Heavy crystal scintillators are used widely in HEP experiments for precision
measurements of photons and electrons. Future HEP experiments, however, require
crystal scintillators of more bright, more fast, more radiation hard and less
cost. This paper discusses several R&D directions for the next generation of
crystal detectors for future HEP experiments.Comment: 5 pages, 2 tables, white paper for the 2013 DPF Snowmass Summer Stud