#GWSEH Researcher Spotlight: Engineering at the Speed of Light

Professor Volker Sorger’s opto-electronic technologies are helping to create a smarter planet.

March 9, 2015

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Volker Sorger, a professor in the Department of Electrical and Computer Engineering, is investigating new ways to more efficiently power computers and smart phones. (William Atkins/GW Today)

This is the first in a GW Today series that features faculty from the Columbian College of Arts and Sciences and the School of Engineering and Applied Science who are conducting research with an impact in Science and Engineering Hall.

By Lauren Ingeno

Professor Volker Sorger is sprinting from his sixth-floor office in Science and Engineering Hall to the elevators around the corner. It’s the morning of the School of Engineering and Applied Science’s research showcase, and student presentations start in five minutes.  

“This is taking too long,” says Dr. Sorger to his colleague, who is also helping to judge the student competition. “Let’s take the stairs.”

In an instant, he’s gone. 

Dr. Sorger, an assistant professor in the George Washington University Department of Electrical and Computer Engineering, doesn’t like standing still. The fast-talking, German-born engineer prefers creating, testing, doing, particularly in the field of technical innovations.

In his lab, he and his research team are working in nanophotonics, a field that attempts to control light at the nanometer level—a space about 80,000 times smaller than the width of a human hair.

Why is “shrinking” light advantageous?

“You can make things a hell of a lot faster,” says Duncan, d’Hemecourt, a sophomore studying biomedical engineering who works in Dr. Sorger’s Nanophotonics Lab.

Miniaturizing lasers could, for instance, lead to much faster and more efficient computer chips or more sensitive biosensors for detecting diseases.

“In about 10 years the show is over. We will be using 100 percent of our power on data sharing if we continue with this trend. There will be no energy left for light, heating or anything else. So, we need to do something. We have to innovate quickly.”

But creating nano-scale, light-operated devices has proven difficult for scientists, since light has what is called a diffraction limit. It is impossible to fit light into areas smaller than half of its wavelength, according to currently accepted laws of physics.
Dr. Sorger, however, has defied the laws of classical physics.
In 2009, using a technique called plasmonics, he and a team of researchers at the University of California-Berkley were the first to create the world’s smallest semiconductor laser that operated well below the diffraction limit.
“Plasmonics has to do with how light and metals interact. It sort of ‘bends’ light in a unique way. So, using plasmonics, we were able to essentially beat physics and squeeze light into tiny spaces,” he says. “It was physically and fundamentally novel.”
Now, using this plasmonics technique, Dr. Sorger is designing an ultra-fast, electro-optic modulator, potentially capable of operating at a trillion times per second.
“That’s really, really fast,” he assures, as his eyes light up like a young boy’s on Christmas morning.
Modulators are the workhorses of today’s Internet. They convert data between the electronic domain into the optical domain to send the data around the globe. The modulator Dr. Sorger’s team is creating could revolutionize how computers operate and reduce the remarkable amount of power it takes to store and process digital information, he says.

“Imagine your computer or your smart phone running with light,” Dr. Sorger says. “This will be a leap forward in terms of performance and requires significantly less energy to do so.”

All of the data we transfer every day—by sending a Tweet, emailing photos or downloading movies—take up space in tens of thousands of data centers across the country. These centers, or digital warehouses, used roughly 2 percent of all electricity in the United States in 2010, according to a 2012 New York Times article. It turns out that the 2 percent is growing exponentially at a rate of 46 percent compounded annually, Dr. Sorger says.

“That means in about 10 years the show is over. We will be using 100 percent of our power on data sharing if we continue with this trend,” Dr. Sorger says. “There will be no energy left for light, heating or anything else. So, we need to do something. We have to innovate quickly.”

Teaching the Next Generation

To build the modulator and other nanodevices, Dr. Sorger will make use of the state-of-the-art core facilities housed in Science and Engineering Hall. The nanofabrication lab is a class 100 clean room, meaning the air is swept clean of contaminants like dust and hair, which could easily affect these fabricated, miniature experiments.

In the lab, near industry-level equipment—such as high-end tools for writing miniscule patterns and microscopes for viewing specimens down to atomistic resolutions—will allow his team to design, create and test his technologies in-house, rather than outsourcing projects to other universities or taking day-long trips to the National Institute of Standards and Technology in Maryland.

“It will be completely transformative for my group,” Dr. Sorger says.

He is equally excited for the building’s “teaching clean room,” a scaled-down version of the nanofabrication facility where undergraduates can learn about nanotechnology.

“I like teaching undergrads,” he says. “They have a fresh approach to science, full of excitement and curiosity.”

In contrast to the theoretical, lecture-based physics he learned as a university student in Germany, Dr. Sorger is a believer in emerging classroom techniques such as hands-on learning and the collaborative classroom models.

In the “Innovation and Technology” course he teaches (SEAS 6100), Dr. Sorger encourages his students to “think with their hands.” He assures them that failure can lead to discovery, citing Google X, Google’s semi-secret innovation lab. Students spend the semester developing an engineering solution or disruptive technology, resulting in culminating TED talk-style presentations.

“It’s not my goal to know the ‘result’ of each class beforehand. It’s more important to come together and use this momentum of multiple people being together to create something new,” he says. “A class should be almost like a jazz concert, not a symphony.”

His passion for teaching is equally evident to his students.

“He is fantastic at presenting his ideas and keeping people engaged,” Mr. d’Hemecourt says. “Every time you go and talk to him he has some new idea and is genuinely excited about it. That kind of motivation is infectious to others.”

Since joining GW’s ECE Department two years ago, Dr. Sorger has moved full speed ahead into multiple projects.

In addition to his roles as teacher, researcher and adviser, Dr. Sorger is designing a new minor to be offered jointly by SEAS and the School of Business, and he is running a new fellowship program for undergraduates, supported by a National Science Foundation grant. He is also chief technology officer at BitGrid, a startup company led by two GW seniors, who won three prizes at last year’s Business Plan Competition, and was a finalist in the southeast Cleantech Open.

And he doesn’t plan to slow down anytime soon.

“GW gives me a lot of possibilities. I can create new programs, explore innovative projects, and together with my colleagues, create timely curricula,” he says. “There is great support and a lot of momentum in SEAS.”