Application of MgB₂ to Superconducting Radio-Frequency Cavities

Abstract

Advances in the research and development on MgB₂ toward the application to superconducting radio-frequency (SRF) cavities for particle accelerators are reviewed. Evaluations using small flat thin film samples have shown promising results and the techniques to coat the interior of SRF cavities with MgB₂ are being developed. We will probably see some results of standard 1.3-GHz cavities coated with MgB₂ within 5 years. If MgB₂ coated cavities are successfully developed, a new class of SRF cavities operated at ~20 K with cryocoolers will be possible. Such accelerators can be used more easily at 20 K than at 4 K since higher capacity cryocoolers are available and the static heat load is more tolerable. Future applications of such accelerators include, but not limited to, environmental remediation and national security in addition to physics and material science.