Estado de vácuo comprimido para a luz: um questionamento sobre sua construção experimental

Abstract

Coherent states are usually used to describe the state of a laser field in experiments for the generation and detection of squeezed states, in particular for the squeezed vacuum state. Nevertheless, the state of a laser field is better described by a statistical mixture of coherent states with random phases or, similarly, by a statistical mixture of Fock states.In this sense, the present works aim was to describe the experiment of generation of the squeezed vacuum state without using coherent states to describe the laser field. For the purpose of a first analysis, the state of the laser light was considered to be in a Fock state. Subsequently, for a more realistic description, a statistical mixture of Fock states is considered to describe the output state of the laser. From the correspondence between a statistical mixture of coherent states with random phases and a statistical mixture of Fock states, it is possible to obtain the experimental results without actually generating squeezedstates, since squeezing in a specific quadrature is not obtained due to the randomness of the laser field phase. This raises a question whether, in fact, the experimental generation of the squeezed vacuum states has already occurred.