We analyze the entanglement between two matter modes in a hybrid quantum system consisting of a microcavity, a quantum well, and a mechanical oscillator. Although the exciton mode in the quantum well and the mechanical oscillator are initially uncoupled, their interaction through the microcavity field results in an indirect exciton-mode–mechanical-mode coupling. We show that this coupling is a ...

It has been shown that there exist Bell inequalities constructed from symmetric oneand two-body correlations that are violated by certain quantum states involving any number of particles. However, the properties of such Bell inequalities have not been completely characterised. In this study, we determine the behaviour of various classes of entangled states with respect to these inequalities. It...

We examine the prospect of demonstrating Einstein-Podolsky-Rosen (EPR) entanglement for massive particles using spin-changing collisions in a spinor Bose-Einstein condensate. Such a demonstration has recently been attempted by Gross et al. [Nature (London) 480, 219 (2011)] using a condensate of 87Rb atoms trapped in an optical lattice potential. For the condensate initially prepared in the (F,m...

With the rapid growth of quantum technologies, knowing the fundamental characteristics of quantum systems and protocols is essential for their effective implementation. A particular communication setting that has received increased focus is related to quantum key distribution and distributed quantum computation. In this setting, a quantum channel connects a sender to a receiver, and their goal ...

In the present study, temporal behavior of entanglement between photonic binomial distributions and a two-level atom in a leaky cavity, in equilibrium with the environment at a temperature T, is studied. In this regard, the master equation is solved in the secular approximation for the density matrix, when the initial photonic distribution is binomial, while the atomic states obey the Boltzmann...

the time evaluation of quantum entropy in a four-level double- type atomic system is theoretically investigated. quantum entanglement of the atom and its spontaneous emission fields is then discussed via quantum entropy. it is found that the degree of entanglement can be increased by the quantum interference induced by spontaneous emission. the phase dependence of the atom-field entanglement is...

When a physical system is put in contact with a very large thermal bath, it undergoes a dissipative (i.e., an apparently irreversible) process that leads to thermal equilibrium. This dynamical process can be described fully within quantum physics, involving only unitary, therefore reversible, maps. The information, initially present in the system, is not erased, but is diluted in the bath becau...