抄録
An angle-resolved photoemission spectroscopy (ARPES) study is reported on a Mott insulator NiGa2S4 in which Ni2+ (S=1) ions form a triangular lattice and the Ni spins do not order even in its ground state. The first ARPES study on the two-dimensional spin-disordered system shows that low-energy hole dynamics at high temperatures is characterized by wave vectors QE which are different from wave vectors QM dominating low-energy spin excitations at low temperatures. The unexpected difference between QE and QM is deeply related to charge fluctuation across the Mott gap in the frustrated lattice and is a key issue to understand the spin-disordered ground states in Mott insulators.
本文言語 | English |
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論文番号 | 226404 |
ジャーナル | Physical Review Letters |
巻 | 104 |
号 | 22 |
DOI | |
出版ステータス | Published - 2010 6月 3 |
外部発表 | はい |
ASJC Scopus subject areas
- 物理学および天文学(全般)