Quantum noise reduction in coupled oscillators

Exact solutions for the time evolution of a quantum linear harmonic oscillator coupled to a second one with quadratic self-interacting terms is obtained. As known in the literature the second oscillator exhibits the squeezing effect in its quadratures while the first one does not exhibit it in a coherent state, i.e., the eigenfunctions of the annihilation operator. It is shown that due to the coupling the squeezing effect contagions the first linear oscillator. Interesting features in these solutions, are observed as the so called collapse and revival phenomena, independent of the existence of anharmonicity in the second oscillator, as recently suggested in the literature. (author). 10 refs, 8 figs