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Brenton Knuffman

Brenton Knuffman is a Visiting Researcher in the Alternative Computing Group and a co-founder of zeroK Nanotech Corporation. He received a B.S. in Physics from Loyola University Chicago and a Ph.D. in Applied Physics from the University of Michigan, where his dissertation focused on studies of cold Rydberg atoms and ultracold plasmas. He then worked as a CNST/UMD Postdoctoral Researcher in the Electron Physics Group developing a new type of ion microscope that uses photo-ionized, laser-cooled atoms as its source. He is currently working with Jabez McClelland under a cooperative research and development agreement (CRADA) constructing a prototype of a low-temperature ion source, which utilizes the extremely cold temperatures attainable with laser cooling to produce a highly collimated, bright ion beam.

Selected Publications

  • Cold atomic beam ion source for focused ion beam applications, B. Knuffman, A. V. Steele, and J. J. McClelland, Journal of Applied Physics 114, 044303 (2013).
    NIST Publication Database Journal Web Site
  • Nanoscale focused ion beam from laser-cooled lithium atoms, B. Knuffman, A. V. Steele, J. Orloff, and J. J. McClelland, New Journal of Physics 13, 103035 (2011).
    NIST Publication Database        Journal Web Site
  • Inter-ion coulomb interactions in a magneto-optical trap ion source, A. V. Steele, B. Knuffman, and J. J. McClelland, Journal of Applied Physics 109, 104308 (2011).
    NIST Publication Database        Journal Web Site
  • State-dependent energy shifts of Rydberg atoms in a ponderomotive optical lattice, K. C. Younge, B. Knuffman, S. E. Anderson, and G. Raithel. Physical Review Letters 104, 173001 (2010).
  • Multipole Transitions of Rydberg Atoms in Modulated Ponderomotive Potentials, B. Knuffman and G. Raithel, Physical Review A 75, 053401 (2007).


Bright focused ion beam sources based on laser-cooled atoms

Jabez J. McClelland, Adam V. Steele, Brenton J. Knuffman, Kevin A. Twedt, Andrew D. Schwarzkopf, Truman M. Wilson
Nanoscale focused ion beams (FIBs) represent one of the most useful tools in nanotechnology, enabling nanofabrication via milling and gas-assisted deposition

Nanoscale Focused Ion Beam from Laser-cooled Lithium Atoms

Brenton J. Knuffman, Adam V. Steele, Jon Orloff, Jabez J. McClelland
To advance the capabilities of focused ion beam (FIB) technology, we have created a low-energy FIB from photoionized lithium atoms collected in a magneto
Created July 30, 2019, Updated October 9, 2019