Figure 1

Overview of the SAW devices (a) The magnitude of \(S_{11}\) across the full stopband of the device taken at 10 mK. Modes are centered at 690 MHz with a 1.7 MHz FSR. (b), (c) Optical microscope images of the SAW features: image (b) details the full SAW device with central IDT and Bragg mirrors on either side, image (c) zooms into the IDT fingers. (d), (f) Zoomed in reflection measurement (blue) and fit to a Lorentzian (red) of the first SAW mode centered at 688.4 MHz after normalization. Magnitude (d), phase (e) and real vs. imaginary parts (f) of \(S_{11}\) are plotted for the same mode. Fit to the mode finds \(Q_i = 6.8\times 10^3\) and \(Q_e = 1.4\times 10^4\).