No, superconductor physicist Xiaoxing Xi should not have been arrested. Superconductor physicist Xiaoxing Xi was arrested at the height of his career because the United States government believed that he was sharing proprietary information with China. Xiaoxing Xi is a citizen of China who was living in the United States while doing physics work. Some of his knowledge was bound to be put to use in China.
Though economic espionage and trade secrets theft are among the primary threats facing the United States, and China is involved in many of them. Yet a number of cases have also been improperly targeted. President Obama and Chinese President Xi Jinping, have vowed in an agreement not to target each other’s companies.
I think the federal prosecutors who supervised this case are even more blame worthy than the FBI for ruining this man's career and reputation. He should sue the US government for violations of his civil right as US citizen. This is clearly an intimidation, discrimination and oppression of USA federal government against an ethnic minority.
Xiaoxing Xi, a physicist specializing in superconductor research, was arrested in 2015 when the US government misunderstood research schematics Xi sent to colleagues in China. The Department of Justice believed that the schematics were related to superconductor research. However, the schematics were for a collaborative invention with the recipient. The Department of Justice dropped charges when they realized their mistake. However, they should not have immediately arrested Xi without confirming their evidence.