A note on the geometric phase in adiabatic approximation
  The adiabatic theorem shows that the instantaneous eigenstate is a good approximation of the exact solution for a quantum system in adiabatic evolution. One may therefore expect that the geometric phase calculated by using the eigenstate should be also a good approximation of exact geometric phase. However, we find that the former phase may differ appreciably from the latter if the evolution time is large enough. 
D. M. Tong, K. Singh, L. C. Kwek, and C. H. Oh