Fig. 4
From: Zero-field edge plasmons in a magnetic topological insulator
Effect of temperature and microwave power. a, b Frequency response ΔS 21 and ΔS 23 with increasing microwave power applied to the excitation port. For these measurements T ~ 20 mK. In c, d the dependence of ΔS 21 and ΔS 23 is measured as a function of cryostat temperature while the applied port power is kept low at −87 dBm. In a–f, all the data are taken at zero applied magnetic field after the sample has been magnetised with M z  = −1. Akin to Figs. 2 and 3, the same pre-magnetisation background taken at constant power and cryostat base temperature is subtracted from each of the 2D plots. The colour scale represents ΔS (dB). e, f 1D cuts through the colour plots of ΔS 23 in b, d. The colour bar in e shows power (dB), while the colour bar in f indicates temperature (mK)
