We present the analysis of mathematical structure of SU(2) group, specifically the commutation relation between raising and lowering operators of the Morse oscillator. The relationship between the commutator of operators and other parameters of Morse oscillator is investigated. We show that the mathematical structure of operators which depends on the parameters of Morse oscillator may change our conventional expectation. The parameter space of Morse oscillator is visualized to scrutinize the mathematical relations that are related to the Morse oscillator. This parameter space is the space of possible parameter values that depend on the depth of the Morse potential well and other parameters. The algorithm that we present is also applicable to other quantum systems with certain modifications.
We present the analysis of mathematical structure of SU(2) group, specifically the commutation relation between raising and lowering operators of the Morse oscillator. The relationship between the commutator of operators and other parameters of Morse oscillator is investigated. We show that the mathematical structure of operators which depends on the parameters of Morse oscillator may change our conventional expectation. The parameter space of Morse oscillator is visualized to scrutinize the mathematical relations that are related to the Morse oscillator. This parameter space is the space of possible parameter values that depend on the depth of the Morse potential well and other parameters. The algorithm that we present is also applicable to other quantum systems with certain modifications.
A realization of the raising and lowering operators for the Morse potential is presented. We show that these operators satisfy the commutation relations for the SU(2) group. Closed analytical expressions are derived for the matrix elements of different functions such as 1/y and d/dy. The harmonic limit of the SU(2) operators is also studied. The transition probability between two eigenstates produced by a harmonic perturbation as a function of the operators [Formula: see text]±,0 is discussed. The average values of some observables in the coherent states |α > for the Morse potential are also calculated. PACS Nos.: 02.30+b, 03.65Fd, 42.50Ar, and 33.10Cs
The coherent states of the Morse potential that have been obtained earlier from supersymmetric quantum mechanics, are shown to be connected with the representations of the affine group of the real line and some of its extensions. This relation is similar to the one between the Heisenberg-Weyl group and the coherent states of the harmonic oscillator. The states that minimize the uncertainty product of the generators of the affine Lie algebra are shown to contain all the coherent states of the Morse oscillator plus the intelligent states of the Morse Hamiltonians with different shape parameter s . The representations of the central extension of the affine group denoted by G 0 and its further extension will be shown to define the phase space relevant to the problem by choosing an appropriate orbit of the coadjoint representation of . This allows one to construct a generalized Wigner function on this phase space, which is again essentially in the same relation with the affine group, as the ordinary Wigner function with the Heisenberg-Weyl group.
Using operators of the invariance group of their time-dependent Schr\"odinger equations it is shown that the bound states of Morse oscillators are bases for discrete nonunitary irreducible representations (non-UIRs) of the groups Sp(2,R), SU(1,1), and SO(2,1). Hermiticity requirements and the dependence of the group generators on the dynamical variables determine the operator of an isometry which connects these non-UIRs of the noncompact invariance groups to UIRs of the compact groups SU(2) and SO(3) that have been used as spectrum-generating groups for Morse systems.
The Morse oscillator, radial Coulomb and radial harmonic oscillator problems can be solved exactly using a variety of algebraic methods. These problems correspond to different realizations of the so(2,1) algebra and a comparison of the generators of the algebra may be used to identify mappings between each pair of systems. The resultant transition operators act as ladder, or energy changing, operators in the cases of the Coulomb and harmonic oscillator potentials, whereas they act as shift operators, acting at constant energy, in the case of the Morse potential. This is a consequence of the so(2,1) dynamical symmetry, whereby the Morse Hamiltonian is expressible solely in terms of the Casimir operator of the algebra. An alternative algebraic approach, the use of the method of supersymmetric quantum mechanics, or factorization, produces in each case a set of shift operators. Relations between the various ladder and shift operators may be identified by means of the appropriate mappings, and these results can be generalized so as to relate the one dimensional Morse oscillator to the radial Coulomb and radial harmonic oscillator potentials involving an arbitrary number of angular dimensions.