Development of vector modulation technique using spin-controlled semiconductor lasers

2021 Fiscal Year Final Research Report

• Project/Area Number: 19H02186
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 21060:Electron device and electronic equipment-related
• Research Institution: Tohoku University
• Principal Investigator: YOKOTA Nobuhide 東北大学, 電気通信研究所, 助教 (00734542)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 面発光レーザ / スピン偏極 / ベクトル変調

Outline of Final Research Achievements

A vector modulation scheme in which both amplitude and phase of light are modulated is promising for next-generation optical communication systems, because it can densely allocate signal points in a complex plane. In this study, the vector modulation of light using an injection-locked semiconductor laser under modulation of electron spin polarization was theoretically confirmed, and a preliminary experimental setup for evaluation of the vector modulation waveforms was developed. Moreover, application of the spin-controlled semiconductor laser to radio over fiber systems and local oscillators in coherent optical communication systems was proposed and demonstrated.

Free Research Field

光エレクトロニクス

Academic Significance and Societal Importance of the Research Achievements

光通信等で用いられる通常の半導体レーザでは電流注入される電子の密度のみが変調され、電子の有するスピン偏極状態の自由度は制御されない。本研究は半導体レーザにおける注入電子のスピン偏極度を高速に変調することが通常の半導体レーザの高速動作限界を突破する切り口になることを明らかにしたものであり、今後の光通信の大容量化や次世代無線通信技術（Beyond 5G）の発展に貢献するものである。