量子シミュレーションにおけるストライプ形成の兆候(Quantum simulation: First signs of stripe formation)

ad

2025-01-17 ミュンヘン大学(LMU)

ルートヴィヒ・マクシミリアン大学ミュンヘンとマックス・プランク量子光学研究所の研究チームが、冷却原子を用いたフェルミ・ハバードモデルで、超伝導に関連する「ストライプ形成」の初期段階を確認しました。この研究では、量子ガス顕微鏡を用い、スピンと電荷密度における相関を観察。特定の温度で「穴」の配置が非ランダムな一列構造を示すことを確認し、これが高温超伝導研究の新たな知見をもたらすとしています。

<関連情報>

混合次元冷原子フェルミ・ハバード系における個々の縞の形成 Formation of individual stripes in a mixed-dimensional cold-atom Fermi–Hubbard system

Dominik Bourgund,Thomas Chalopin,Petar Bojović,Henning Schlömer,Si Wang,Titus Franz,Sarah Hirthe,Annabelle Bohrdt,Fabian Grusdt,Immanuel Bloch & Timon A. Hilker
Nature  Published:01 January 2025
DOI:https://doi.org/10.1038/s41586-024-08270-7

量子シミュレーションにおけるストライプ形成の兆候(Quantum simulation: First signs of stripe formation)

Abstract

The relation between d-wave superconductivity and stripes is fundamental to the understanding of ordered phases in high-temperature cuprate superconductors1,2,3,4,5,6. These phases can be strongly influenced by anisotropic couplings, leading to higher critical temperatures, as emphasized by the recent discovery of superconductivity in nickelates7,8,9,10. Quantum simulators with ultracold atoms provide a versatile platform to engineer such couplings and to observe emergent structures in real space with single-particle resolution. Here we show, to our knowledge, the first signatures of individual stripes in a cold-atom Fermi–Hubbard quantum simulator using mixed-dimensional (mixD) settings. Increasing the energy scale of hole–hole attraction to the spin exchange energy, we access the interesting crossover temperature regime in which stripes begin to form11. We observe extended, attractive correlations between hole dopants and find an increased probability of forming larger structures akin to individual stripes. In the spin sector, we study correlation functions up to the third order and find results consistent with stripe formation. These observations are interpreted as a precursor to the stripe phase, which is characterized by interleaved charge and spin density wave ordering with fluctuating lines of dopants separating domains of opposite antiferromagnetic order12,13,14.

1700応用理学一般
ad
ad
Follow
ad
タイトルとURLをコピーしました