Radiation-photon converter based on GaN single crystal coupled with multi-quantum-well luminescence structure

Converting radiation into optical signals is a fundamental method for nuclear radiation detection. However, traditional scintillators encounter a trade-off between efficiency and response speed. This research proposes a radiation-photon converter constructed from multi-quantum-well (MQW) structures integrated into radiation-sensitive materials, providing a unique solution to this challenge. The prototype was fabricated using a homogeneous epitaxial layer of GaN on a semi-insulating substrate. The radiation-photon conversion process was facilitated by directing charge carriers generated from radiation energy deposited in the semi-insulating substrate to the MQW layer via an external electric field. The converter exhibited a sensitive and rapid response to x-ray irradiation, enabling modulation of the excited photon wavelength through the MQW layers. Luminescence spectrum tests demonstrated that the net luminescence intensity increased with rising device voltage. Imaging experiments revealed that the grayscale values of device photographs, under the combined influence of electric fields and x rays, correlated with the trend in net current variation. These findings confirmed the effective conversion of radiation into optical signals through the modulation mechanism of the electric field, highlighting significant implications for the development of advanced radiation detection methodologies.