I would recommend bringing and nice black portfolio, in it have 2 pens, paper to take notes on, a paper with questions you wish to ask the faculty (shows preparedness), copy of resume. I personally would not bring pre-written thank you notes, this may come off as odd and very kiss ass. A good alternative is to ask for their business card after the interview (most professors have them). This way you can email them a thank you and mention something unique you both discussed during the interview. This will showcase gratitude while eliminating the essences of kissing ass just to get into a program.