Leading chipmaking engineer Xu Zhenpeng said the United States no longer offered the freedom that researchers once expected – a key reason for his decision to continue his work in China. Xu, who joined Shanghai Jiao Tong University (SJTU) as a tenure-track assistant professor in January, left behind a team leadership role at Atomic Semi, a California start-up with high-profile backers that included OpenAI’s venture fund. Before his departure, Xu led a team that was developing a new kind of...