セミナー案内

日時
    
6月20日 (水), 13:30-
場所
京都大学理学部 5号館 413
講演者
Dr. Jun Ishizuka
(Condensed Matter Theory Group)
タイトル
"Magnetic multipole fluctuation and superconductivity in locally noncentrosymmetric crystal"
備考欄 (アブストラクト等)

Abstract:
Recent intensive research in locally noncenrosymmetric (NCS) crystals has revealed that odd-parity multipole order would be realized in several materials, such as BaMn2As2 [1], Sr2IrO4 [2], Cd2Re2O7 [3], and SrTiO3 [4]. These materials have been studied from the view point of the odd-parity multipole. Superconductivity near the odd-parity electromagnetic multipole order may invokes an unconventional pairing mechanism induced by an odd-parity multipole fluctuation. Intriguingly, because the antiferromagnetic (AFM) order in locally NCS crystals with the sublattice-dependent antisymmetric spin-orbit coupling (ASOC) stabilizes the odd-parity multipole order, AFM-fluctuation-induced superconductivity will naturally reveal the superconductivity owing to the odd-parity fluctuation. However, theoretical studies based on microscopic models have not been conducted, except for a few works [5]. Here, we study a microscopic model and show that two odd-parity superconductivities are realized near the parity-violating magnetic order.


Reference:
[1] H. Watanabe and Y. Yanase, Phys. Rev. B 96, 064432 (2017).
[2] L. Zhao et al, Nat. Phys. 12, 32 (2016).
[3] L. Fu, Phys. Rev. Lett. 115, 026401 (2015).
[4] C. W. Rischau et al, Nat. Phys. 13, 643 (2017).
[5] V. Kozii and L. Fu Phys. Rev. Lett 115, 207002 (2015).