Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Attosecond flashes from solid-density relativistic plasmas

16.12.2008
MPQ scientists have demonstrated the generation of attosecond flashes with unprecedented intensity

Recent innovations in laser technology have provided radiation sources for attosecond (10 to the power of -18 sec) light flashes that can freeze the ultrafast motion of electrons inside atoms and molecules.

The range of possible applications is however limited by the low flux of the current attosecond sources. In a proof of principle experiment a team of MPQ scientists (Attosecond and High-Field Physics Division, Prof. Ferenc Krausz) has now demonstrated a novel way of generating attosecond light flashes with unprecedented intensity. The article by Y. Nomura et al., (Nature Physics, Advance Online Publication December 14, 2008, DOI 10.1038) confirms that relativistically driven overdense plasmas are able to convert infrared laser light into harmonic XUV radiation with high efficiency.

Furthermore it demonstrates the feasibility of confining unprecedented amounts of light energy to within less than one femtosecond. The long term goal - reaching sub-atomic resolution simultaneously in space and time - will have far-reaching impact, from physics and chemistry through biology and medicine to future information technologies.

State of the art technique for producing ultrashort coherent light pulses in the XUV spectral range is the method of generating "harmonics" by converting laser light travelling through a gas target to radiation whose frequency is an integer times the frequency of the fundamental oscillation. By contrast the scientists focus short laser pulses from the Titanium-Sapphire-Laser ATLAS (IR, 800 nm) onto a solid target creating an overdense plasma on its surface in which the electrons oscillate in the strong laser field with velocities close to the speed of light. Here two mechanisms give rise to harmonic generation. On the one hand the electrons reflect the incoming laser light causing (depending on their direction) a Doppler shift towards higher frequencies. On the other hand - and this process is the dominant one in this work - the electrons that are injected into the surface excite plasma waves in their wake. Under certain conditions these are converted to electromagnetic radiation at higher harmonics of the driver frequency. A spectral filter suppresses residual IR-light and selects a range of harmonics.

"There is no way to measure the time structure of the sequence of out coming attosecond flashes directly", says Dr. George Tsakiris, leader of the project. "We therefore have to resume to a trick: we let two replica of the attosecond pulse train interact with a Helium gas jet. By varying the time delay between them and recording the corresponding number of resulting Helium ions we can deduce the temporal structure of the XUV radiation." "We have demonstrated for the first time that the harmonics from solid targets are indeed emitted as a train of attosecond pulses", adds Rainer Hörlein, PhD student at the experiment.

More generally spoken the physicists have demonstrated the first alternative method to the generation of harmonics from noble gases for the production of attosecond pulses. In addition the pulses are orders of magnitude more intense than those generated with conventional methods. Unlike gas-harmonics the new method is expected to be highly scalable and to exhibit no limitation on the usable laser intensity: the higher the laser intensity the shorter and more energetic the attosecond pulses should be. Much more intense attosecond pulses will significantly increase the scope of possible experiments with attosecond resolution and will make pump-probe experiments with attosecond pulses feasible. [O.M.]

Original publication:
Y. Nomura, R. Hörlein, P. Tzallas, B. Dromey, S. Rykovanov, Zs. Major, J. Osterhoff, S. Karsch, L. Veisz, M. Zepf, D. Charalambidis, F. Krausz, and G. D. Tsakiris
"Attosecond phase locking of harmonics emitted from laser-produced plasmas"
Nature Physics, Advance Online Publication December 14th, 2008, DOI 10.1038
Contact:
Dr. George Tsakiris
Max Planck Institute of Quantum Optics
Hans Kopfermann Straße 1
85748 Garching
Phone: +49(0)89 32905 240
Fax: +49(0)89 32905 200
E-mail: george.tsakiris@mpq.mpg.de
Dr. Olivia Meyer-Streng
Press & Public Relations
Max Planck Institute of Quantum Optics
Phone: +49(0)89 32905 213
Fax: +49(0)89 32905 200
E-mail: olivia.meyer-streng@mpq.mpg.de

Dr. Olivia Meyer-Streng | Max-Planck-Gesellschaft
Further information:
http://www.mpq.mpg.de

More articles from Physics and Astronomy:

nachricht Quantum optical sensor for the first time tested in space – with a laser system from Berlin
23.01.2017 | Ferdinand-Braun-Institut Leibniz-Institut für Höchstfrequenztechnik

nachricht SF State astronomer searches for signs of life on Wolf 1061 exoplanet
20.01.2017 | San Francisco State University

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Quantum optical sensor for the first time tested in space – with a laser system from Berlin

For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.

According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

New technology for mass-production of complex molded composite components

23.01.2017 | Process Engineering

Quantum optical sensor for the first time tested in space – with a laser system from Berlin

23.01.2017 | Physics and Astronomy

The interactome of infected neural cells reveals new therapeutic targets for Zika

23.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>