Theoretical analysis of nonlinear optical response in Rashba electron system with broken time inversion symmetry

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K03527
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 13030:Magnetism, superconductivity and strongly correlated systems-related
• Research Institution: Toyo University
• Principal Investigator: Shibata Junya 東洋大学, 理工学部, 教授 (20391972)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: スピントロニクス / 電磁交差相関現象 / 運動量依存スピン軌道相互作用 / 負屈折現象 / 後進波現象 / 旋光性現象

Outline of Final Research Achievements

The purpose of this study is to theoretically extend the electric-magnetic-optical response from the linear response regime to the nonlinear response regime, focusing on the system with momentum-dependent spin-orbit interaction due to the violation of the spatial inversion symmetry, and to find new optical phenomena caused by the cross-correlation effect. For this purpose, we analyze the optical conductivity and the spin polarizability of the system under consideration for all frequency regions. In addition, we analyzed the peculiar optical phenomena caused by the momentum-dependent spin-orbit interaction (negative refraction, backward wave, and optical activity), and showed that a large response (large negative refraction angle, large rotation of the polarization plane, etc.) can be obtained in a certain frequency region.

Free Research Field

物性理論物理学

Academic Significance and Societal Importance of the Research Achievements

近年、我々が扱う情報量は日々増加しており、大量のデータ記録や高速処理、さらには、情報処理に伴うエネルギー消費量の抑制といった社会的要請に応えていく為には、新規デバイスの開発に必要不可欠な新たな物質特性の探索, その特性を活かした新たな機能の創出が必要とされる。本研究では、物質特性を探る上で欠かせない物質の電気-磁気-光学応答に関して、近年注目されている電磁交差相関効果を基軸に理論的に解析を遂行し、特に、空間反転対称性の破れに伴う運動量依存スピン軌道相互作用が生じる系の電流-スピン応答の特性を全ての振動数領域において明らかにすることができた。