Optical Injection Locking

The great achievements on both digital and analog fiber-optic communications have shown their powerful functions and significant effects on our everyday life. Semiconductor optoelectronics is the major enabling component in optical communications, and has become a wide and vast research field.

Direct modulated lasers, as optical transmitters in fiber-optic communication system, are cost-effective and compact. High performance of direct modulated semiconductor laser is highly desirable in both analog and digital links. One method that can drastically improve the performance of a direct modulated laser is optical injection locking (OIL), which uses a second laser (master laser) to inject photons at a similar wavelength into the transmitter laser (follower laser). The transmitter laser is thus locked (in wavelength and phase) to the master due to the coherent non-linear interaction.

Vertical-cavity surface-emitting lasers (VCSELs) can be grown expitaxialy, which greatly reduce the cost and make on-wafer testing possible. In addition, because of its short cavity length, it has superb single mode behavior. Optical injection locking has been shown to be a very effective technique to improve the performance of VCSELs significantly, thus making it more suitable for RF and wireless communication network.

Ideal device design for further improvement as well as theoretical study of the dynamics to understand the physics behind the phenomena are also underway.

Collaborators:
Professor Markus C. Amann’s group at Technical University of Munich, Germany
Professor Ming C. Wu’s group at University California Berkeley

Referred Journal Papers

• Elaine Wong, Xiaoxue Zhao, Connie J. Chang-Hasnain, Werner Hofmann and Markus C. Amann, “Rayleigh backscattering and Extinction Ratio Study of Optically Injection-Locked 1.55-mm VCSELs,” Electron. Lett. Vol. 43, No.3 pp. 182-183 (2007)
• X. Zhao, Y. Zhou, C. J. Chang-Hasnain, W. Hofmann, and M. C. Amann, "Novel modulated-master injection-locked 1.55-µm VCSELs," Opt. Express 14, 10500-10507 (2006)
• Elaine Wong, Xiaoxue Zhao, Connie J. Chang-Hasnain, Werner Hofmann, Markus C. Amann, “Optically Injection-Locked 1.55-um VCSELs as Upstream Transmitters in WDM-PONs,” Photon. Technl. Lett. 18, pp. 2371 – 2373 (2006)
• Lukas Chrostowski, Xiaoxue Zhao, Connie, J. Chang-Hasnain, “Microwave Performance of Optically Injection-Locked VCSELs,” Invited paper, IEEE Transactions on Microwave Theory and Techniques Special Issue on Microwave Photonics, vol.54, pp788- 796 (2006)
• Xiaoxue Zhao, Lukas Chrostowski, and Connie Chang-Hasnain, “High extinction ratio of injection-locked 1.55 µm VCSELs,” Photon. Technl. Lett. vol.18, pp166-168, (2006)
• L. Chrostowski, X. Zhao, C. J. Chang-Hasnain, R. Shau, M. Ortsiefer, and M.-C. Amann, “50GHz Optically Injection-Locked 1.55 µm VCSELs,” Photon. Technl. Lett. vol.18, pp367-369, (2006)
• X. Zhao, M. Moewe, L. Chrostowski, C.-H. Chang, R. Shau, M. Ortsiefer, M.-C. Amann, and C. J. Chang-Hasnain, "28GHz Optical Injection-Locked 1.55 µm VCSELs," IEE Electron. Lett. vol 40, (2004)

Conference Presentations and Posters

• Hyuk-Kee Sung, Erwin K. Lau, Xiaoxue Zhao, Devang Parekh, Connie J. Chang-Hasnain and Ming C. Wu, “Optically Injection-Locked Optoelectronic Oscillators with Low RF Threshold Gain,” CLEO/QELS 2007
• Elaine Wong, Xiaoxue Zhao and Connie J. Chang-Hasnain, “Novel Fault Monitoring and Localization Scheme in WDM-PONs with Upstream VCSEL transmitters,” OFC 2007
• Elaine Wong, Xiaoxue Zhao, Connie J. Chang-Hasnain, Werner Hofmann and Markus C. Amann, “Extinction Ratio Dependence of 1.55 μm VCSELs Injection-Locked by Modulated Downstream Signals in a WDM-PON,” ECOC poster 2006
• Xiaoxue Zhao, Connie J. Chang-Hasnian, Werner Hofmann and Markus-C. Amann, “Modulation Efficiency Enhancement of 1.55-μm Injection-Locked VCSELs,” International Semiconductor Laser Conference (ISLC) 2006
• Elaine Wong, Xiaoxue Zhao, Connie Chang-Hasnain, Werner Hofmann and Markus-C. Amann, “Uncooled, Optical Injection-Locked 1.55 µm VCSELs for Upstream Transmitters in WDM-PONs,” post-deadline OFC 2006
• Xiaoxue Zhao, Ye Zhou, Connie J. Chang-Hasnain, Werner Hofmann and Markus C. Amann, “Slow and Fast Light Using Master-Modulated Injection-Locked VCSELs,” CLEO/QELS 2006 conference proceedings
• Bala Pesala, Lukas Chrostowski, Wendy Zhao and Connie Chang-Hasnain, “Feedback Tolerance of Injection-Locked VCSELs”, CLEO/QELS 2005 conference proceedings
• Lukas Chrostowski, Xiaoxue Zhao, Connie Chang-Hasnain,Robert Shau, Markus Ortsiefer and Markus-Christian Amann, "50GHz Directly-Modulated Injection-Locked 1.55µm VCSELs", OFC 2005 conference proceedings
• Xiaoxue Zhao, Lukas Chrostowski, and Connie Chang-Hasnain, "Extinction Ratio of Injection Locked VCSELs", IEEE/LEOS Annual Meeting, 2004 Conference Proceedings
• Xiaoxue Zhao, Lukas Chrostowski and Connie Chang-Hasnain, "Dynamic Range Enhancement in 1.55 µm VCSELs using Injection-Locking", International Topical Meeting on Microwave Photonics, 2004 Conference Proceedings
• L. Chrostowski, X. Zhao and C. Chang-Hasnain, R. Shau, M. Ortsiefer, and M.-C. Amann, "Very High Resonance Frequency (>40GHz) Optical Injection-Locked 1.55 µm VCSELs", International Topical Meeting on Microwave Photonics, 2004 Conference Proceedings
• L. Chrostowski, M. Moewe, Wendy Zhao; Chih-Hao Chang; C. Chang-Hasnain, R. Shau, M. Ortsiefer, M.-C. Amann, "39GHz Intrinsic Bandwidth of a 1.55 µm Injection-Locked VCSEL", CLEO 2004 Conference Proceedings