Jan A. Northby


Ph. D.  University of Minnesota 1966
SB.  Massachusetts Institute of Technology 1959     

Research Interests:

  • Experimental quantum fluids
  • Low-temperature physics
  • Cluster ion beams

Prof. Jan Northby works in experimental low-temperature physics, studying beams of superfluid helium nanodroplets. The primary motivation is to learn about the effect of finite size on superfluidity. In order to study such a weakly interacting system it is necessary to create or attach a probe particle of some sort. His research program has centered on those particles created in clusters by electron bombardment.

Most recently, the group has been studying the spectroscopy of metastable helium molecules attached to the surface of helium nanodroplets. The study exploits a new kind of laser spectroscopy in which absorption of a photon leads to the detachment of a metastable particle from the surface. In addition to studying the spectral modifications induced by the particle-surface interaction, the high detectability of such particles permits measurements of their recoil momentum. This in turn provides additional insight into their dynamical interaction with the nanodroplet.

Other experimental projects underway in Prof. Northby's laboratory include the development of beam sources of metastable helium molecules, and the development of a laser based sediment velocimeter that can be used to study sediment concentration and motion in natural waters.

List of Recent Publications

Helium Cluster Beam Apparatus

sketch of helium cluster beam apparatus
Contact Information:
Email:  jnorthby@uri.edu
Phone:  401-874-2042 (office) 401-874-2074 (lab)
Office:  Room 314, East Hall
 |  Department of Physics  |  University of Rhode Island  |