Eigenvalue bounds for two-dimensional magnetic Schroedinger operators
  We prove that the number of negative eigenvalues of two-dimensional magnetic Schroedinger operators is bounded from above by the strength of the corresponding electric potential. Such estimates fail in the absence of a magnetic field. We also show how the corresponding upper bounds depend on the properties of the magnetic field and discuss their connection with Hardy-type inequalities. 
Hynek Kovarik
math.SP math-ph math.MP