Study on a narrow linewidth frequency-stabilized laser for coherent optical communication

2015 Fiscal Year Final Research Report

• Project/Area Number: 26706016
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Optical engineering, Photon science
• Research Institution: Tohoku University
• Principal Investigator: KASAI KEISUKE 東北大学, 電気通信研究所, 助教 (80534495)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: レーザー / 周波数安定化 / ファブリーペロー共振器 / コヒーレント光通信

Outline of Final Research Achievements

With the aim of applying to next generation ultra-multilevel coherent optical communication, I have developed a 1.5 um frequency-stabilized laser with a high optical signal-to-noise ratio, a narrow linewidth, and low intensity noise characteristics. As an optical frequency standard, I have developed a compact and stable Fabry-Perot etalon with a linewidth as narrow as 60 MHz, which was made of a low expansion complex material based on crystal. As a coherent laser for frequency stabilization, I have constructed a 295 mW output, single frequency fiber laser with a linewidth of 5 kHz, relative intensity noise (RIN) of less than -120 dB/Hz. Furthermore, a laser diode with a linewidth of 8 kHz and a RIN of -130 dB/Hz has been developed. By stabilizing their frequency to the peak of etalon, I have successfully realized a low noise coherent laser with a frequency stability of 1E-12. In addition, I have applied these lasers to coherent optical transmission and demonstrated their usefulness.

Free Research Field

光通信工学