The chairman of Temple University's physics department sought prestigious appointments in China in exchange for providing data on a device invented by a U.S. firm and offered to make the country a leader in the field of superconductivity, federal prosecutors said.

Xi Xiaoxing, 47, appeared in U.S. District Court Thursday on four counts of wire fraud. The naturalized U.S. citizen who was born in China was released on $100,000 bond. It wasn't immediately known if he has an attorney.

Prosecutors said Xi took a sabbatical in 2002 to work with a U.S. company that developed a superconducting device that uses a thin film containing magnesium diboride. Researchers have found that magnesium diboride can conduct electricity at high temperatures, and Xi helped develop high-quality thin films.

He was awarded a grant in 2004 from the U.S. Department of Defense to purchase the device to use for research, but prosecutors say he then "exploited it for the benefit of third parties in China, including government entities" by sharing it and the technology behind it with the help of his post-doctoral students from China.

Xi also offered to build a world-class thin film laboratory in China, according to emails detailed by prosecutors.

The name of the U.S. firm isn't included in the indictment.

Xi joined Temple in 2009 and previously was a professor at Penn State University, according to his online faculty profile at Temple. He received his doctorate in physics from China's Peking University in 1987.