Research Interest in physics (Transferring would be good idea?) I'm a first year PhD student at a university in the USA. Still I haven't finished my first semester. After I come here, I feel right now, I like  a different  research field (based on job application and doing empirical research). The problem is that, there is only two professors who do that type of research work in my department. One of the professor doesn't have a good reputation doing research work and another one's  review is not good (I heard his from previous students. He is very rude sometimes, this scared me a lot). He is very furious if his students can't satisfy his expectations. Therefore I don't have wish to work under his supervision. 

I have two options right now, 1. changing research field and 2. finding another university related to my research interest. 

Please note that I have not taken the first qualifying exam and even my first semester core courses haven't finished yet. The university gives the MS certificate if anyone satisfies the requirement of MS.  

I have received suggestion from one of the PhD student which is: I should take the physics GRE to increase my score and apply this upcoming fall. If I get admission, I can inform the International office that I will leave. 

This suggestion didn't seem good to me because my department may take this in negative way, as I will require a recommendation letter. 

What's your suggestions in this case? Should I wait more and talk to the professors after my qualifying exam regarding my research interest.
I'll start off by saying that transferring is not unheard of, but also definitely not common.

As a first year, you can't have gotten that far into your studies given that it is still September. In general, in physics at least, it's uncommon for someone to go to grad school with a very specific topic in mind and then follow through on it through dissertation. You'll move around as you naturally move through problems of funding, finding an advisor, and just as your interests evolve. The professor and topic you start working with doesn't necessarily have to be your advisor and your dissertation topic.

I would recommend talking more to the professors who do what you might be interested in, and expanding your search. It's not uncommon to only have one or two professors working in a specific field at a department, but if they are unappealing you might find another professor you like works on something similar. For that matter, when talking to other professors, you might find that you really are interested in what they do and want to work on it.

If that doesn't work out, you CAN apply to transfer. However, as other questions have noted previously, it is an uphill battle. You'll need a convincing reason (WITHOUT sounding bitter or negative) and a very strong application package. Just applying doesn't commit you, but I would consider that a last resort only after you have tried everything else.