A Scheme for Preparation of W-Type Entangled Coherent State of Three-Cavity Fields

郭裕, 匡乐满

Chun-Hua Yuan, Yong-Cheng Ou, Zhi‐Ming Zhang

We present an experimental scheme to prepare the three-cavity W -type entangled coherent state in the context of dispersive cavity quantum electrodynamics. The discussion of our scheme indicates that it can be realized by current technology.

Ma Song-She

A scheme was proposed to generate the W-type entangled coherent states of three-cavity fields, after comparing the differences between the discrete-variable quantum information and the continuous-variable quantum information and taking into account that coherent states were presently of practical use and readily available. The scheme was based on the degenerate Raman interaction of a Λ-type three-level atom with a single-mode field. Three identical cavities were in coherent states and three identical atoms shared a W-type entangled state initially. Let the three atoms interact with the three cavity fields respectively, selected a proper interaction time and detected the three atoms after exiting from their respective cavity. Then the three-cavity fields were projected onto a W-type entangled coherent states. During the atom-field interaction the atoms have no probability of being populated in the upper level, then the atomic spontaneous emissions could be neglected. Therefore, the coherence of the system might be better maintained. Based on current cavity quantum electrodynamics technique, the scheme could be realized experimentally. The W-type entangled coherent states generated was expected to be useful in the continuous-variable quantum information processing. The scheme was generalized to prepare the W-type entangled coherent states of n-cavity fields (n〉3).

Shi‐Biao Zheng

Saad Rfifi, Morad El-Baz

We establish a new model for realization of three qubit C-NOT gate operations between two Rydberg atoms and coherent Cavity field. To exploit this C-NOT realization, we enhance m any schemes for generation of GHZ-type and W-type entangled coherent state (ECS), to prepare n-cavities GHZ- type (ECS) and n-cavities W- type (ECS). Furthermore, we find the possibility of p reparing cluster entangled coherent states using the realized three qubit C-NOT gate. Our model compared with the references schemes generation is more efficient because of simplicity of detect ing coherent fields. Also, the rigidity of the model comes fro m the smaller interaction time needed to realize the three quantum entangled systems due to the proposed interaction.

X.-B. Zou, K. Pahlke, Wolfgang M. Mathis