A Study of the non-classical states of a cavity field

S. Deléglise, I. Dotsenko, C. Sayrin +4 more

Dotsenko, Bernu, S. Deléglise +4 more

M. Brune

Bastian Hacker, Severin Daiss, Stephan Welte +3 more

Anneswa Paul, Upendra Harbola

Abstract Electromagnetic field states in optical cavities can show classical-nonclassical transition due to interaction with matter in the cavity. We analyze non-classicality in cavity-field state using negativity in its phase-space (quasi) distribution. We show that induced coherences in the cavity-state always enhance the non-classical nature of the field. The presence of vacuum state, on the other hand, diminishes the non-classicality as it represents a classical state with zero negativity. For weak cavity-field, the effect of vacuum state increases as the photon-number fluctuations are increased. These results have direct applications in areas, such as quantum metrology and cavity-induced chemistry, where non-classicality of cavity-field states is known to be an important resource.

Jorge Andres Anaya-Contreras, Arturo Zúñiga-Segundo, Francisco Soto +1 more

The creation of non-classical states of light is an interesting problem, that we solve sending atoms through an optical cavity. We show that it is possible to add or subtract many photons from a cavity field by interacting it resonantly with a two-level atom. The atom, after entangling with the field inside the cavity and exiting it, may be measured in one of the Schmidt states, producing a multiphoton process (in the sense that can add or annihilate more photons than a single transition allows), i.e. adding or subtracting several photons from the cavity field. By plotting the quadratures and the Husimi Q-function, we also show that the non-classical state produced by such measurements is a squeezed state.