Researchers from IIT Bombay led by Prof. Gopal Dixit, Department of Physics; Tata Institute of Fundamental Research (TIFR) and IIT Hyderabad have developed a novel optical technique to distinguish between mirror-image molecules, known as enantiomers, using specially structured “twisted” laser light. Published in Science Advances, the study demonstrates that laser beams carrying orbital angular momentum interact differently with chiral molecules depending on their handedness.

The researchers directed ultrashort twisted laser pulses onto gaseous samples of R- and S-camphor. The interaction ionized the molecules, causing them to fragment into charged particles that were analyzed using a time-of-flight mass spectrometer. They observed that the number of fragments produced varied according to the combination of the molecule’s handedness and the light’s twist, enabling direct discrimination between enantiomers.

Unlike conventional chirality-detection methods that require complex measurements, this approach relies on simple ion-counting signals, offering enhanced sensitivity and experimental simplicity. The technique could provide a powerful new tool for chemical, biological, and pharmaceutical analysis.