I would suggest starting from the basics of quantum physics if you don't already have a solid foundation. MIT has several excellent courses on the subject [1-4]. The first two are the same course, but taught by different professors with slightly different curriculum.

[1] https://ocw.mit.edu/courses/physics/8-04-quantum-physics-i-s...

[2] https://ocw.mit.edu/courses/physics/8-04-quantum-physics-i-s...

[3] https://ocw.mit.edu/courses/physics/8-05-quantum-physics-ii-...

[4] https://ocw.mit.edu/courses/physics/8-06-quantum-physics-iii...