Washington: Researchers have invented a tiny laser -- a thousand times thinner than a single human hair -- that is capable of functioning inside living tissues without harming them, an advance that could improve diagnosis and treatment for neurological disorders like epilepsy. The laser, developed by researchers at Northwestern and Columbia Universities in the US, is just 50 to 150 nanometres thick.
The study, published in the journal Nature Materials, noted that the laser can fit and function inside living tissues, and could be used to sense disease characteristics in tissues, or in treating deep-brain neurological disorders like epilepsy.
The nanolaser, according to the researchers, is specifically promising for imaging living tissues. The laser is made mostly of glass, which the researchers said made it biocompatible. Traditionally, according to the researchers, nanolasers were much less efficient than macroscopic ones, and used shorter wavelengths, such as ultraviolet (UV) light.
"This is bad because the unconventional environments in which people want to use small lasers are highly susceptible to damage from UV light, and the excess heat generated by inefficient operation," said P. James Schuck, co-author from Columbia University's School of Engineering. But the new laser, they said, can be excited with longer wavelengths of light and emit at shorter wavelengths.
"Longer wavelengths of light are needed for bioimaging because they can penetrate farther into tissues than visible wavelength photons," said Teri Odom, who co-led the research from Northwestern University in the US. Odom added that shorter wavelengths of light are often desirable at those same deep areas.