Valley–orbit coupling
Interface disorder can hybridize valley and orbital states.
$$H_v=\frac{\Delta_v}{2}\tau_z+t_v\tau_x$$
Physical intuition
Interface disorder can hybridize valley and orbital states.
Deep dive: physical mechanism
Valley mixing changes excited-state spectra and can create leakage pathways.
What is measured experimentally?
Avoided crossings reveal coupling strengths.
Assumptions, noise and limitations
The two-level valley approximation may fail near orbital resonances.
Research and simulation exercise
Sweep detuning through a valley anticrossing.
Connect the ideas
Explore the chapter overview, learning path, and references.