SU(1,1) COHERENT STATES DEFINED VIA A MINIMUM-UNCERTAINTY PRODUCT ANDAN EQUALITY OF QUADRATURE VARIANCES

The coherent states of a Hamiltonian linear in SU(1,1) operators are c onstructed by defining them, in analogy with the harmonic-oscillator c oherent states, as the minimum-uncertainty states with equal variance in two observables. The proposed approach is thus based on a physical characteristic of the harmonic-oscillator coherent states which is in contrast with the existing ones which rely on the generalization of th e mathematical methods used for constructing the harmonic-oscillator c oherent states. The set of states obtained by following the proposed m ethod contains not only the known SU(1,1) coherent states but also a d ifferent class of states.