The peculiar photoluminescence properties of radiation-induced electronic defects in lithium fluoride (LiF), known as color centers, are well known for applications in tunable lasers and photonic light-emitting microdevices operating at room temperature. In the last two decades they have been under exploitation in radiation imaging detectors and dosimeters based on the optical reading of the visible photoluminescence in LiF crystals and polycrystalline thin films. They were proposed for soft X-ray imaging at high spatial resolution and, more recently, their use has been successfully applied to advanced diagnostics of proton beams. After proton irradiation of LiF, the emission intensity of the radiation-induced point defects is proportional to the absorbed dose over several orders of magnitude, thus novel solid-state dosimeters with imaging capabilities can be envisaged, although dose values that are typical of clinical radiotherapy are still a challenge. In this brief review, the main experimental results and recent advances concerning radiophotoluminescence of color centers in optically transparent LiF crystals and polycrystalline thin films are presented and discussed in order to highlight the advantages, challenges and limits related to the feasibility of detectors for protontherapy applications.
Radiophotoluminescence of color centers in lithium fluoride for novel radiation detectors in proton-beam diagnostics and clinical dosimetry
Montereali R. M.;Nichelatti E.;Piccinini M.;Nigro V.;Vincenti M. A.
2021-01-01
Abstract
The peculiar photoluminescence properties of radiation-induced electronic defects in lithium fluoride (LiF), known as color centers, are well known for applications in tunable lasers and photonic light-emitting microdevices operating at room temperature. In the last two decades they have been under exploitation in radiation imaging detectors and dosimeters based on the optical reading of the visible photoluminescence in LiF crystals and polycrystalline thin films. They were proposed for soft X-ray imaging at high spatial resolution and, more recently, their use has been successfully applied to advanced diagnostics of proton beams. After proton irradiation of LiF, the emission intensity of the radiation-induced point defects is proportional to the absorbed dose over several orders of magnitude, thus novel solid-state dosimeters with imaging capabilities can be envisaged, although dose values that are typical of clinical radiotherapy are still a challenge. In this brief review, the main experimental results and recent advances concerning radiophotoluminescence of color centers in optically transparent LiF crystals and polycrystalline thin films are presented and discussed in order to highlight the advantages, challenges and limits related to the feasibility of detectors for protontherapy applications.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
