{"id":6128,"date":"2012-07-18T22:25:53","date_gmt":"2012-07-18T22:25:53","guid":{"rendered":"https:\/\/mtlsites.mit.edu\/annual_reports\/2012\/?p=6128"},"modified":"2012-07-18T22:25:53","modified_gmt":"2012-07-18T22:25:53","slug":"automated-wavelength-recovery-for-microring-resonators","status":"publish","type":"post","link":"https:\/\/mtlsites.mit.edu\/annual_reports\/2012\/automated-wavelength-recovery-for-microring-resonators\/","title":{"rendered":"Automated Wavelength Recovery for Microring Resonators"},"content":{"rendered":"
Silicon photonics is poised to meet the increasing demand for high-bandwidth, low-power, and densely integrated optical communications in CMOS-compatible environments. Microring resonators in particular have become ubiquitous photonic building blocks that have already been utilized to demonstrate modulators, filters, and switches. However, the large frequency dependence with geometry (~100GHz\/nm) and thermo-optic coefficient (~10GHz\/\u00b0C) innate to silicon microrings threatens to preclude their use in dense wavelength division multiplexed (DWDM) applications, where the channel spacings are tight and temperatures may vary by as much as 15\u00b0C. Several promising solutions to address this challenge have come in the form of low-power (4.4\u00b5W\/GHz) and high-speed thermal tuning, sensor-based thermal compensation, and athermal devices. However, while temperature sensor and athermal solutions address the thermal stability issue, they do not address fabrication based frequency variations. A recent study has leveraged scattering of the microring filters for wavelength locking; however, scattered light based techniques are insufficiently reliable to enable large-scale implementations.<\/p>\n