Energy-efficient on-chip optical diode based on the optomechanical effect.

We propose and experimentally demonstrate an energy-efficient optical diode based on the optomechanical effect. The optical signals could transmit during forward propagation while be blocked during backward propagation. When launching optical signal with a low power of 4.0 mW, the maximum resonance red-shift of the asymmetric silicon microring resonator (MRR) could be up to 0.74 nm, in this case, a forward-backward nonreciprocal transmission ratio (NTR) of 12.7 dB has been achieved. The 10-dB and 5-dB operation bandwidths are 0.08 nm and 0.24 nm, respectively. The operating bandwidth could be continuously tuned theoretically by changing the input power.