Quantum Mechanics of a Particle with Two Magnetic Impurities
  A two-dimensional quantum mechanical system consisting of a particle coupled to two magnetic impurities of different strengths, in a harmonic potential, is considered. Topological boundary conditions at impurity locations imply that the wave functions are linear combinations of two-dimensional harmonics. A number of low-lying states are computed numerically, and the qualitative features of the spectrum are analyzed. 
Stefan Mashkevich (Univ. Kiev), Jan Myrheim (NTNU, Trondheim),   St\'ephane Ouvry (LPTMS, Orsay)