is a free fitting parameter. This fitted line should be a straight line in our log-log plot , where the slope corresponds to the value of~ 0.8 ± 0.1 for XY-8 to be fairly close to one, and this validates that the main decoherence source for XY8 is from the dipolar interaction whose strength scales linearly withdensity since the DROID sequence should decouple thedipolar interaction, but due to other factors like imperfect drive the decoherence timescale still decrease.
, how many spins one can simulate, in numerical simulations. The presence of nearby bath spins leads to a large broadening of the~ 80 MHz . Therefore, with Rabi driving frequency, the applied pulses will have significant imperfections. To better capture this effect in simulation, we incorporate a random static on-site field on each spin drawn from the measured resonance distribution, and average across all different configurations.