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

• Main Authors: Jere Harrison, Yongha Hwang, Omeed Paydar, Jimmy Wu, Evan Threlkeld, James Rosenzweig, Pietro Musumeci, Rob Candler
• Format: Article
• Language: English
• Published: American Physical Society 2015-02-01
• Series: Physical Review Special Topics. Accelerators and Beams
• Online Access: http://doi.org/10.1103/PhysRevSTAB.18.023501

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.