Abstract
To meet detector performance benchmarks set for medical imaging, high energy physics and national security applications, scintillator materials with picosecond-scale timing and high light yield have been created. These epitaxially grown GaAs crystals contain InAs quantum dots (QDs) forming a semiconductor heterostructure which emits light at wavelengths where GaAs is transparent. Total internal reflection (TIR) provides a cladding effect and monolithic photodetector (PD) integration enables efficient light collection. Previously, we reported on devices with complex, high variance responses to monoenergetic sources. The origin of these responses is now elucidated and utilized to achieve material-related energy resolution values of 2.4% with alpha particles. These findings place energy resolution alongside luminescence timescale, photon yield, and radiation hardness as favorable properties of these engineered materials.