Princeton Engineering

Ekua Bentil hopes to use one of the most cutting-edge lasers in the world to combat a basic, but devastating, problem: illnesses caused by burning firewood indoors.

A graduate student in electrical engineering, Bentil is the recipient of a Technology for Developing Regions fellowship to deploy a gas-sensing system in her native Ghana. Working with researchers at the University of Cape Coast, Bentil will use the system to detect carbon dioxide, ozone and water vapor in the air.

The ultimate goal of the project is to employ the sensor system to detect poisonous gases emitted from burning firewood. In Ghana, fish industry workers often preserve fish by drying it over wood fires in smokehouses, a practice that exposes them to noxious fumes.

“My goal,” Bentil said, “is to find ways, as a scientist and engineer, to make an impact.”

In addition to the Ghana sensor project, Bentil is developing novel techniques to make lasers that emit only one wavelength of light at a time and can be “tuned” to different wavelengths. Since different gases absorb different wavelengths of light, a tunable laser could be used to detect the presence of numerous substances in the air or human breath.

Both of her research efforts rely on the use of special lasers called a quantum cascade lasers, which emit light in the mid-infrared region of the spectrum. Bentil’s adviser, electrical engineering professor Claire Gmachl, is the director of the National Science Foundation-funded Mid-Infrared Technologies for Health and the Environment (MIRTHE) center.

Bentil returns to Ghana this year under far different circumstances than her re-entry into the country nearly two decades ago. Her family moved from Ghana to Liberia in 1986 for her father to work as a professor at the country’s national university. In 1990, eight months after the Liberian Civil War began, the family escaped by walking some 30 miles on foot before boarding a crowded ship to Nigeria. They then spent a week in a Nigerian refugee camp before boarding a cargo ship back to Ghana.

After finishing high school in Ghana, Bentil completed a special five-year program to earn separate bachelor’s degrees in physics and electrical engineering from Bryn Mawr and Cal Tech, respectively.

Given her life experiences and interests, Bentil looked for a specific kind of graduate engineering program -- one that would allow her to perform cutting-edge research that could be used to address major societal issues.

“I realized that at Princeton there was an opportunity not only to do good research,” she said, “but to benefit from resources outside engineering, like the Woodrow Wilson School [of Public and International Affairs] to broaden my understanding of global issues and challenges.”

At Princeton, she is a member of the Society of Women Engineers and the Graduate Christian Fellowship. She also has been active in outreach events, including judging the New Jersey Science Olympiad, participating in the Science and Engineering Expo for middle school students and sharing her personal experiences with a group of refugee students visiting campus as part of an International Rescue Committee summer youth program.