Gain Incorporated Split-Ring Resonator Structures for Active Metamaterials
Testing of the active SRR incorporating gain elements. (a) Testing setup for the circulator based aSRR designs. The passive SRR is connected to the circulator and amplifier block (Figure 6(a)) via a coax cable to minimize the impact on the effective testing region of the electromagnetic field between two probe antennas. (b) Amplitude spectral response shown as the relative spectral intensity of versus the probing frequency. (c) Phase spectral response shown as the calibrated and unwrapped phase of versus the probing frequency.