Researchs On On-chip Integrated Microwave Photonic Devices Based On The Silicon Microring Resonator

Owing to the dramatical development of fiber-based optical signal communication and processing,great progress has been achieved in the first generation of Microwave Photonics.However,the drawbacks such as large power consumption and large size is still hard to be effectively solved.In order to minimize the power consumption and device size,now people are focusing on the second generation of Microwave Photonics i.e.,Integrated Microwave Photonics(IMWP).Among all the integrated platforms,silicon-based platform has attracted great interest due to its own distinct advantages on low cost,small size,high integration,flexible tunability and CMOS compatible,and plays an irreplaceable role in IMWP.Silicon-based microring is a key component of silicon integrated systems,it has been favored by lots of researchers owing to the significant advantages in nonlinear optics and spectral tuning.It has been widely used to design lasers,tunable optical/microwave photonic filter,large scale optical switch array and high-speed optical modulator.Based on silicon microring,we focus the research field on all-optical signal processing and microwave photonics,the detailed is shown as below:(1)We give a brief introduction of the birth and development of IMWP,and we detailly introduce the development of integrated microwave photonic filter(IMPF).Moreover,we detailly describe the application of Silicon Photonics in IMPF,including some relevant representatives of both foreign and domestic research groups and the issues which are urgently needed to be solved.(2)We give a brief theoretical analysis of microring.Based on the physical meaning,we give a detailed introduction of different working conditions for a microring.Then we summarsize the tuning methods for a microring,and we detailly describe the fabrication processes and the testing method for a microring in the laboratory.(3)By optimizing the structure of a microring,a silicon microring is fabricated with an ultra-high Q of 1.14×106.The FSR of the microring is as large as 40 GHz,which could satisfy the demands of actual optical communication and signal processing.By utilizing the ultra-high Q silicon microring,an ultra-narrowband(170 MHz)microwave photonic filter is demonstrated,the full width at half-maximum bandwidth of which is much smaller that other works which utilize the silicon micro-resonators.The microwave photonic has distinct advantages on CMOS compatibility,ultra-narrowband,large tuning range,high rejection ratio and small size.Last we briefly describe the application of the microwave photonic filter on integrated optoelectronic oscillator.(4)A silicon-based multi-ports tunable optical circulator is demonstrated by utilizing thermo-optical effect.The device has distinct advantages on simple fabrication process,tunable,numerous ports and large extinction ratio.Then we theoretically analyze the opto-mechanical effect in a microring,and demonstrated an energy-efficient silicon optical diode,this device is CMOS compatible and with a low power consumption.The integration of optical nonreciprocal devices could greatly promote the full integration of microwave photonic filters.