Position Type
- Present

I have been at Denison since 1996, following teaching experience at Saint Mary’s College of California and a research postdoc at SRI International. I enjoy teaching a broad range of courses including introductory physics, introductory astronomy, modern physics, electromagnetic theory, electronics and advanced lab. In addition, I have developed and taught several courses specifically for non-science majors, including “”Renewable Energy and Sustainability” (FYS 102), “Energy and the Environment” (Physics 100) and “Coming of Age in the Milky Way: Aristotle to Galileo to Einstein” (Honors 135 and FYS 102). I am an active member of the American Physical Society, the American Association of Physics Teachers, the Council on Undergraduate Research, and Project Kaleidoscope — F21.

B.S., University of Dallas; M.A., Ph.D., Rice University


Research Overview
Experimental research on negative ion spectroscopy, atomic and molecular structure, and dynamics. Studies how electrons interact at the quantum level using lasers on-campus and high-energy synchrotron light at Lawrence Berkeley National Lab.
Research Details

My research interests include laser spectroscopy, negative ions, and atomic and molecular collisions. The overall goal of our research program is to understand better the fundamental physics of electron binding particularly regarding the role of electron correlations, that is, how electrons "talk" to each other within an atom. Together with Prof. Dan Gibson (also of Denison's Physics Department) and many student collaborators, we have developed an on-campus ion beam mass spectrometer to investigate properties of negative ions using lasers. We do complementary experiments using the synchrotron Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory in California. Our projects have included: investigations of the effects of static electric fields on laser photodetachment from negative ions (which leads to the formation of single electron interferometers); precision measurements of atomic electron affinities using tunable photodetachment spectroscopy; and investigations of inner-shell photodetachment at the ALS. This research is funded by grants from the National Science Foundation, the Research Corporation, and Denison University. Interested students are always welcome to join our research group!




  • Alban Kellerbauer, Giovanni Cerchiari, Elena Jordan, and C. W. Walter, “High-resolution Laser Spectroscopy on Bound–Bound Transitions in La–”, Physica Scripta 90, 054014 (2015).
  • C.W. Walter, N. D. Gibson, D. J. Matyas*, C. Crocker*, K.A. Dungan*, B.R. Matola*, and J. Rohlén, “Candidate for Laser Cooling of a Negative Ion: Observations of Bound-Bound Transitions in La–”, Physical Review Letters 113, 063001 (2014).
  • R.C. Bilodeau, N.D. Gibson, C.W. Walter, D.A. Esteves-Macaluso, S. Schippers, A. Müller, R.A. Phaneuf, A. Aguilar, M. Hoener, J.M. Rost, and N. Berrah, “Single-Photon Multiple-Detachment in Fullerene Negative Ions: Absolute Ionization Cross Sections and the Role of the Extra Electron”, Physical Review Letters 111, 043003 (2013).
  • A. O. Lindahl, J. Rohlén, H. Hultgren, I. Yu. Kiyan, D. J. Pegg, C. W. Walter, and D. Hanstorp, “Threshold Photodetachment in a Repulsive Potential”, Physical Review Letters 108, 033004 (2012).
  • C.W. Walter, N.D. Gibson, Y.-G. Li*, D. J. Matyas*, R.M. Alton*, S.E. Lou*, R.L. Field III*, D. Hanstorp, L. Pan, and D.R. Beck, “Experimental and Theoretical Study of Bound and Quasi-bound States of Ce”, Physical Review A 84, 032514 (2011).
  • C.W. Walter, N.D. Gibson, D. J. Carman*, Y.-G. Li*, and D. J. Matyas*, “Electron Affinity of Indium and the Fine Structure of In Measured using Infrared Photodetachment Threshold Spectroscopy”, Physical Review A 82, 032507 (2010).
  • C.W. Walter, N.D. Gibson, R.L. Field III*, A.P. Snedden*, J.Z. Shapiro*, C. M. Janczak*, D. Hanstorp, “Electron Affinity of Arsenic and the Fine Structure of As Measured using Infrared Photodetachment Threshold Spectroscopy”, Physical Review A 80, 014501 (2009).

* Denison student