References and Links
Overview
Dan Leopold (also at Washington University) is currently developing novel high quantum efficiency photocathodes for use in photomultiplier tubes and image intensifiers. This NASA supported research and development makes use of a molecular beam epitaxy lab operated here at Washington University (see image at left). The proposed tailored heteroepitaxical semiconductor cathodes should achieve a peak sensitivity in the UV/blue range in excess of 60%.
Motivation
The initial motivation for developing these photocathodes was to aid in several new high-energy astrophysics projects. These experiments use detectors that make use of scintillation light produced in optical fibers or Cherenkov light produced in the atmosphere or in solid converters. Both Cherenkov and scintillation light have typical emission spectra which peak in the UV band. More efficient detectors in this band will allow signals which would normally be washed out by background noise to be resolved in these experiments. (see the OJI project page and Dark Matter annihilation).
hbar.wustl.edu>