TL;DR: In this article, a quantum concentration scheme for atomic entangled states is presented, which is insensitive to the cavity field states and the cavity decay and can be implemented by the present cavity QED techniques.
TL;DR: The concept of quantum concentration for the liquid phase of elements was introduced in this article, which indicates the number of possible states of atoms per unit volume A simplified thermodynamic energy model for a solid-liquid phase transition is used to define the quantum concentration of the liquids values of liquid phases of most of elements were calculated and analyzed.
TL;DR: In this article, a scheme of quantum concentration for unknown atomic entangled states via cavity QED is proposed, where the cavity is only virtually excited during the preparation and the joint measurement of quantum states, thus, the scheme is insensitive to the cavity field states and the cavity decay.
Abstract: A scheme of quantum concentration for unknown atomic entangled states via cavity QED is proposed. During the preparation and the joint measurement of quantum states, the cavity is only virtually excited; thus, the scheme is insensitive to the cavity field states and the cavity decay. In the meanwhile, our setup also provides a demonstration of a quantum repeater in cavity QED in principle.