  The coherent states for a set of quadratic Hamiltonians in the trap regime
are constructed. A matrix technique which allows to identify directly the
creation and annihilation operators will be presented. Then, the coherent
states as simultaneous eigenstates of the annihilation operators will be
derived, and they are going to be compared with those attained through the
displacement operator method. The corresponding wave function will be found,
and a general procedure for obtaining several expected values involving the
canonical operators in these states will be described. The results will be
illustrated through the asymmetric Penning trap.
