Li Nanxi, Su Zhan, Salih Magden E, Poulton Christopher V, Ruocco Alfonso, Singh Neetesh, Byrd Matthew J, Bradley Jonathan D B, Leake Gerald, Watts Michael R
Research Laboratory of Electronics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
College of Nanoscale Science and Engineering, University at Albany, 1400 Washington Avenue, Albany, New York 12203, USA.
Appl Phys Lett. 2017 May 22;110(21):211105. doi: 10.1063/1.4984022.
In an optical interconnect circuit, microring resonators (MRRs) are commonly used in wavelength division multiplexing systems. To make the MRR and laser synchronized, the resonance wavelength of the MRR needs to be thermally controlled, and the power consumption becomes significant with a high-channel count. Here, we demonstrate an athermally synchronized rare-earth-doped laser and MRR. The laser comprises a SiN based cavity covered with erbium-doped AlO to provide gain. The low thermo-optic coefficient of AlO and SiN and the comparable thermal shift of the effective index in the laser and microring cross-sections enable lasing and resonance wavelength synchronization over a wide range of temperatures. The power difference between matched and unmatched channels remains greater than 15 dB from 20 to 50 °C due to a synchronized wavelength shift of 0.02 nm/°C. The athermal synchronization approach reported here is not limited to microring filters but can be applied to any SiN filter with integrated lasers using rare earth ion doped AlO as a gain medium to achieve system-level temperature control free operation.
在光互连电路中，微环谐振器（MRR）常用于波分复用系统。为使MRR与激光器同步，需要对MRR的谐振波长进行热控制，并且随着通道数增加，功耗会变得很大。在此，我们展示了一种非热同步的掺稀土激光器和MRR。该激光器包括一个基于SiN的腔，其上覆盖掺铒AlO以提供增益。AlO和SiN的低热光系数以及激光器和微环横截面中有效折射率相当的热位移，使得在很宽的温度范围内能够实现激光发射和谐振波长同步。由于0.02 nm/°C的同步波长偏移，在20至50°C范围内，匹配通道和不匹配通道之间的功率差保持大于15 dB。这里报道的非热同步方法不仅限于微环滤波器，还可应用于任何以掺稀土离子的AlO作为增益介质且集成了激光器的SiN滤波器，以实现系统级无温度控制操作。
