We propose and realize a bandwidth and wavelength-tunable all-optical filter with high tuning efficiency based on double opto-mechanical microring resonators (MRRs) assisted Mach-Zehnder interferometer (MZI) structure, which is beneficial to achieve high extinction ratio and shape factor. As the optical field gradient is largely enhanced in the free-hanging MRRs, the opto-mechanical effect could be excited by low power consumption. By injecting the corresponding low resonance powers, the drop transmission of each MRR could be flexibly tuned based on the opto-mechanical effect. Consequently, the synthetic transmission of the microring-assisted MZI could be efficiently manipulated. The results show that by injecting pump powers of 0.40 mW and 1.84 mW, the bandwidth and wavelength of the all-optical filter could be tuned from 0.17 nm to 0.30 nm, and from 1550.09 nm to 1550.60 nm respectively with maintaining a high extinction ratio of 38 dB and a small passband ripple of 1 dB. Especially, the tuning efficiencies of bandwidth and wavelength could realize up to 0.325 nm/mW and 0.277 nm/mW, respectively. The proposed optical filter has dominant advantages of high tuning efficiencies and extinction ratios, small passband ripple and compact footprint, which has significant applications in on-chip all-optical systems.

By utilizing two cascaded all-silicon opto-mechanical microring resonators (MRRs), an energy-efficient optical diode with high nonreciprocal transmission ratios (NTRs) is proposed and experimentally realized. The optical diode is composed of an allpass opto-mechanical MRR and an add-drop opto-mechanical MRR. Due to the largely enhanced interaction between the photons and the suspended structure, the opto-mechanical effect can be dramatically improved. With injecting low optical powers, the optical gradient force can be effectively aroused in the opto-mechanical MRRs, which would arise nanometer scale waveguide deformations and the significant spectrum red-shifts of the rings. The opto-mechanical effect would cause different red-shifts of the two MRR resonances in the forward and backward transmissions, which contributes to realizing the nonreciprocal transmissions. The experimental results show that with −4.2 dBm power consumption, the optical diode can achieve high NTRs approach 41.8 dB. Due to the dominant advantages of complementary metal oxide semiconductor (COMS) compatibility, high NTRs (41.8 dB), low power consumption (−4.2 dBm) and compact size (0.015 mm 2), the device has remarkable applications in on-chip signal processing systems.