Discovery of charge density wave in a kagome lattice antiferromagnet

Nature, Journal Year: 2022, Volume and Issue: 609(7927), P. 490 - 495

Published: Sept. 14, 2022

Language: Английский

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Coexistence of superconductivity with partially filled stripes in the Hubbard model

Science, Journal Year: 2024, Volume and Issue: 384(6696)

Published: May 9, 2024

The Hubbard model is an iconic in quantum many-body physics and has been intensely studied, especially since the discovery of high-temperature cuprate superconductors. Combining complementary capabilities two computational methods, we found superconductivity both electron- hole-doped regimes two-dimensional with next-nearest-neighbor hopping. In electron-doped regime, was weaker accompanied by antiferromagnetic Néel correlations at low doping. strong on side coexisted stripe order, which persisted into overdoped region hole-density modulation. These orders varied fillings between 0.6 0.8. Our results suggest applicability next-nearest hopping for describing high-transition temperature (

Language: Английский

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Formation of individual stripes in a mixed-dimensional cold-atom Fermi–Hubbard system

Nature, Journal Year: 2025, Volume and Issue: 637(8044), P. 57 - 62

Published: Jan. 1, 2025

Abstract The relation between d -wave superconductivity and stripes is fundamental to the understanding of ordered phases in high-temperature cuprate superconductors 1–6 . These can be strongly influenced by anisotropic couplings, leading higher critical temperatures, as emphasized recent discovery nickelates 7–10 Quantum simulators with ultracold atoms provide a versatile platform engineer such couplings observe emergent structures real space single-particle resolution. Here we show, our knowledge, first signatures individual cold-atom Fermi–Hubbard quantum simulator using mixed-dimensional (mixD) settings. Increasing energy scale hole–hole attraction spin exchange energy, access interesting crossover temperature regime which begin form 11 We extended, attractive correlations hole dopants find an increased probability forming larger akin stripes. In sector, study correlation functions up third order results consistent stripe formation. observations are interpreted precursor phase, characterized interleaved charge density wave ordering fluctuating lines separating domains opposite antiferromagnetic 12–14

Language: Английский

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Cuprate superconductors as viewed through a striped lens

Advances In Physics, Journal Year: 2020, Volume and Issue: 69(4), P. 437 - 509

Published: Oct. 1, 2020

Understanding the electron pairing in hole-doped cuprate superconductors has been a challenge, particular because "normal" state from which it evolves is unprecedented. Now, after three and half decades of research, involving wide range experimental characterizations, possible to delineate clear consistent story. It starts with doping holes into charge-transfer insulator, resulting in-gap states. These states exhibit pseudogap competition between antiferromagnetic superexchange J nearest-neighbor Cu atoms (a real-space interaction) kinetic energy doped holes, which, absence interactions, would lead extended Bloch-wave whose occupancy characterized reciprocal space. To develop some degree coherence on cooling, spin charge correlations must self-organize cooperative fashion. A specific example emergent order that stripes, as observed La2−xBaxCuO4. While stripe frustrates bulk superconductivity, nevertheless develops superconducting an unusual character. The antiphase stripes decouples them can be viewed hole-doped, two-leg, spin-12 ladders. Established theory tells us scale comparable singlet-triplet excitation energy, ∼J/2, achieve order, pair neighboring ladders phase order. In presence Josephson coupling pair-density-wave superconductivity. Alternatively, in-phase superconductivity requires have gap, empirically limits coherent gap. Hence, cuprates involves compromise scale, maximized at x∼18, coherence, optimized x∼0.2. understand further details, necessary take account local variation hole density dopant disorder poor screening long-range Coulomb interactions. At large doping, wins out over J, regions intertwined become sparse, disappears. there are few mysteries remain resolved, I believe this story captures essence cuprates.

Language: Английский

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Stripes and spin-density waves in the doped two-dimensional Hubbard model: Ground state phase diagram

Physical Review Research, Journal Year: 2022, Volume and Issue: 4(1)

Published: March 28, 2022

We determine the spin and charge orders in ground state of doped two-dimensional (2D) Hubbard model its simplest form, namely with only nearest-neighbor hopping on-site repulsion. At half-filling, is known to be an anti-ferromagnetic Mott insulator. Doping insulators believed relevant superconductivity observed cuprates. A variety candidates have been proposed for 2D model. recent work employing a combination several state-of-the-art numerical many-body methods, established stripe order as near $1/8$ doping at strong interactions. In this work, we apply one these cutting-edge constrained-path auxiliary field quantum Monte Carlo method self-consistently optimized gauge constraints, systematically study function interaction strength. With careful finite size scaling based on large-scale computations, map out phase diagram terms order. find that modulated antiferromagnetic persists from half-filling about $1/5$ doping. lower strengths or larger doping, ordered states are best described spin-density waves, essentially delocalized holes modest oscillations correlations. When correlations stronger (large small doping), they states, more localized node both cases, wavelength consistent so-called filled stripes pure

Language: Английский

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Intertwined spin, charge, and pair correlations in the two-dimensional Hubbard model in the thermodynamic limit

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(7)

Published: Feb. 9, 2022

The high-temperature superconducting cuprates are governed by intertwined spin, charge, and orders. While various state-of-the-art numerical methods have demonstrated that these phases also manifest themselves in doped Hubbard models, they differ on which is the actual ground state. Finite-cluster typically indicate stripe order dominates, while embedded quantum-cluster methods, access thermodynamic limit treating long-range correlations with a dynamical mean field, conclude superconductivity does. Here, we report observation of fluctuating spin charge stripes single-band model using quantum Monte Carlo cluster approximation (DCA) method. By resolving both orders DCA, demonstrate survive limit. This discovery provides an opportunity to study influence model's pairing within unified framework. Using this approach, find evidence for pair-density-wave whose strength correlated stripes.

Language: Английский

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Temperature Dependence of Spin and Charge Orders in the Doped Two-Dimensional Hubbard Model

Physical Review X, Journal Year: 2023, Volume and Issue: 13(1)

Published: Jan. 24, 2023

State-of-the-art numerical techniques suggest that charge order in the 2D Hubbard model sets at a nonzero temperature, answering major open question physics of this paradigmatic quantum materials.

Language: Английский

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Superconducting stripes induced by ferromagnetic proximity in an oxide heterostructure

Nature Physics, Journal Year: 2024, Volume and Issue: 20(6), P. 957 - 963

Published: March 11, 2024

Language: Английский

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Discovery of a long-ranged charge order with 1/4 Ge1-dimerization in an antiferromagnetic Kagome metal

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: July 24, 2024

Abstract Exotic quantum states arise from the interplay of various degrees freedom such as charge, spin, orbital, and lattice. Recently, a short-ranged charge order (CO) was discovered deep inside antiferromagnetic phase Kagome magnet FeGe, exhibiting close relationships with magnetism. Despite extensive investigations, CO mechanism remains controversial, mainly because behavior hinders precise identification superstructure. Here, combining multiple experimental techniques, we report observation long-ranged in high-quality FeGe samples, which is accompanied first-order structural transition. With these distorted 2 × superstructure characterized by strong dimerization along c -axis 1/4 Ge1-sites Fe 3 Ge layers, response to that, in-plane modulations are induced. Moreover, show that previously reported might be related large occupational disorders at Ge1-site, upsets equilibrium state ideal 1 structure very energies, inducing nanoscale coexistence two phases. Our study provides important clues for further understanding properties helps identify mechanism.

Language: Английский

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Pair density wave in the doped three-band Hubbard model on two-leg square cylinders

Physical review. B./Physical review. B, Journal Year: 2023, Volume and Issue: 107(21)

Published: June 7, 2023

A pair density wave (PDW) is a superconducting (SC) state with spatially modulated order parameter. Although much known about the properties of PDW state, its realization in microscopic models divergent susceptibility has been challenging. Here we report density-matrix renormalization group study three-band Hubbard model (also as Emery model) for cuprates on long two-leg square cylinders. Upon light doping, find that ground system consistent mutually commensurate and power-law SC, charge (CDW) spin (SDW) correlations. The SC correlations are dominant between neighboring Cu sites d-wave pairing symmetry. Interestingly, near-neighbor interactions, especially attractive $V_{pd}$ interaction oxygen sites, can notably enhance while simultaneously suppressing CDW For modestly strong $V_{pd}$, become quasi-long-ranged susceptibility.

Language: Английский

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