Figure 2

Time-domain and frequency-domain waveforms of the input and output signals of the nonlinear medium.

(a) Time-domain input waveform along the forward and reverse directions after passing through the lossy and gain media they meet first. (b) The amplitude dependence of the nonlinear medium. (c,d) show the time-domain signal after passing through the nonlinear medium along the reverse and forward directions respectively. The insets are the corresponding spectrum components. Along the reverse direction, the wave has its peak clipped off when passing through the nonlinear medium and the amplitude of transmitted fundamental wave is then largely diminished. The wave travelling along the positive direction is not affected by the nonlinear medium due to its small amplitude.