I am shocked to learn about the death of Shoucheng Zhang. I express my sincere condolences to his family.
From 1981 on, I was a student in physics at the Freie Universität (FU) of Berlin (West), and I have vivid memories of Shoucheng Zhang, who studied there also, up to his Diplom (1983, with distinction), under the patronage of Robert Schrader. At FU, where professors and their assistants were outstanding (Peschel, Kleinert, Schrader, Truong, Helfrich in Physics; Berendt, Weimar, Waschbüsch in Mathematics), but where many students were enrolled for a number of extra-academic reasons, he was a fix point, and already at a very young age a role model for me. Shoucheng Zhang clearly belonged to the few people in this world who acquired learning effortlessly. He was so elegant, and also extremely cool: I still see him reading a (German) newspaper during class. With his soft voice, he spoke German fluently. I remember him as an avid reader of Feynman's Statistical Mechanics lecture notes. The library book was always either in his hands or in mine.
I was well aware when Shoucheng Zhang left Berlin for Stony Brook (I later left for Vienna, and then for Paris), and later met him in person only once again, in Les Houches (France), where he lectured on SU(5) symmetry breaking. Looking at the Mont Blanc, we exchanged about Berlin and the FU. Of course, I read many of his papers, and kept up with his work.
Again, I am saddened by Shoucheng Zhang's passing away. He had a lasting, formative, influence on my life.