Concept

Relation de dispersion

Publications associées (220)

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

Spin-orbit split two-dimensional electron gas with tunable Rashba and Fermi energy

Klaus Kern, Marco Grioni, Luca Moreschini, Daniela Pacilè

We demonstrate that it is possible to tune the Rashba energy, introduced by a strong spin-orbit splitting, and the Fermi energy in a two-dimensional electron gas by a controlled change of stoichiometry in an artificial surface alloy. In the BixPb1-x/Ag(111 ...

2008

Excitation energy map of high-energy dispersion anomalies in cuprates

Helmuth Berger

The anomalous high-energy dispersion of the conductance band in the high-T-c superconductor Bi(Pb)(2)Sr2CaCu2O8+delta (Pb-Bi2212) has been extensively mapped by angle-resolved photoemission spectroscopy as a function of excitation energy in the range from ...

2008

Metastability of fcc-related Si-N phases

The phenomenon of superhardening in TiN/SiNx nanocomposites and the prediction of extreme hardness in bulk gamma-Si3N4 have attracted a large interest to this material system. Attempts to explain the experimental findings by means of first-principles calcu ...

2008

Redistribution of pump power and impairments in gain-equalized distributed fiber Raman amplifiers due to four-wave mixing and parametric amplification

Marcelo Alfonso Soto Hernandez

In this work, by using a comprehensive numerical model which rigorously describes the interaction between stimulated Raman scattering (SRS) and four-wave mixing (FWM), we verify that FWM processes, including depletion and parametric gain, generate a redist ...

2008

Dispersion properties of silicon nanophotonic waveguides investigated with Fourier optics

Romuald Houdré, Nicolas Le Thomas, Jana Jágerská

We experimentally investigate the dispersion relation of silicon-on-insulator waveguides in the 1.5 mu m wavelength range by using a technique based on far-field Fourier-space imaging. The phase information of the propagating modes is transferred into the ...

Optical Society of America2007

Grating-assisted superresolution of slow waves in Fourier space

Romuald Houdré, Nicolas Le Thomas

We present a far-ﬁeld optical technique allowing measurements of the dispersion relation of electromagnetic ﬁelds propagating under the light cone in photonic nanostructures. It relies on the use of a one-dimensional grating to probe the evanescent tail of ...

2007

Exploring light propagating in photonic crystals with Fourier optics

Romuald Houdré, Nicolas Le Thomas

Photonic crystals (PhCs) act on light in two different ways: confinement and modification of propagation. Both phenomena rely on the complex interplay between multiply scattered waves that can form what is known as a Bloch mode. Here, we present a techniqu ...

Optical Society of America2007

On the kinetic stability of magnetic structures in electron drift turbulence

Martin Jucker

The generation of large-scale magnetic fields in magnetic electron drift mode turbulence is investigated. The mechanism of magnetic Reynolds stress is elucidated with the help of kinetic theory, and a sufficient criterion in the form of Nyquist's criterion ...

American Institute of Physics2007

Vibrational coherences of the protonated Schiff base of all-trans-retinal in solution

Majed Chergui, Goran Zgrablic, Stefan Haacke

Modulations in the time gated ultrafast fluorescence of the protonated Schiff base of retinal in various solvents are reported, which reflect the creation and evolution of vibrational wave packets due to the torsional mode of retinal of frequency .apprx.12 ...

2007

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