Kavli Affiliate: Tomiyoshi Haruyama | Summary:We have measured the mechanical loss of a dielectric multilayer reflective coating (ion-beam sputtered SiO$_2$ and Ta$_2$O$_5$) in cooled mirrors. The loss was nearly independent of the temperature (4 K $sim$ 300 K), frequency, optical loss, and stress caused by the coating, and the details of the manufacturing processes. The […]