Optical Improvements of Plastic Scintillators by Nanophotonics

Abstract

In this chapter, we discuss the optical improvements of plastic scintillators by nanophotonics, which are mainly focused on the methods to enhance the light extraction efficiency rather than increasing the internal quantum efficiency of plastic scintillators. This is a typical application of the knowledge of nanophotonics, such as photonic crystals and plasmonic lattice resonance on plastic scintillators. Total internal reflection strongly limits light extraction. An important breakthrough can be achieved thanks to nanostructures with wavelength scales on the surface of plastic scintillators, giving rise to directional and wavelength-dependent emission enhancement and thus enhancing the performance of scintillation-based detectors. Underlying physical mechanisms are discussed in detail. Suitable patterning techniques for the surfaces of plastic scintillators, including nanoimprint lithography, self-assembly lithography and X-ray interference lithography are introduced. As an application, we present a typical example of the enhanced ability of neutron detection by photonic crystals on plastic scintillators. It should be emphasized that the application of nanophotonics principles on light output of plastic scintillators could be combined with traditional coupling methods with the aim at the optimization of detection performance.