Eric Black is a Lecturer of Physics at the California Institute of Technology, where he splits his time between teaching the Senior Physics Lab and researching technologies for the next generation of interferometric gravitational-wave detectors. He received his Ph.D. from the University of Colorado at Boulder in 1997 for work in electron transport in mesoscopic systems at low temperature.
Dr. Eric D. Black, California Institute of Technology, Department of Physics, MC 264-33 Pasadena, CA 91125. Email: blacke@its.caltech.edu. Telephone: 626-395-3858.
Saturated-absorption, or “Doppler-free,” spectroscopy is a widespread and useful tool for modern atomic physics. As the name suggests, it allows the effective removal of the Doppler broadening in absorption lines of an atomic vapor. The basic idea is to use counterpropagating “pump” and “probe” beams of the same frequency (generated by the same laser) to select for and probe only those atoms whose velocity component parallel to the beams is zero, i.e. those atoms moving at right angles to the laser beams. This allows us to do spectroscopy limited only by the natural linewidth of the atomic transitions, revealing features of the absorption lines that would otherwise be unobservable in a gas at room temperature.
In this lab, participants will use a Teachspin laser-diode apparatus and a cell of Rubidium vapor to learn how to do Doppler-free spectroscopy in hydrogen-like atoms. After learning the basics of diode lasers and saturated-absorption spectroscopy, they will calibrate the system using an asymmetric Michelson interferometer and measure the hyperfine splitting of the P3/2 levels of both 85Rb and 87Rb.
Participants need only bring a lab notebook and a pen. All hardware and reading material will be provided.