Quantum limits to chiroptical molecular discrimination

Mikael P. Backlund

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arXiv · 2607.19136

Quantum limits to chiroptical molecular discrimination

Mikael P. Backlund

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Abstract

Discriminating enantiomer pairs is of central importance in the molecular sciences. The preferential interaction between chiral light and matter is commonly employed in this discrimination, despite fundamental challenges. Here we present quantitative error bounds for classifying the handedness of a chiral, randomly oriented, quantum optical emitter from the perspective of classical and quantum hypothesis testing. Most interestingly, we find that a collective measurement on $N$ photons can provide an orders-of-magnitude improvement in error rate relative to a corresponding separable measurement.

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Mikael P. Backlund. 2026-07-21. Quantum limits to chiroptical molecular discrimination. https://arxiv.org/abs/2607.19136

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