Bright and ultra-fast scintillation from a semiconductor?

Area of Science:

• Materials Science
• Nuclear Instrumentation
• Solid-State Physics

Background:

• Semiconductor scintillators exhibit superior luminosity and decay times compared to other scintillator types.
• Many semiconductors incorporate heavy elements (e.g., Tl, Hg, Pb, Bi) and offer high ion pair yield proportional to deposited energy.

Purpose of the Study:

• To review scintillation properties of semiconductors activated by native defects, impurities, donors, and acceptors.
• To highlight semiconductors with exceptionally high luminosity (e.g., ZnO:Zn, ZnS:Ag,Cl, CdS:Ag,Cl) and ultra-fast decay times (e.g., ZnO:Ga; CdS:In).
• To discuss mechanisms and potential for achieving specific performance targets in scintillation detectors.

Main Methods:

• Review of existing literature on semiconductor scintillator properties.
• Analysis of scintillation mechanisms related to material composition and activation.
• Exploration of theoretical possibilities for detector performance enhancement.

Main Results:

• Identification of semiconductor materials with high luminosity and ultra-fast decay characteristics.
• Discussion of underlying physical mechanisms governing scintillation in these materials.
• Assessment of potential for achieving high photon yields, energy resolution, and fast timing.

Conclusions:

• Semiconductor scintillators are promising for high-performance radiation detection.
• Further research can optimize materials for applications like positron emission tomography.
• Cryogenic temperatures may enable simultaneous high luminosity and ultra-fast decay.