Light travels through opaque objects in random paths that are difficult to control but, thanks to new research by a team of physicists, light energy can be concentrated at a certain depth. This means that physicists could potentially target specific neurons or even early tumors inside tissue, which is known to usually strongly scatter light.
Dr. Alexey Yamilov, professor of physics at Missouri University of Science and Technology, along with a team of researchers led by Yale University, recently published an article in the journal Nature Physics titled “Depth-targeted energy delivery deep inside scattering media.” In it, they describe a process to have optical energy enhanced at specific locations inside light-guiding structures called waveguides and predict the limit for such enhancements.
The researchers’ new approach could lead to advances in light-based medical technology. By observing undisturbed paths of light while it travels through scattering materials the researchers demonstrate that it is possible to enhance and suppress energy density at specific locations inside a scattering sample.
The work was accomplished by observing how light travels through a medium. To do this, the researchers devised a simulated tissue in a two-dimensional sample and developed a model and computer simulations to make predictions for 3D applications.
“For decades, scientists have been improving ways and methods to concentrate light in specific areas of tissue,” says Yamilov. “This new study sets the fundamental limit for deep-tissue imaging, optogenetics, photothermal therapy and other applications.”
The work builds on previous research that Yamilov and the team have conducted. Throughout a 10-year-old collaboration to investigate the interplay between lightwave scattering and interference, the researchers were led to the breakthrough while studying of transmission eigenchannels, which are wave patterns specific to a particular sample.
“This research not only has applications in the field of optics, but also profound implications in condensed matter physics, acoustics, and other fields involving wave propagation and scattering,” says Yamilov. “It offers a glimpse of undiscovered physics and I hope it spurs on more interest from biologists and engineers to further improve their techniques on the way of approaching the physical limit found in this work.”
About Missouri University of Science and Technology
Missouri University of Science and Technology (Missouri S&T) is a STEM-focused research university of over 7,200 students. Part of the four-campus University of Missouri System and located in Rolla, Missouri, Missouri S&T offers 101 degrees in 40 areas of study and is among the nation’s top 10 universities for return on investment, according to Business Insider. S&T also is home to the Kummer Institute, made possible by a $300 million gift from Fred and June Kummer. For more information about Missouri S&T, visit www.mst.edu.