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DOE OSTI · 2565048

Vector-based feedback of continuous wave radiofrequency compression cavity for ultrafast electron diffraction

Sutter, Thomas M.·Lee, Joshua S. H.·Kulkarni, Atharva V.·Musumeci, Pietro·Kogar, Anshul
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Abstract

The temporal resolution of ultrafast electron diffraction at weakly relativistic beam energies (⁠≲100 keV) suffers from space-charge induced electron pulse broadening. We describe the implementation of a radio frequency (RF) cavity operating in the continuous wave regime to compress high repetition rate electron bunches from a 40.4 kV DC photoinjector for ultrafast electron diffraction applications. Active stabilization of the RF amplitude and phase through a feedback loop based on the demodulated in-phase and quadrature components of the RF signal is demonstrated. This scheme yields 144 ± 19 fs RMS temporal resolution in pump–probe studies.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYCondensed matter physicsDemodulatorsPulse compressionPump probe experimentsRadiofrequency cavitiesUltrafast electron diffraction

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Sutter, Thomas M., Lee, Joshua S. H., Kulkarni, Atharva V., Musumeci, Pietro, Kogar, Anshul. 2024-03-25. Vector-based feedback of continuous wave radiofrequency compression cavity for ultrafast electron diffraction. https://doi.org/10.1063/4.0000231

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