Virtual Journal of Laser

Author(s): O. Lundh, C. Rechatin, J. Lim, V. Malka, and J. Faure

Spectral measurements of visible coherent transition radiation produced by a laser-plasma-accelerated electron beam are reported. The significant periodic modulations that are observed in the spectrum result from the interference of transition radiation produced by multiple bunches of electrons. A F...

[Phys. Rev. Lett. 110, 065005] Published Fri Feb 08, 2013

Author(s): V. M. Ovchinnikov, D. W. Schumacher, M. McMahon, E. A. Chowdhury, C. D. Chen, A. Morace, and R. R. Freeman

We report on a numerical study of the effects of preplasma scale length and laser intensity on the hot-electron (≥1  MeV) divergence angle using full-scale 2D3V (two dimensional in space, three dimensional in velocity) simulations including a self-consistent laser-plasma interaction and photoionizat...

[Phys. Rev. Lett. 110, 065007] Published Fri Feb 08, 2013

Author(s): S. Martin, J. Bernard, R. Brédy, B. Concina, C. Joblin, M. Ji, C. Ortega, and L. Chen

Fast radiative cooling of anthracene was observed in a compact electrostatic storage ring by probing the evolution of the internal energy distribution of a stored (C₁₄H₁₀)⁺ molecular ensemble via laser excitation. We have measured the mean radiative decay rate to be about 120 to 250  s^-1 for interna...

[Phys. Rev. Lett. 110, 063003] Published Thu Feb 07, 2013

Author(s): M. Cerchez, A. L. Giesecke, C. Peth, M. Toncian, B. Albertazzi, J. Fuchs, O. Willi, and T. Toncian

The first experimental evidence of the higher-order harmonic radiation generated by periodically modulated targets (gratings) irradiated by relativistic, ultrashort (<30  fs), high intensity [Iλ²=10²⁰  (W/cm²) μm²] laser pulse is presented. The interference effects on the grating surface lead to ...

[Phys. Rev. Lett. 110, 065003] Published Thu Feb 07, 2013

Author(s): Chao Chang, Chuanxiang Tang, and Juhao Wu

A novel approach to generating coherent x rays with 10⁹–10¹⁰ photons and femtoseconds duration per laser pulse is proposed. This high intensity x-ray source is realized first by the pulse front tilt of a lateral fed laser to extend the electron-laser synchronic interaction time by several orders, wh...

[Phys. Rev. Lett. 110, 064802] Published Tue Feb 05, 2013

Author(s): T. Ma, T. Döppner, R. W. Falcone, L. Fletcher, C. Fortmann, D. O. Gericke, O. L. Landen, H. J. Lee, A. Pak, J. Vorberger, K. Wünsch, and S. H. Glenzer

The strong ion-ion correlation peak characteristic of warm dense matter (WDM) is observed for the first time using simultaneous angularly, temporally, and spectrally resolved x-ray scattering measurements in laser-driven shock-compressed aluminum. Laser-produced molybdenum x-ray line emission at an ...

[Phys. Rev. Lett. 110, 065001] Published Tue Feb 05, 2013

Author(s): Giovanni De Ninno, Benoît Mahieu, Enrico Allaria, Luca Giannessi, and Simone Spampinati

We demonstrate the possibility of running a single-pass free electron laser (FEL) in a dynamical regime, which can be exploited to perform two-color pump-probe experiments in the vacuum ultraviolet or x-ray domain, using the free-electron laser emission both as a pump and as a probe. The studied reg...

[Phys. Rev. Lett. 110, 064801] Published Mon Feb 04, 2013

Author(s): J. A. Pérez-Hernández, M. F. Ciappina, M. Lewenstein, L. Roso, and A. Zaïr

We present numerical simulations of high-order harmonic generation in helium using a temporally synthesized and spatially nonhomogeneous strong laser field. The combination of temporal and spatial laser field synthesis results in a dramatic cutoff extension far beyond the usual semiclassical limit. ...

[Phys. Rev. Lett. 110, 053001] Published Mon Jan 28, 2013

Author(s): F. Tournus, K. Sato, T. Epicier, T. J. Konno, and V. Dupuis

The atomic structure of CoPt and FePt nanoparticles (with a diameter between 2 and 5 nm) has been studied by transmission electron microscopy. The particles have been produced by a laser vaporization cluster source and annealed under vacuum in order to promote chemical ordering. For both alloys, we ...

[Phys. Rev. Lett. 110, 055501] Published Mon Jan 28, 2013

Author(s): Vassilios Yannopapas and Nikolay V. Vitanov

We demonstrate theoretically that it is possible to exercise coherent control of the temperature in nanostructures by laser fields. In particular we show that by use of nanosecond laser pulses it is possible to induce a temperature distribution on a collection of nanoparticles which can last for up ...

[Phys. Rev. Lett. 110, 044302] Published Fri Jan 25, 2013