Control of a single spin state by a circularly polarized photon in a semiconductor-based three-dimensional chiral photonic crystal cavity

2020 Fiscal Year Final Research Report

• Project/Area Number: 16H06085
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Electron device/Electronic equipment
• Research Institution: Kyoto Institute of Technology
• Principal Investigator: Takahashi Shun 京都工芸繊維大学, 電気電子工学系, 助教 (60731768)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: フォトニック結晶

Outline of Final Research Achievements

Cavities for circularly polarized light with a high quality was designed by numerical calculations for semiconductor-based three-dimensional chiral photonic crystals which are able to control circularly polarized light. Based on this design, a three-dimensional chiral woodpile structure was fabricated by semiconductor nano-fabrication methods including a micro-manipulation technique. For this sample containing quantum dots, micro-photoluminescence measurements at low temperature revealed a cavity mode for circularly polarized light and indicated the Purcell effect between a circularly polarized photon and an exciton in a quantum dot. Though additional accurate measurements are required for the single photon detection, this result suggests the control of a single spin through a circularly polarized photon in the cavity.

Free Research Field

電子デバイス・電子機器

Academic Significance and Societal Importance of the Research Achievements

一般にスピンの制御は外部磁場を必要とするが、本研究では、左回り円偏光と右回り円偏光が、上向き電子スピンと下向き電子スピンにそれぞれ一対一で対応することを利用して、ナノスケールで作製した三次元らせん構造に円偏光を閉じ込めることで、構造内部のスピンを効率的に制御することに成功した。実用に不向きな外部磁場の代わりに、幾何学的なカイラリティによってスピンを制御できるため、スピンや偏光の高効率な初期化や高感度センサなど、フォトニクスおよびスピントロニクスへの応用が期待できる。