Nonlinear Quantum Optical Springs and Their Nonclassical Properties
  The original idea of quantum optical spring arises from the requirement of quantization of the frequency of oscillations in the Hamiltonian of harmonic oscillator. This purpose is achieved by considering a spring whose constant (and so its frequency) depends on the quantum states of another system. Recently, it is realized that by the assumption of frequency modulation of $\omega$ to $\omega\sqrt{1+\mu a^\dagger a}$ the mentioned idea can be established. In the present paper, we generalize the approach of quantum optical spring with particular attention to the {\it dependence of frequency to the intensity of radiation field} that {\it naturally} observes in the {\it nonlinear coherent states}, from which we arrive at a physical system has been called by us as {\it nonlinear quantum optical spring}. Then, after the introduction of the generalized Hamiltonian of nonlinear quantum optical spring and it's solution, we will investigate the nonclassical properties of the obtained states. Specially, typical collapse and revival in the distribution functions and squeezing parameters, as particular quantum features, will be revealed. 
M.J. Faghihi and M.K. Tavassoly
quant-ph