Mechanical vs electronics in engineering?

I am physics graduate. I advise you to take mech eng if you are interested in Robotronics. There are some uni offering B. Tech in Mechatronics which deal with robotronics. If you are interested in quantum and particle physics then you have to take BSc in physics. There are some universities that offer PhD in physics even if you do B. Tech but for that you need to study well also from a good college/university.