Microwave Photonics Research Laboratory, University of Ottawa, 25 Templeton Street, Ottawa, Ontario, Canada K1N 6N5.
Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, California 93116, USA.
Nat Commun. 2017 May 12;8:15389. doi: 10.1038/ncomms15389.
Mode control in a laser cavity is critical for a stable single-mode operation of a ring laser. In this study we propose and experimentally demonstrate an electrically pumped parity-time (PT)-symmetric microring laser with precise mode control, to achieve wavelength-tunable single-mode lasing with an improved mode suppression ratio. The proposed PT-symmetric laser is implemented based on a photonic integrated circuit consisting of two mutually coupled active microring resonators. By incorporating multiple semiconductor optical amplifiers in the microring resonators, the PT-symmetry condition can be achieved by a precise manipulation of the interplay between the gain and loss in the two microring resonators, and the incorporation of phase modulators in the microring resonators enables continuous wavelength tuning. Single-mode lasing at 1,554.148 nm with a sidemode suppression ratio exceeding 36 dB is demonstrated and the lasing wavelength is continuously tunable from 1,553.800 to 1,554.020 nm.
在激光腔中进行模式控制对于环形激光器的稳定单模运行至关重要。在本研究中，我们提出并实验演示了一种电泵浦的奇偶（PT）对称微环激光器，具有精确的模式控制，可实现波长可调谐的单模激光，同时具有改善的模式抑制比。所提出的 PT 对称激光器基于由两个相互耦合的有源微环谐振器组成的光子集成电路来实现。通过在微环谐振器中集成多个半导体光放大器，可以通过精确控制两个微环谐振器中增益和损耗之间的相互作用来实现 PT 对称性条件，并且在微环谐振器中集成相位调制器可以实现连续波长调谐。在 1,554.148nm 处实现了超过 36dB 的边模抑制比的单模激光，并且激光波长可连续从 1,553.800nm 调谐至 1,554.020nm。
