzo Cavicchi·Mayra Peralta·Álvaro Moreno·Maia Vergniory·Pablo Jarillo-Herrero·Claudia Felser·Giuseppe C. La Rocca·Frank H. L. Koppens·Marco Polini

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Abstract

Chirality pervades natural processes from the atomic to the cosmic scales, crucially impacting molecular chemistry and pharmaceutics. Traditional chirality sensing methods face challenges in sensitivity and efficiency, prompting the quest of novel chiral recognition solutions based on nanophotonics. In this work we theoretically investigate the possibility to carry out enantiomeric discrimination by measuring the spontaneous emission rate of chiral molecules on twisted two-dimensional materials. We first present a general theoretical framework based on dyadic Green's functions to calculate the chiral contribution to the decay rate in the presence of a generic chiral bilayer interface. We then combine this theory with density functional theory to obtain numerical estimates of the decay rate of helical bilayer nanographene molecules placed on top of twisted bilayer graphene.

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Lorenzo Cavicchi, Mayra Peralta, Álvaro Moreno, Maia Vergniory, Pablo Jarillo-Herrero, Claudia Felser, Giuseppe C. La Rocca, Frank H. L. Koppens, Marco Polini. 2024-09-09. Recognizing molecular chirality via twisted 2D materials. https://arxiv.org/abs/2409.05839

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