Electron Spin Resonance

University of Chicago, July 13-15, 2018
(One set-up available)

We will study how a classical “particle” having magnetic dipole moment and angular momentum responds to an external magnetic field. We will relate these findings to quantum mechanical properties of electrons. We will study energy and angular momentum transfer from rotating fields to the particle. Use of a classical analog helps the student develop a model to better understand the quantum mechanical electron spin resonance.

This experiment will be performed on one day of the three-day immersion. In the classical system measurements will be made of the magnetic dipole moment and angular momentum of a ball riding on an air bearing. The relation among magnetic moment, angular momentum, magnetic field and precession frequency will be determined. This relation will be used to understand similar relations for electron spin resonance.

Skills that will be acquired performing the experiments include spin frequency measurement using a strobe light; use of a digital scope for careful measurements of resonance conditions; and building a classical theoretical model and applying it to a quantum system.


Figure 1: TeachSpin Magnetic Torque apparatus, Daedalon Electron Spin apparatus, digital oscilloscope.

A lab notebook should be brought. A laptop would be useful, but not mandatory. There are no safety considerations.

A cost estimate for the equipment required to implement the experiment is $6,000.

Follow this link to watch a video overview of the ESR Immersion.

Host and Mentor:

Van Bistrow received his B.A. with an emphasis on Philosophy of Science in 1966 from the University of Wisconsin, Madison. He received his Master of Arts in Teaching Physics in 1973 and his M.S. degree in Physics in 1974, both from the University of Chicago. In 1974 he began working full-time in the instructional labs at UChicago, and in 1997 he was promoted to Director of Instructional Labs. In this capacity he teaches, develops lab exercises, writes lab manuals, trains TAs and is a member of the Physics Department's Teaching Activities Committee. He has been an active member of the American Association of Physics Teachers. In that setting he has led workshops on Advanced and Intermediate Instructional Labs, served on and was spokesman for the AAPT Advanced Labs Task Force, charged with identifying ways AAPT could help Advanced Lab developers. He helped with the design of AAPT's Advanced Labs website, and was co-organizer and presenter at the Conference on Instructional Labs "Beyond the First Year" at the University of Michigan, Ann Arbor. He is a member of the Advanced Labs Physics Association, ALPhA, co-presenting an ALPhA Immersion on Single-Photon Interference at the University of Chicago. Van was presented with the 2016 Jonathan F. Reichert and Barbara Wolff-Reichert Award for Excellence in Advanced Laboratory Instruction by the American Physical Society.

Van Bistrow, Director of Instructional Laboratories, University of Chicago, Department of Physics, 5720 S. Ellis Ave., Chicago, IL 60637.  Email Address: vanb@uchicago.edu. Phone: 773-702-7013.

Please note that the Jonathan F. Reichert Foundation has established a grant program to help purchase apparatus used in Laboratory Immersions. Limitations and exclusions apply, but generally speaking the foundation may support up to 40% of the cost of the required equipment.