If nothing changed from the previous years, they should send an email to you within a couple of days on who your interviewers were. If you don't see it by the 3rd day, I would email or call the admissions committee to ask. If you remember who your interviewer is, you could always look up their emails, but you should be sure. One of my friends actually stayed late to write a handwritten thank you card to their interviewer and got in, but that's a little too extra for my taste.
Also, I'm a student here so feel free to ask me anything.