Over the last three decades Ren-Yuan Zhu and his colleagues have been involved in the successful development
of scintillating crystals for precision crystal electromagnetic calorimeter in high energy physics,
such as the L3 BGO, BaBar CsI(Tl) and CMS PWO. Several Advanced Detector Research awards and Collider
Detector Research and Development awards were received from DOE Science Office for the development of PWO,
LSO/LYSO and other cost-effective crystals for future HEP experiments at the energy and intensity frontiers.
In 2009, Ren-Yuan Zhu established a program for crystal development in the Caltech HEP. The main goal of
this program is to develop novel detector concept based upon crystal scintillators for future HEP experiments,
such as LSO/LYSO crystal based total absorption and sampling calorimeters, very fast crystal calorimeters as well as a cost-effective crystal scintillator based homogeneous hadronic calorimeter detector concept. Recent emphasis of this advanced detector research effort is also devoted to the development of ultra-fast crystal scintillators with good radiation hardness and low cost. This work was supported by the DOE Office of Science (Office of Basic Energy Sciences).