Fig. 2: Quadratic cavity simulton enhancement mechanism.

a Theoretical behavior of near-threshold sensing, wherein the addition of sample causes an increase in threshold, resulting in a decrease in signal power at the sensing point. b The corresponding signal enhancement grows asymptotically as threshold is approached. c Experimentally measured input-output power relationships for the simulton (orange) and conventional (pink) regimes show the extremely high slope efficiency and high threshold of the simulton, suggesting its potential for near-threshold sensing with high SNR. Solid lines capture the trends through linear fits of the experimental data while the orange, dashed line shows the corresponding simulton simulation.