Study on Raman gain induced by incoherent light in high quality photonic crystal devices

2021 Fiscal Year Final Research Report

• Project/Area Number: 18H01479
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 21050:Electric and electronic materials-related
• Research Institution: Osaka Prefecture University
• Principal Investigator: Takahashi Yasushi 大阪府立大学, 工学(系)研究科(研究院), 准教授 (20512809)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: ラマンレーザ / 高Q値ナノ共振器 / シリコンフォトニクス / 誘導ラマン散乱

Outline of Final Research Achievements

We have studied the application of a nanocavity Raman silicon laser. The Raman scattering spectra from the nanocavity excited by incoherent light are compared with the spectra excited by coherent light. Although promising results were obtained for the cw laser oscillation, it was not possible to inject a sufficient amount of light into the nanocavity for the cw oscillation with incoherent light. It is effective for Raman laser with incoherent light to decrease the laser threshold. We have designed the nanocavity with the higher Q factors by the machine learning, in which the threshold of a sub 100 microwatt threshold was obtained. This threshold is less than half of the conventional value. In addition, we have also realized the Raman silicon laser with a shorter wavelength band that can decrease the threshold by two times. As an unexpected results, we have demonstrated a promising application of the development for the space charge sensor with incoherent light excitation.

Free Research Field

シリコンフォトニクス

Academic Significance and Societal Importance of the Research Achievements

実用的なシリコンレーザ開発は科学者の夢である。シリコンラマンレーザは、唯一の室温連続発振するシリコンレーザである。研究代表者が開発したシリコンラマンレーザは、インテルが開発したレーザの1万分の１以下のエネルギー閾値と装置サイズを持つ。半世紀の間、全てのラマン増幅デバイスは、レーザ光を誘導ラマン利得の発生に用いてきたが、シリコンのラマンバンド幅は狭い。広帯域ラマン利得の発生が応用では重要である。そこで、インコヒーレント光を用いる手法を、高品質サンプルと、顕微分光測定により調べた。本研究が目指す広帯域でレーザ発振するシリコンラマンレーザチップは、IT技術の大幅な省エネ化と高速化をもたらすだろう。