Valley degrees of freedom
Multiple conduction-band minima can create additional low-energy states.
$$\Delta_v=E_{v,+}-E_{v,-}$$
Physical intuition
Multiple conduction-band minima can create additional low-energy states.
Deep dive: physical mechanism
Atomically sharp interfaces mix valley states and determine valley splitting.
What is measured experimentally?
Magnetospectroscopy and pulsed spectroscopy resolve valley excitations.
Assumptions, noise and limitations
Valley splitting is sensitive to interface steps and electric field.
Research and simulation exercise
Model a two-valley avoided crossing.
Connect the ideas
Explore the chapter overview, learning path, and references.