Laser from carrots: IIT-M research open up new possibility in optical spectroscopy, sensing

Exploiting a process first discovered by Nobel laureate C V Raman, researchers at IIT-Madras Monday claimed to have generated laser from carrots, promising key advancements in research in optical spectroscopy and sensing.

A team comprising Professor C Vijayan and Assistant Professor Sivarama Krishnan from the Physics Department and a Ph.D. scholar used a process first discovered by Nobel Laureate C V Raman in this research, the Indian Institute of Technology, Madras said in a release.

IIT-M "researchers have demonstrated the possibility of generating bio-compatible lasers from carrots, exploiting a process first discovered by C V Raman," it said.

"This finding by the IIT Madras team, a first of its kind development even globally, promises significant advancements in scientific and industrial research on optical spectroscopy and sensing," it said.

Apart from being bio-friendly, the system they envisage was robust and reliable, with good and linear response to temperature, it said.

According to the release, lasers were 'ubiquitous' sources of light with extraordinary properties such as a high degree of directionality and sharpness.

They were indispensable in a range of products and technologies, including communication, lithography, medicine, military operations, scientific research, engineering, displays, and data storage, it said.

"In this case, a particular class of lasers called random lasers have been demonstrated in carrots where a Raman process plays a central role along with the cellulose network," it added.

Krishnan said organic bio-pigments like carotenoids found in carrots and porphyrins found in chlorophyll were interesting optically active media because of their visible light absorption properties.

"Although the fluorescence quantum yield of carotenoids is much less compared to standard organic laser dyes, the vibrational spectra can be obtained even with extremely low concentrations of carotenoids.

"The research team naturally chose carotenoid, as a possible lasing source," he said.

In addition to having carotenoids, carrots also have cellulose fibres that contribute to multiple scattering of photons and resultant optical amplification, the release said.