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High-purity free-electron momentum states prepared by three-dimensional optical phase modulation

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 نشر من قبل Armin Feist
 تاريخ النشر 2020
  مجال البحث فيزياء
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We demonstrate the quantized transfer of photon energy and transverse momentum to a high-coherence electron beam. In an ultrafast transmission electron microscope, a three-dimensional phase modulation of the electron wavefunction is induced by transmitting the beam through a laser-illuminated thin graphite sheet. This all-optical free-electron phase space control results in high-purity superpositions of linear momentum states, providing an elementary component for optically programmable electron phase plates and beam splitters.

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