Out of this World: OU Professor Contributes to the Technology Used in the Exploration of Mars
On Feb. 21, 2021, NASA’s largest, most advanced rover – Mars Perseverance – successfully landed on the surface of the Mars after a 203-day, 292.5-million-mile journey. Its mission is to study the geology and climate of Mars, and search for evidence of microbes that may have lived on Mars. The latest rover builds on the success of its predecessor, the Curiosity rover, which landed on Mars in 2012.
Rui Q. Yang, a professor in the University of Oklahoma School of Electrical and Computer Engineering, played a vital role in developing the interband cascade laser (ICL), which enabled the Curiosity rover to characterize the presence of methane in the atmosphere of Mars.
The interband cascade laser emits infrared light at a specific wavelength that is strongly absorbed by methane molecules. The amount of light absorption is a measure of the concentration of methane in the atmosphere. From measurements conducted from 2012 until now, a seasonal variation in the concentration of methane was observed. The Mars Perseverance will investigate whether the source of methane is a geophysical process or a sign of microbial life.
Before coming to OU in 2007, Yang served as a task manager at the California Institute of Technology’s Jet Propulsion Laboratory (JPL), in Pasadena, California. He was also a principal member of the engineering staff and led the development of a specialized interband cascade laser for the mission to Mars.
“NASA has a large interest in knowing whether there has been life beyond Earth,” Yang said. “They want to study whether there is an environment that is suitable for life on Mars and whether there will be a suitable environment for life on Mars in the future.”
The idea behind the invention of the interband cascade laser was proposed by Yang in 1994 while he was working at the School of Electrical and Computer Engineering at the University of Toronto in Canada. After about three years of continued research by him and his collaborators, the lasers were demonstrated in early 1997 by a collaboration between the University of Houston and Sandia National Laboratories. Yang then moved to the East Coast to continue his development of the lasers before arriving at JPL in 2001.
“After I moved to JPL, I continued to develop the technologies mainly for NASA applications,” Yang said. “We received positive feedback on the lasers after years of development and their use in flight instruments on balloon and airplane, and in 2006 we were given the task to develop the lasers for detecting methane, a molecule whose presence might indicate life on Mars.”
Before Yang’s invention of the interband cascade laser, there were no mid-infrared technologies suitable for space applications as other lasers could not operate effectively at ambient temperatures. NASA faced a real challenge to have a laser meet their requirements, and though NASA does not typically adapt technology that has not already been proven to be successful, Yang’s ICL was the only piece of technology that came close to what NASA wanted.
“The foundation to these lasers is all physics, especially in quantum mechanics,” Yang explained. “Without physics, I could not conceive the concept of interband cascade lasers, and I find it important for young generations of engineers to have a good understanding and knowledge across different disciplines, including quantum physics. I have benefited from both physics and engineering.”
As the news of JPL and NASA’s Mars exploration continues to pique the interests of people around the world, Yang spends his time enriching his students’ lives through his lectures and laboratory research at the University of Oklahoma. Through his group’s various projects, one thing remains a constant goal – develop new ideas and innovations that have potential for application and harvest the courage to explore the unknown world.
“One of the reasons I came to OU was because I had interest in having more interaction with students,” Yang said. “We are continuing to develop interband cascade lasers using a different approach, and we’ve also developed other types of devices based on interband cascade structures that we demonstrate here at OU.”
Yang and his group have demonstrated the world’s first interband cascade lasers with plasmon waveguides, which allow operation across a wide mid-infrared wavelength range beyond the conventional boundary. They have also demonstrated interband cascade photodetectors and interband cascade photovoltaic devices for energy conversion. They have established and remain in fruitful collaboration with other researchers from different institutions across the nation, particularly with Prof. Santos’s group in Physics at OU.
With technology continuing to evolve, and institutions like NASA and JPL striving to explore life beyond Earth, Yang and his group remain focused on the development of interband cascade lasers along with research in engineering physics and semiconductor quantum structures and devices.
“At universities, we like to focus on developing new ideas that have more potential for applications,” Yang said. “There are now other groups in the world following our approach, and that’s something we’re proud of here at OU.”
Additional Information on Rui Yang
In 2018, Yang received the Aaron Kressel Award “for inventions of the mid-infrared inter-band cascade laser, and its advancement along with related devices for applications.” This award recognizes those individuals who have made important contributions to optoelectronic device technology, which in turn have led to the development of new systems enabling services. This award was presented to Yang at the IEEE Photonics Conference Awards Banquet.
By Madysson Morris
Article Published: Wednesday, March 10, 2021