Abstract:
We consider the two-dimensional Shrödinger operator $\widehat H_B+V$ with a homogeneous
magnetic field $B\in {\mathbb R}$ and with an electric potential $V$ which belongs to the space $L^p_{\Lambda }
({\mathbb R}^2;{\mathbb R})$ of $\Lambda $ -periodic real-valued functions from the space $L^p_{\mathrm {loc}}
({\mathbb R}^2)$, $p>1$. The magnetic field $B$ is supposed to have the rational flux $\eta =(2\pi )^{-1}Bv(K)
\in {\mathbb Q}$ where $v(K)$ denotes the area of the elementary cell $K$ of the period lattice $\Lambda \subset
{\mathbb R}^2$. Given $p>1$ and the period lattice $\Lambda $, we prove that in the Banach space $(L^p_{\Lambda }
({\mathbb R}^2;\mathbb R),\| \cdot \| _{L^p(K)})$ there exists a typical set $\mathcal O$ in the sense of Baire (which
contains a dense $G_{\delta}$ -set) such that the spectrum of the operator $\widehat H_B+V$ is absolutely continuous for any
electric potential $V\in {\mathcal O}$ and for any homogeneous magnetic field $B$ with the rational flux $\eta \in
{\mathbb Q}$.
Keywords:two-dimensional Schrödinger operator, periodic electric potential, homogeneous magnetic field, spectrum.