The forefront of contemporary advances in physics lies in the submicroscopic regime, whether it be in atomic, nuclear, condensed-matter, plasma, or particle physics, or in quantum optics, or even in the study of stellar structure. All are based upon quantum theory (i.e., quantum mechanics and quantum field theory) and relativity, which together form the theoretical foundations of modern physics. Many ... Read more

The exciting new features of entanglement are burgeoning with revolutionary new advances in the areas of quantum communication, quantum information processing and quantum computing. We review recent theoretical studies and applications of pure and mixed states entanglement of trapped ions interacting with a laser field. After an introduction to the basic concepts of traditional entanglement measures and methodology, the main ... Read more

We study the uncertainty relations between photon number and canonical phase of a multilevel system. All the relevant quantities can be sampled directly from the measured phase-dependent quadrature distribution. Some comments are made on the extension of these relations to the case where the Hilbert space is of infinite dimension. We describe its theoretical basis and discuss its practical relevance, ... Read more