Abstract We studied the dynamics of the entanglement for two electron atoms as a ”bipartite” quantum system with continuous degrees of freedom. We analyze in particular the time evolution of initial states created from a superposition of the eigenstates of the two-electron Hamiltonian with variable nuclear charge Z. We find that the pairwise entanglement for the two electrons propagate in a way...

By recording low-noise energy-dispersive x-ray spectroscopy maps from crystalline specimens using aberration-corrected scanning transmission electron microscopy, it is possible to probe core-level electron orbitals in real space. Both the 1s and 2p orbitals of Sr and Ti atoms in SrTiO3 are probed, and their projected excitation potentials are determined. This paper also demonstrates experimenta...

In a recent paper, eight semileptonic parameters were defined to specify the most general Lorentz-invariant spin correlation functions for tau semileptonic decays. The parameters were physically defined in terms of tau-decay partial-width intensities for polarized final states. This paper studies how these parameters can be simply measured at a tau/charm factory with longitudinally polarized be...

We discuss the measured partial width of the pseudoscalar charmonium state ηc into two photons. Predictions from potential models are examined and compared with experimental values. Including radiative corrections, it is found that present measurements are compatible both with a QCD type potential and with a static Coulomb potential. The latter is then used to give an estimate on the ηb decay i...

We study the magnetic excitations of a square lattice spin-ice recently produced in an artificial form, as an array of nanoscale magnets. Our analysis, based upon the dipolar interaction between the nanomagnetic islands, correctly reproduces the ground-state observed experimentally. In addition, we find magnetic monopole-like excitations effectively interacting by means of the usual Coulombic p...

We discuss the implications of charged lepton energy cut to the hadronic invariant mass spectrum in charmless semileptonic B decays. Charged-lepton energy cut is inevitable in order to remove secondary leptonic events such as b → c, τ → l, and to identify the chaged leptons at detectors experimentally. We consider three possible lepton energy cuts, Ecuts l = 0.6, 1.5, 2.3 GeV, and found that wi...