Avoided crossing resonances: structural and dynamical aspects

We examine structural and dynamical properties of quantum resonances associated with an avoided crossing and identify the parameter shifts where these properties attain maximal or extreme values, first at a general level, and then for a two-level system coupled to a harmonic oscillator, of the type commonly found in quantum optics. Finally the results obtained are exemplified and applied to optimize the fidelity and speed of quantum gates in trapped ions.Comment: 4 pages, 1 figur

Links and analytic invariants of superisolated singularities

By using superisolated surface singularities whose link is a rational homology sphere we give counterexamples to some of the most important conjetures concernig invariants of normal surface singularities.Comment: Revised version, to appear in Journal of Algebraic Geometr

On piecewise isomorphism of some varieties

Two quasi-projective varieties are called piecewise isomorphic if they can be stratified into pairwise isomorphic strata. We show that the m-th symmetric power $S^m(C^n)$ of the complex affine space $C^n$ is piecewise isomorphic to $C^{mn}$ and the m-th symmetric power $S^m(CP^\infty)$ of the infinite dimensional complex projective space is piecewise isomorphic to the infinite dimensional Grassmannian $Gr(m,\infty)$

Efficient oxide phosphors for light upconversion; green emission from Yb3+ and Ho3+ co-doped Ln(2)BaZnO(5) (Ln = Y, Gd)

This is the author's accepted version of the article. The final published article can be found here: http://dx.doi.org/10.1039/C0JM01652