Single Crystal Sapphire at milli-Kelvin Temperatures: Observation of Electromagnetically Induced Thermal Bistability in High Q-factor Whispering Gallery Modes

Daniel L. Creedon, Michael E. Tobar, Jean-Michel Le Floch +2

Resonance modes in single crystal sapphire ($\alpha$-Al${}_2$O${}_3$) exhibit extremely high electrical and mechanical Q-factors ($\approx 10^9$ at 4K), which are important characteristics…