Simulated nuclear radiation responses derived from nanocrystalline semiconductor assemblies

Nanocrystalline semiconductor detectors comprised of either cadmium or lead chalcogenide nanoparticles have resulted in excellent energy resolution. For instance, a blended assembly of 4 nm PbSe star-shaped particles, has yielded an energy resolution of 0.42 % (1.5 keV) at 356 keV, compared with a resolution of 0.96 % (3.4 keV) for CZT and 0.39 % (1.4 keV) for HPGe. The spectra are characterized however, by x-ray escape features due to the high probability of photoelectric absorption in the lead-based assembly, as well as the high x-ray energies associated with high Z materials. In this paper, we simulate the spectral response of a composite detector composed of PbSe and para-MEH-PPV in order to aid in the identification of the various features.