Physical Review Special Topics. Accelerators and Beams (Feb 2015)

High-gradient microelectromechanical system quadrupole electromagnets for particle beam focusing and steering

  • Jere Harrison,
  • Yongha Hwang,
  • Omeed Paydar,
  • Jimmy Wu,
  • Evan Threlkeld,
  • James Rosenzweig,
  • Pietro Musumeci,
  • Rob Candler

DOI
https://doi.org/10.1103/PhysRevSTAB.18.023501
Journal volume & issue
Vol. 18, no. 2
p. 023501

Abstract

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Recent advancements in microelectromechanical system (MEMS) fabrication techniques have enabled the batch-fabrication of quadrupole MEMS electromagnets producing 100 mT-scale field across sub-mm gaps with the potential for transformational advances in the field of compact high performance charged particle focusing and steering optics. The footprint of these in-vacuum focusing and steering optics can be as small as 3 mm×3 mm×0.5 mm. The low electromagnet impedance (58 mΩ, 32 nH per pole) facilitates power-efficient operation and continuous or low duty cycle operation, and the individually controlled electromagnets allow combined dipole-quadrupole fields. Here we report on an experiment where these miniature devices have been used to focus and steer a 34 keV electron beam from a DC photogun, demonstrating the first application of magnetic MEMS to particle beam focusing.