We propose a new determination of the confinement-deconfinement transition by using the imaginary
chemical potential. The imaginary chemical potential can be interpreted as the AharonovBohm
phase and then an analogy of the topological-order suggests that the Roberge-Weiss endpoint
would define the deconfinement temperature. Based on the topological property, we can
construct a new quantity which describes the confinement-deconfinement transition. This quantity
is defined as the integral of the quark number susceptibility along the closed loop of θ where
θ is the dimensionless imaginary chemical potential. Expected behavior of it at finite temperature
is discussed and its asymptotic behaviors are shown.