Figure 1

(a) Optical Q factor (2.5 × 10⁷), pump wavelength of 1550 nm and pump power of 0.5 mW and (b) Mechanical Q factor (4 × 10³) for a MBR of a diameter ~460 μm and wall thickness of ~5.5 μm, measured at pump wavelength of 1550 nm and pump power of 80 mW.