Table 1 Resonator EPR signal characteristics calculated and measured using a power saturation measurement of a lithium phthalocyanine point sample.

Dimensions of the resonators and further experimental details are provided in the Supplementary Materials.

GeometryUnsat.
signal
Sat.
signal
Eff.
η
Q0-value
Meas.
ηQ0
Calc.Meas.Calc.Meas.
Bruker MD5W11.01.01.01.06.12 × 10−666501.0
Bruker MS31.51.21.01.079.6 × 10−66001.17
PMR RO6010LM4.41.20.91.24.63 × 10−3616.94
PMR sapphire18.613.33.93.84.63 × 10−318120.59
Microhelix35.728.26.15.76.63 × 10−322035.84