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Beyond the conventional Emery model: crucial role of long-range hopping for cuprate superconductivity
Authors:
Eric Jacob,
M. O. Malcolms,
Viktor Christiansson,
Leonard M. Verhoff,
Paul Worm,
Liang Si,
Philipp Hansmann,
Thomas Schäfer,
Karsten Held
Abstract:
The Emery model is the quintessential model for cuprate superconductors. In his eponymous paper, Emery only considered the next-nearest-neighbor oxygen-copper hopping. Later, also the relevance of nearest- and next-nearest oxygen-oxygen hoppings has been pointed out. Using dynamical vertex approximation, we find a superconducting dome consistent with cuprates. However, long-range hoppings beyond t…
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The Emery model is the quintessential model for cuprate superconductors. In his eponymous paper, Emery only considered the next-nearest-neighbor oxygen-copper hopping. Later, also the relevance of nearest- and next-nearest oxygen-oxygen hoppings has been pointed out. Using dynamical vertex approximation, we find a superconducting dome consistent with cuprates. However, long-range hoppings beyond the three conventional hopping parameters are necessary for the quantitatively correct phase diagram and for a proper d-wave order parameter.
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Submitted 8 May, 2026;
originally announced May 2026.
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Rise and Fall of the Pseudogap in the Emery model: Insights for Cuprates
Authors:
M. O. Malcolms,
Henri Menke,
Yi-Ting Tseng,
Eric Jacob,
Karsten Held,
Philipp Hansmann,
Thomas Schäfer
Abstract:
The pseudogap in high-temperature superconducting cuprates is an exotic state of matter, displaying emerging Fermi arcs and a momentum-selective suppression of states upon cooling. We show how these phenomena are originating in the three-band Emery model by performing cutting-edge dynamical vertex approximation calculations for its normal state. For the hole-doped parent compound our results demon…
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The pseudogap in high-temperature superconducting cuprates is an exotic state of matter, displaying emerging Fermi arcs and a momentum-selective suppression of states upon cooling. We show how these phenomena are originating in the three-band Emery model by performing cutting-edge dynamical vertex approximation calculations for its normal state. For the hole-doped parent compound our results demonstrate the formation of a pseudogap due to short-ranged commensurate antiferromagnetic fluctuations. At larger doping values, progressively, incommensurate correlations and a metallic regime appear. Our results are in qualitative agreement with the normal state of cuprates, and, hence, represent a crucial step towards the uniform description of their phase diagrams within a single theoretical framework.
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Submitted 31 January, 2025; v1 submitted 19 December, 2024;
originally announced December 2024.
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Closing in on possible scenarios for infinite-layer nickelates: comparison of dynamical mean-field theory with angular-resolved photoemission spectroscopy
Authors:
Liang Si,
Eric Jacob,
Wenfeng Wu,
Andreas Hausoel,
Juraj Krsnik,
Paul Worm,
Simone Di Cataldo,
Oleg Janson,
Karsten Held
Abstract:
Conflicting theoretical scenarios for infinite-layer nickelate superconductors have been hotly debated, particularly regarding whether {only} a single Ni-3$d_{x^2-y^2}$ band is relevant at low energies besides electron pockets or whether multi-orbital physics including Ni-3$d_{z^2}$ is instead essential. The first scenario has emerged from density-functional theory plus dynamical mean-field theory…
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Conflicting theoretical scenarios for infinite-layer nickelate superconductors have been hotly debated, particularly regarding whether {only} a single Ni-3$d_{x^2-y^2}$ band is relevant at low energies besides electron pockets or whether multi-orbital physics including Ni-3$d_{z^2}$ is instead essential. The first scenario has emerged from density-functional theory plus dynamical mean-field theory (DFT+DMFT) calculations. Comparing the previous DFT+DMFT spectra to recent angular-resolved photoemission spectroscopy (ARPES) experiments, we find excellent agreement for both the Fermi surface and the strongly renormalized quasi-particle bands, supporting the first scenario. Our key findings further suggest that the "waterfalls" observed in ARPES might emerge from the quasi-particle--to--Hubbard-band crossover, and that additional spectral weight close to the $A$-pocket {likely} originates from the Ni-3$d_{xy}$ orbital.
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Submitted 24 November, 2024; v1 submitted 23 August, 2024;
originally announced August 2024.
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The Mesoscale Crystallinity of Nacreous Pearls
Authors:
Jiseok Gim,
Alden Koch,
Laura M. Otter,
Benjamin H. Savitzky,
Sveinung Erland,
Lara A. Estroff,
Dorrit E. Jacob,
Robert Hovden
Abstract:
A pearl's distinguished beauty and toughness are attributable to the periodic stacking of aragonite tablets known as nacre. Nacre has naturally occurring mesoscale periodicity that remarkably arises in the absence of discrete translational symmetry. Gleaning the inspiring biomineral design of a pearl requires quantifying its structural coherence and understanding the stochastic processes that infl…
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A pearl's distinguished beauty and toughness are attributable to the periodic stacking of aragonite tablets known as nacre. Nacre has naturally occurring mesoscale periodicity that remarkably arises in the absence of discrete translational symmetry. Gleaning the inspiring biomineral design of a pearl requires quantifying its structural coherence and understanding the stochastic processes that influence formation. By characterizing the entire structure of pearls (~3 mm) in cross-section at high resolution, we show nacre has medium-range mesoscale periodicity. Self-correcting growth mechanisms actively remedy disorder and topological defects of the tablets and act as a countervailing process to long-range disorder. Nacre has a correlation length of roughly 16 tablets (~5.5 um) despite persistent fluctuations and topological defects. For longer distances (> 25 tablets, ~8.5 um), the frequency spectrum of nacre tablets follows f^(-1.5) behavior suggesting growth is coupled to external stochastic processes-a universality found across disparate natural phenomena which now includes pearls.
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Submitted 22 October, 2021; v1 submitted 8 March, 2021;
originally announced March 2021.
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Nanoscale deformation mechanics reveal resilience in nacre of Pinna nobilis shell
Authors:
Jiseok Gim,
Noah Schnitzer,
Laura M. Otter,
Yuchi Cui,
Sébastien Motreuil,
Frédéric Marin,
Stephan E. Wolf,
Dorrit E. Jacob,
Amit Misra,
Robert Hovden
Abstract:
The combination of soft nanoscale organic components with inorganic nanograins hierarchically designed by natural organisms results in highly ductile structural materials that can withstand mechanical impact and exhibit high resilience on the macro- and nano-scale. Our investigation of nacre deformation reveals the underlying nanomechanics that govern the structural resilience and absorption of me…
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The combination of soft nanoscale organic components with inorganic nanograins hierarchically designed by natural organisms results in highly ductile structural materials that can withstand mechanical impact and exhibit high resilience on the macro- and nano-scale. Our investigation of nacre deformation reveals the underlying nanomechanics that govern the structural resilience and absorption of mechanical energy. Using high-resolution scanning/transmission electron microscopy (S/TEM) combined with in situ indentation, we observe nanoscale recovery of heavily deformed nacre that restores its mechanical strength on external stimuli up to 80% of its yield strength. Under compression, nacre undergoes deformation of nanograins and non-destructive locking across organic interfaces such that adjacent inorganic tablets structurally join. The locked tablets respond to strain as a continuous material, yet the organic boundaries between them still restrict crack propagation. Remarkably, the completely locked interface recovers its original morphology without any noticeable deformation after compressive contact stresses as large as 1.2 GPa.
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Submitted 24 October, 2019;
originally announced October 2019.