PhD in Mathematical Physics
It depends on what courses you end up taking as part of your physics minor. Mathematical physics leans heavily on Lagrangian and Hamiltonian mechanics, quantum mechanics, statistical mechanics, and electrodynamics.

I don't know how many credits you have available for your minor and what the requirements are in your university to take those courses. At the very least, make sure that you have taken both classical mechanics and quantum mechanics. Your math background in real and complex analysis will put you in great shape to learn the formalisms of the other theories.

Good luck!