On the spectrum of the Kronig-Penney model in a constant electric field

Rupert L. Frank, Simon Larson

We are interested in the nature of the spectrum of the one-dimensional Schrödinger operator $$ - \frac{d^2}{dx^2}-Fx + \sum_{n \in \mathbb{Z}}g_n δ(x-n) \qquad\text{in } L^2(\mathb…