On continuous spectrum of magnetic Schr\'odinger operators on periodic discrete graphs

Autor: Korotyaev, Evgeny, Saburova, Natalia
Rok vydání: 2021
Předmět:
Druh dokumentu: Working Paper
Popis: We consider Schr\"odinger operators with periodic electric and magnetic potentials on periodic discrete graphs. The spectrum of such operators consists of an absolutely continuous (a.c.) part (a union of a finite number of non-degenerate bands) and a finite number of eigenvalues of infinite multiplicity. We prove the following results: 1) the a.c. spectrum of the magnetic Schr\"odinger operators is empty for specific graphs and magnetic fields; 2) we obtain necessary and sufficient conditions under which the a.c. spectrum of the magnetic Schr\"odinger operators is empty; 3) the spectrum of the magnetic Schr\"odinger operator with each magnetic potential $t\alpha$, where $t$ is a coupling constant, has an a.c. component for all except finitely many $t$ from any bounded interval.
Comment: 12 pages, 1 figure
Databáze: arXiv