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Bottom-up Analysis of Rovibrational Helical Dichroism
Mateja Hrast1, Georgios M Koutentakis1, Mikhail Maslov1
1Institute of Science and Technology Austria (ISTA), Am Campus 1, 3400 Klosterneuburg, Austria.
Physical Review Letters
|February 22, 2026
Summary
We developed a theory linking chiral resolution and orbital angular momentum (OAM) exchange. Helical dichroism (HD) arises from light
Area of Science:
- * Physics
- * Physical Chemistry
- * Optics
Background:
- * Chirality is a fundamental property in chemistry and physics.
- * Helical dichroism (HD) is an optical phenomenon sensitive to molecular chirality.
- * Understanding the fundamental mechanisms of HD is crucial for advanced applications.
Purpose of the Study:
- * To present a general theoretical framework for helical dichroism (HD).
- * To establish a link between chiral resolution and orbital angular momentum (OAM) exchange.
- * To refine the conditions for observing HD and guide future chiral sensing designs.
Main Methods:
- * Development of a theoretical framework for light-matter interaction.
- * Microscopic analysis of orbital angular momentum (OAM) transfer.
- * Derivation of rotational selection rules.
Main Results:
- * An explicit link between chiral resolution and OAM exchange was established.
- * Helical dichroism (HD) was shown to emerge from the spin-orbit coupling of light.
- * Rotational selection rules governing HD were derived, even for beams without far-field OAM.
Conclusions:
- * HD is fundamentally linked to the spin-orbit coupling of light.
- * The theoretical framework refines conditions for observing HD.
- * Findings guide future chiral sensing technologies using structured light.
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