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arXiv · 2311.16400

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

Thomas Sutter·Joshua Lee·Atharva Kulkarni·Pietro Musumeci·Anshul Kogar
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Abstract

The temporal resolution of ultrafast electron diffraction (UED) at weakly relativistic beam energies ($\lesssim$ 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$\pm$19 fs RMS temporal resolution in pump-probe studies.

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Thomas Sutter, Joshua Lee, Atharva Kulkarni, Pietro Musumeci, Anshul Kogar. 2023-11-28. Vector-based feedback of continuous wave radiofrequency compression cavity for ultrafast electron diffraction. https://doi.org/10.1063/4.0000231

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