Single-shot measurement of the spectral envelope of broad-bandwidth terahertz pulses from femtosecond electron bunches.
We present a new approach (demonstrated experimentally and through modeling) to characterize the spectral envelope of a terahertz (THz) pulse in a single shot. The coherent THz pulse is produced by a femtosecond electron bunch and contains information on the bunch duration. The technique, involving a single low-power laser probe pulse, is an extension of the conventional spectral encoding method (limited in time resolution to hundreds of femtoseconds) into a regime only limited in resolution by the laser pulse length (tens of femtoseconds). While only the bunch duration is retrieved (and not the exact charge profile), such a measurement provides a useful and critical parameter for optimization of the electron accelerator.
van Tilborg
J
J
Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720, USA. JvanTilborg@lbl.gov
Tóth
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Matlis
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Plateau
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Leemans
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