# Hamiltonian for the spin-orbit coupling in spinor-notation

After some research I can't find a good source which explains how to write the Hamiltonian of a spin-orbit coupling in spinor notation.

The following notation is commonly used $$\hat H =\xi \hat L.\hat S$$ But I'm not sure how to relate this to spinor notation.

If someone could please explain how this is done I'd really appreciate it.