Hi, I just started out with the piezoelectric devices interface in COMSOL. I want to create a resonator using A piezo material like Aluminum nitride and plot the abs(pzd.Y11) vs frequency around the resonant frequency of a particular mode of vibration. I used the eigenfrequency analysis to find the resonant modes and used frequency domain analysis to plot the 1D graph of admittance vs. frequency around the first eigen frequency (around 3.25e6 Hz). But all I'm getting is a straight line for abs, real and imag(pzd.Y11). I tried decreasing frequency step size to just 100Hz, but I'm still getting a flat response. There is no change if I add/remove damping. But in a 1D plot like that of stored energy vs. freq., I am getting a peak at the resonant frequency. Can anyone help? I used the default values in the Piezo coefficient matrices after verifying that they were more or less same as that of literature. Thanks!