Congratulations! I used to live in Indiana, and I've been to the IUPUI campus several times for various reasons. I won't claim that it's really a top-notch school, but the great thing about graduate programs is that it doesn't matter very much where you are - it's who you meet there, and whether they're doing work that you find interesting, that matters. Do you have an adviser yet, and do you know of faculty you want to work with? It's very important that you establish a connection early on.
I was a physics major in college, and I was briefly in a graduate program in physics last year. I didn't continue with it because I decided I'd rather learn about biological systems - they're incredibly complex, but we're finally starting to truly understand them, and it's really interesting to me. I also managed to find a very good adviser with a biophysics background who was interested in working with me, so I switched programs. (there was also a brief interlude in a teaching program - it's been a strange year...)
But I know enough about physics to know that the area you want to study is really interesting. A professor I worked with as an undergrad did his postdoc at JILA at the University of Colorado and did a lot of work with Bose-Einstein condensates and the like. It's cool stuff, if you'll pardon the pun.
Finally, since it sounds like you're going to be a TA, how good is your spoken English, and how do you feel about teaching? One thing I'll warn you about is that American students tend to have terrible physical science backgrounds, and a lot of people who take intro physics classes are only there because they have to take it (as premeds and whatnot). They may need a lot of help from you. But it's worth it to see people understand things that they never dreamed they could understand.