Generating maximally entangled distant pair in invariant stratification spin networks

In this paper we study the generation of Bell states between distant vertices in a permanently coupled quantum spin network, interacting via invariant stratification graphs. To begin with we establish a class of upper bounds over achievable entanglement between the reference site and various vertices. We observe that the maximum of these upper bounds is 1 e-bit. We conclude that the reference site can generate a Bell state with a vertex if the corresponding upper bound of the vertex is 1 e-bit. Thus for generation of a Bell state this upper bound must be saturated. Taking this into account, we obtain the characteristic constraint of the proper graphs. We introduce a special class of antipodal invariant stratification graphs, which is called reflective, whereas the antipode vertex obeys the characteristic constraint. We also show that the antipodal association scheme graphs are reflective so Bell states can be generated between the antipodal vertices. Moreover we observe that in such graphs the proper Hamiltonian that enables creation of Bell state is the Heisenberg interaction between vertex pairs.Comment: 14 pages 2 figure

Generating GHZ state in 2m-qubit spin network

We consider a pure 2m-qubit initial state to evolve under a particular quantum me- chanical spin Hamiltonian, which can be written in terms of the adjacency matrix of the Johnson network J(2m;m). Then, by using some techniques such as spectral dis- tribution and stratification associated with the graphs, employed in [1, 2], a maximally entangled GHZ state is generated between the antipodes of the network. In fact, an explicit formula is given for the suitable coupling strengths of the hamiltonian, so that a maximally entangled state can be generated between antipodes of the network. By using some known multipartite entanglement measures, the amount of the entanglement of the final evolved state is calculated, and finally two examples of four qubit and six qubit states are considered in details.Comment: 22 page

Theoretical study of quantum emitters in two-dimensional silicon carbide monolayers

The electronic and optical features of some potential single-photon sources in two-dimensional silicon carbide monolayers is studied via ab initio calculations and group theory analyses. A few point defects in three charge states (negative, positive, and neutral) are considered. By applying performance criteria, Stone-Wales defects without and with combination of antisite defects are studied in detail. The formation energy calculations reveal that neutral and positive charge states of these defects are stable. We compute the zero-phonon-line energy, the Huang-Rhys (HR) factor, and the photoluminescence spectrum for the available transitions in different charge states. The calculated HR values and the related Debye-Waller factors guarantee that the Stone-Wales defects have a high potential of performing as a promising single-photon emitter.Peer reviewe

Kinetics and oxygen dependence of uptake of nanozeolites by human glioblastoma cells

CERVOXYNational audienc

Synthesis of core-shell magnetic nanoparticles containing ultra-small domains of silicalite-1

International audienc

Synthesis of core-shell magnetic nanoparticles containing ultra-small domains of silicalite-1

International audienc

Kinetics and oxygen dependence of uptake of nanozeolites by human glioblastoma cells

CERVOXYNational audienc