The basic invariants and stable squeezed states

P. L. Knight, Vladimír Bužek

Sibel Başkal, Young S Kim, Marilyn E. Noz

Tiezheng Qian, Jing-Bo Xu, Xiao-Chun Gao

A new concept of the basic invariants is introduced. With the help of the basic invariants, new high-n squeezed states of the time-dependent harmonic oscillator are constructed. From the basic invariants, the author also finds a general form of invariants which has not been seen thus far in the literature.

A. D. Jannussis, Vasileios Bartzis

Fan Hong-Yi, Haider R. Zaidi

The conditions for the existence of a time-dependent invariant for the general quadratic Hamiltonian are investigated. A general expression for such an invariant is obtained, and it is shown that the stable squeezed states are eigenstates of this invariant.

Yu You

The basic invariants and the general forms of the invariants for a driven harmonic oscillator with time dependent frequency are studied. With the help of the basic invariant, the squeezed states and squeezed number states for this time-dependent system are also constructed.