Thank you for your helpful comment. Should I start sending emails right now? I have been admitted just two days ago. I don't know whether I should wait for hearing something about FA from the department or start contacting the ECE professors. Actually, I contacted some of them before applying. One said that my resume looks good but my background does not match his research interests and the other said that I have a good background but he has no vacant position. However, he encouraged me to apply in the hope that he could accept new students later. I don't know what to do!