I am a Chinese student and recently get admitted by the MS ECE programs of UCSD(Photonics), UCLA(Physical Wave, Electronics) and UCSB(Electronics and Photonics). All of my research experiences are about photonics so I only applied for those tracks which are related to photonics, but I want to study in areas related to machine learning and AI in the future. I wonder if it's possible to change my tracks when I get enrolled in these schools above and which one will be the best choice to study machine learning. Thanks a lot!