Exploration of superconducting materials using first-principles calculations

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K03442
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 13010:Mathematical physics and fundamental theory of condensed matter physics-related
• Research Institution: Tohoku University
• Principal Investigator: Koretsune Takashi 東北大学, 理学研究科, 准教授 (90391953)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 超伝導 / 第一原理計算 / 物質探索

Outline of Final Research Achievements

We have conducted research to establish a technique to reproduce superconducting transition temperatures of hydrogen compounds and to explore new superconducting materials. We found that the superconducting transition temperature of LaH10 can be explained by quantum effects originating from the quantum fluctuation of hydrogen, and showed that the transition temperature can be reproduced quantitatively. We also studied hydrides containing sulfur and carbon, which were experimentally pointed out as possible room-temperature superconductors, and clarified that the room-temperature superconductivity cannot be explained by the conventional mechanism. We believe that these results will be indispensable knowledge in the exploration of new superconducting materials with higher transition temperatures.

Free Research Field

物性理論

Academic Significance and Societal Importance of the Research Achievements

転移温度が室温にせまる超伝導体の転移温度を，経験的なパラメータを一切用いず，基本方程式と結晶構造のみに立脚して定量的に説明できることを示したこと，また，そこでは水素の量子効果が重要な役割を果たしていることを示したことは，今後の水素化合物超伝導体探索において欠かせない知見である。本手法は従来型の超伝導体であれば他の超伝導体にも適用可能であり，今後，様々な超伝導体探索に適用が期待される。