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Publications associées (43)

Fermi surface determination from wavevector quantization in LaSrCuO films

Davor Pavuna, Claudia Cancellieri, Ping-Hui Lin

We have observed the wavevector quantization in LaSrCuO films thinner than 12 unit cells grown on SrTiO3 substrates. Low energy dispersions were determined in situ for different photon energies by angle resolved photoemission spectroscopy. From the wavevec ...

2008

Modulational instability in nonlinearity-managed optical media

Demetri Psaltis, Ye Pu

We investigate analytically, numerically, and experimentally the modulational instability in a layered, cubically nonlinear (Kerr) optical medium that consists of alternating layers of glass and air. We model this setting using a nonlinear Schrödinger (NLS ...

2007

SUPERFLIP– a computer program for the solution of crystal structures by charge flipping in arbitrary dimensions

Gervais Chapuis

SUPERFLIP is a computer program that can solve crystal structures from diffraction data using the recently developed charge-flipping algorithm. It can solve periodic structures, incommensurately modulated structures and quasicrystals from X-ray and neutron ...

2007

Modulational instability in a layered Kerr medium: Theory and experiment

Demetri Psaltis, Ye Pu

We present the first experimental investigation of modulational instability in a layered Kerr medium. The particularly interesting and appealing feature of our configuration, consisting of alternating glass-air layers, is the piecewise-constant nature of t ...

2006

Integral-equation analysis of 3-D metallic objects arranged in 2-D lattices using the Ewald transformation

Juan Ramon Mosig, Ivica Stevanovic, Frédéric Bongard, Pedro Crespo Valero, Katarina Blagovic

We present a space-domain integral-equation method for the analysis of periodic structures formed by three-dimensional metallic objects arranged in a general skewed two-dimensional lattice. The computation of the space-domain Green's function is accelerate ...

2006

Localization-dependent photoluminescence spectrum of biexcitons in semiconductor quantum wires

Benoît Marie Joseph Deveaud, Vincenzo Savona, Andrea Feltrin, Xiao Wang

We study exciton and biexciton spectra in disordered semiconductor quantum wires by means of nanophotoluminescence spectroscopy. We demonstrate a close link between the exciton localization length along the wire and the occurrence of a biexciton spectral l ...

2005

HRTEM simulation in determination of thickness and grain misorientation for hydroxyapatite crystals

Philippe Buffat, Pierre Stadelmann, Elena Suvorova Buffat

High-resolution transmission electron microscopy (HRTEM) and HRTEM simulation by the Bloch wave method (JEMS) are used to determine the structure and thickness of micro- and nanocrystals of biominerals and hydroxyapatite grown from aqueous solutions. It is ...

2004

sp(2)/sp(3) hybridization ratio in amorphous carbon from C 1s core-level shifts: X-ray photoelectron spectroscopy and first-principles calculation

Alfredo Pasquarello

Using a combined experimental and theoretical approach, we address C 1s core-level shifts in amorphous carbon. Experimental results are obtained by x-ray photoelectron spectroscopy (XPS) and electron-energy-loss spectroscopy (EELS) on thin-film samples of ...

2002

Electronic structure of solids with competing periodic potentials

Giorgio Margaritondo, Marco Grioni, Helmuth Berger, Luca Perfetti

When electrons are subject to a potential with two incommensurate periods, translational invariance is lost, and no periodic band structure is expected. However, model calculations based on nearly free one-dimensional electrons and experimental results fro ...

2000

Bonding, Structure, and Energetics of Gaseous E82+ and of Solid E8(AsF6)2 (E = S, Se)

Isabelle Dionne

The attempt to prep. hitherto unknown homopolyat. cations of sulfur by the reaction of elemental sulfur with blue S8(AsF6)2 in liq. SO2/SO2ClF, led to red (in transmitted light) crystals identified crystallog. as S8(AsF6)2. The X-ray structure of this salt ...

2000

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