フルヤ　シュンスケ   FURUYA Shunsuke   古谷　峻介    所属   埼玉医科大学  医学部 教養教育    職種   専任講師
論文種別	学術雑誌(原著)
言語種別	英語
査読の有無	査読あり
表題	Control of superexchange interactions with DC electric fields
掲載誌名	正式名：Physical Review Research ISSNコード：/2643-1564
出版社	American Physical Society ({APS})
巻・号・頁	3(3)
著者・共著者	Shunsuke C. Furuya,Kazuaki Takasan,Masahiro Sato
発行年月	2021/07/19
概要	We discuss DC electric-field controls of superexchange interactions. We first present generic results about antiferromagnetic and ferromagnetic superexchange interactions valid in a broad class of Mott insulators, where we also estimate typical field strength to observe DC electric-field effects: similar to 1 MV/cm for inorganic Mott insulators such as transition-metal oxides and similar to 0.1 MV/cm for organic ones. Next, we apply these results to geometrically frustrated quantum spin systems. Our theory widely applies to (quasi-)two-dimensional and thin-film systems and one-dimensional quantum spin systems on various lattices such as square, honeycomb, triangular, and kagome ones. In this paper, we give our attention to those on the square lattice and on the chain. For the square lattice, we show that DC electric fields can control a ratio of the nearest-neighbor and next-nearest-neighbor exchange interactions. In some realistic cases, DC electric fields make the two next-nearest-neighbor interactions nonequivalent and eventually turns the square-lattice quantum spin system into a deformed triangular-lattice one. For the chain, DC electric fields can induce singlet-dimer and Haldane-dimer orders. We show that the DC electric-field-induced spin gap proportional to vertical bar E vertical bar(2/3) in the Heisenberg antiferromagnetic chain will reach similar to 10% of the dominant superexchange interaction in the case of a spin-chain compound KCuMoO4(OH) when the DC electric field of similar to 1 MV/cm is applied.
DOI	10.1103/PhysRevResearch.3.033066
ORCIDのPut Code	97183903