Letter abstract


Nature Physics 4, 390 - 393 (2008)
Published online: 30 March 2008 | doi:10.1038/nphys916

Subject Categories: Optical physics | Particle physics | Techniques and instrumentation

Tunable narrowband terahertz emission from mastered laser–electron beam interaction

S. Bielawski1,2, C. Evain2, T. Hara1,6, M. Hosaka3, M. Katoh1,4, S. Kimura1,4, A. Mochihashi1,4, M. Shimada1, C. Szwaj2, T. Takahashi5 & Y. Takashima3

Top

In the quest for sources of optical radiation in the terahertz domain, promising candidates are nonlinear optical processes occurring when an intense laser beam interacts with a material medium1, 2, 3, 4, 5. Besides conventional media (such as crystals), relativistic electrons also show striking nonlinear collective behaviours, which can lead to powerful laser-induced coherent emission6, 7, revealing huge potentials of these devices as terahertz sources8. However, up to now only broadband emissions were reported, and experimental control of their radiation properties, such as their spectra9, 10, remained an important challenge. Here, we demonstrate the possibility of mastering the coherent emission experimentally by producing tunable narrowband terahertz radiation. The interaction is made to occur between an electron beam and laser pulses possessing a longitudinal quasi-sinusoidal modulation, and the narrowband emission occurs in a region of quasi-uniform magnetic field. The process therefore strongly differs from classical synchrotron radiation experiments, where narrowband emission occurs inside a periodic magnetic field.

Top
  1. UVSOR Facility, Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki 444-8585, Japan
  2. Laboratoire PhLAM, UMR CNRS 8523, CERLA, FR CNRS 2416, Université des Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq Cedex, France
  3. Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
  4. School of Physical Sciences, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8585, Japan
  5. Research Reactor Institute, Kyoto University, Kumatori-cho, Osaka 590-0494, Japan
  6. Permanent address: RIKEN SPring-8 Centre, Harima Institute, Sayo-cho, Hyogo 679-5148, Japan

Correspondence to: S. Bielawski1,2 e-mail: serge.bielawski@univ-lille1.fr



MORE ARTICLES LIKE THIS

These links to content published by NPG are automatically generated.

NEWS AND VIEWS

Radiation sources Electrons and lasers sing THz tune

Nature Physics News and Views (01 May 2008)


Extra navigation

Subscribe to Nature Physics

Subscribe

naturejobs

ADVERTISEMENT