Theory of light scattering by charge and orbital nematic fluctuations

2014 Fiscal Year Final Research Report

• Project/Area Number: 25800206
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics II
• Research Institution: National Institute for Materials Science
• Principal Investigator: YAMASE Hiroyuki 独立行政法人物質・材料研究機構, 超伝導物性ユニット, 主幹研究員 (10342867)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: 物性理論 / 強相関電子系 / 光物性 / ラマン散乱 / ネマチック / 自発的対称性の破れ / 銅酸化物超伝導 / 鉄系超伝導

Outline of Final Research Achievements

An electronic nematic state breaks orientational symmetry of the system but retains the other symmetries. This instability is driven by spontaneous symmetry breaking, as in the case of superconductivity and magnetism. Hence it is fundamentally important in materials science to establish the existence of the electronic nematic state. Here, motivated by an insight that electronic nematic correlation functions can be measured directly by Raman scattering, we study nematic fluctuations associated with orbital and spin, which are vigorously discussed in iron-based superconductors. We establish a theory of Raman scattering by both fluctuations and also propose a new mechanism of high-temperature superconductivity due to orbital fluctuations.

Free Research Field

物性理論