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nanotimes News in Brief

11-04 :: April/May 2011

Electrons // Controlled near-field Enhanced Electron Acceleration from Dielectric Nanospheres

Optics, Germany, to control and monitor strongly accelerated electrons from nanospheres with extre- mely short and intense laser pulses.

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When intense laser light interacts with electrons in nanoparticles that consist of many million individual atoms, these electrons can be released and strongly accelerated. Such an effect in nano-spheres of silica was recently observed by an international team of researchers in the Laboratory for Attosecond Physics (LAP) at the Max Planck Institute of Quantum Optics. The researchers report how strong electrical fields (near-fields) build up in the vicinity of the nanoparti- cles and release electrons. Driven by the near-fields and collective interactions of the charges resulting from ionization by the laser light, the released elec- trons are accelerated, such that they can by far exceed the limits in acceleration that were observed so far for single atoms. The exact movement of the electrons can be precisely controlled via the electric field of the laser light. The new insights into this light- controlled process can help to generate energetic extreme ultraviolet (XUV) radiation. The experiments and their theoretical modeling, which are described by the scientists in the journal “Nature Physics,” open up new perspectives for the development of ul- trafast, light-controlled nano-electronics, which could

n international team of researchers succeeded at the Max Planck Institute of Quantum

potentially operate up to one million times faster than current electronics.

For the first time, the researchers could observe and record the direct elastic recollision pheno- menon from a nanosystem in detail. The scientists used polarized light for their experiments. With polarized light, the light waves are oscillating only along one axis and not, as with normal light, in all directions.

Sergey Zherebtsov, Thomas Fennel, Jürgen Plenge, Egill Antonsson, Irina Znakovskaya, Adrian Wirth, Oliver Herr- werth, Frederik Süßmann, Christian Peltz, Izhar Ahmad, Sergei A. Trushin, Vladimir Pervak, Stefan Karsch1, Marc J.J. Vrakking, Burkhard Langer, Christina Graf, Mark I. Stockman, Ferenc Krausz, Eckart Rühl, Matthias F. Kling: Controlled near-field enhanced electron acceleration from dielectric nanospheres with intense few-cycle laser fields, In: Nature Physics AOP, April 24, 2011, DOI: 10.1038/ NPHYS1983: http://dx.doi.org/10.1038/NPHYS1983

Prof. Dr. Matthias Kling, Garching: http://www.attoworld.de/kling-group/ Prof. Dr. Eckart Rühl, Berlin: http://userpage.chemie.fu-berlin.de/~ruehl/ Prof. Dr. Thomas Fennel, Rostock: http://web.physik.uni-rostock.de/clustertheorie/