D. Yafaev
On Spectral Properties of Translationally Invariant Magnetic Schr\"odinger Operators
(83K, latex)
ABSTRACT. We consider a class of translationally invariant magnetic fields such that the corresponding potential has a constant direction.
Our goal is to study basic spectral
properties of the Schr\"odinger operator ${\bf H}$ with such a potential. In particular, we show that the spectrum of ${\bf H}$ is
absolutely continuous and we find its location. Then we study the
long-time behaviour of solutions $\exp(-i {\bf H} t)f$ of the time dependent Schr\"odinger equation.
It turnes out that a quantum particle remains localized in the plane orthogonal to the direction of the potential. Its propagation in this direction is determined by group velocities. It is to a some extent similar to a evolution of a one-dimensional free particle but ``exits" to $+\infty$ and $-\infty$ might be essentially different.