Electronic Journal of Differential Equations,
Vol. 2005(2005), No. 55, pp. 1-16.

Title: On the Aharonov-Casher formula for different self-adjoint 
       extensions of the Pauli operator with singular magnetic field
       
Author: Mikael Persson (Chalmers Univ. of Technology, Goteborg, Sweden)

Abstract: 
 Two different self-adjoint Pauli extensions describing a
 spin-1/2 two-dimensional quantum system with singular
 magnetic field are studied. An Aharonov-Casher type formula
 is proved for the maximal Pauli extension and the possibility
 of approximation of the two different self-adjoint extensions
  by operators with regular magnetic fields is investigated.
  
Submitted February 17, 2005. Published May 24, 2005.
Math Subject Classifications: 81Q10, 35Q40, 47F05.
Key Words: Schrodinger operators; spectral analysis.