Stimulated Raman Adiabatic Passage for Improved Performance of a Cold Atom Electron and Ion Source

• Main Authors: Sparkes, B. M, Murphy, D, Taylor, R. J, Speirs, R. W, McCulloch, A. J, Scholten, R. E
• Format: Journal Article
• Language: English
• Published: 13-07-2016
• Subjects: Physics - Atomic Physics; Physics - Quantum Physics
• DOI: 10.48550/arxiv.1602.07791

Phys. Rev. A 94, 023404 (2016) We implement high-efficiency coherent excitation to a Rydberg state using
stimulated Raman adiabatic passage in a cold atom electron and ion source. We
achieve an efficiency of 60% averaged over the laser excitation volume with a
peak efficiency of 82%, a 1.6 times improvement relative to incoherent
pulsed-laser excitation. Using pulsed electric field ionization of the Rydberg
atoms we create electron bunches with durations of 250 ps. High-efficiency
excitation will increase source brightness, crucial for ultrafast electron
diffraction experiments, and coherent excitation to high-lying Rydberg states
could allow for the reduction of internal bunch heating and the creation of a
high-speed single ion source.