Frustrated superconductivity and intrinsic reduction of <i>T</i>_<i>c</i> in trilayer nickelate

The Innovation Materials, Journal Year: 2024, Volume and Issue: 2(4), P. 100102 - 100102

Published: Jan. 1, 2024

<p>Identifying the key factors controlling magnitude of <i>T</i>_<i>c</i> is critical importance in pursuit high-temperature superconductivity. In cuprates, reaches its maximal value trilayer structure, leading to belief that interlayer coupling may help promote pairing. contrast, for recently discovered nickelate superconductors under high pressure, maximum reduced from about 80 K bilayer La₃Ni₂O₇ 30 La₄Ni₃O₁₀. Motivated by this opposite trend, we propose an pairing scenario superconductivity Our theory reveals intrinsic frustration spin-singlet inner layer tends form with both two outer layers respectively, strong superconducting fluctuations between layers. This explains reduction compared La₃Ni₂O₇. findings support a fundamental distinction multilayer and cuprate superconductors, ascribe it their different (interlayer versus intralayer) mechanisms. Furthermore, our predicts extended <i>s</i>^<i>±</i>-wave gap structures La₄Ni₃O₁₀, varying signs possible nodes on Fermi pockets. We also find Josephson potentially interesting consequences be examined future experiments. work possibility rich novel physics pairing.</p>

Language: Английский

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Pressure‐Dependent “Insulator–Metal–Insulator” Behavior in Sr‐Doped La₃Ni₂O₇

Advanced Electronic Materials, Journal Year: 2024, Volume and Issue: 10(9)

Published: May 1, 2024

Abstract Recently, superconductivity at high temperatures is observed in bulk La 3 Ni 2 O 7−δ under pressure. However, the attainment of high‐purity single crystals remains a formidable challenge. Here, crystal structure and physical properties Sr‐doped 7 synthesized pressure (20 GPa) temperature (1400 °C) are reported. Through X‐ray diffraction, it shown that high‐pressure‐synthesized paramagnetic crystallizes an orthorhombic with Ni─O─Ni bond angles 173.4(2)° out‐of‐plane 175.0(2)°and 176.7(2)°in plane. The substitution Sr alters band filling ratio 2+ /Ni 3+ , aligning them those “La 7.05” thereby leading to significant modifications relative unsubstituted parent phase. At ambient pressure, exhibits insulating properties, conductivity increases as goes up 10 GPa. upon further increasing beyond 10.7 GPa, transits back from metal‐like behavior insulator. insulator–metal–insulator trend dramatically differs compound despite their similar low‐pressure regime. These experimental results underscore considerable challenge achieving nickelates.

Language: Английский

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Distinct ultrafast dynamics of bilayer and trilayer nickelate superconductors regarding the density-wave-like transitions

Science Bulletin, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 1, 2024

Language: Английский

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s± -wave superconductivity in pressurized La4Ni3O10

Physical review. B./Physical review. B, Journal Year: 2024, Volume and Issue: 110(18)

Published: Nov. 4, 2024

Recently, evidence of superconductivity (SC) has been reported in pressurized ${\mathrm{La}}_{4}{\mathrm{Ni}}_{3}{\mathrm{O}}_{10}$. Here we study its possible pairing mechanism and symmetry. Through fitting the density-functional-theory band structure, provide a six-orbital tight-binding model. In comparison with structure ${\mathrm{La}}_{3}{\mathrm{Ni}}_{2}{\mathrm{O}}_{7}$, additional nonbonding ${d}_{{z}^{2}}$ is important to here. When multiorbital Hubbard interactions are included, our random-phase-approximation based yields an ${s}^{\ifmmode\pm\else\textpm\fi{}}$-wave SC. The dominant Fermi-surface nesting vector ${\mathbf{Q}}_{1}\ensuremath{\approx}(\ensuremath{\pi},\ensuremath{\pi})$ between $\ensuremath{\gamma}$ pocket contributed by bonding top ${\ensuremath{\alpha}}_{1}$ bottom, leading strongest amplitude opposite gap signs within two regimes. real-space interlayer ${d}_{{z}^{2}}$-orbital pairing. This pattern insensitive details. Upon electron doping, ${T}_{c}$ would increase promptly before system enters N\'eel-ordered spin-density-wave phase.

Language: Английский

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Temperature-Dependent Structural Evolution of Ruddlesden–Popper Bilayer Nickelate La₃Ni₂O₇

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 10, 2025

A recent article ( J. Am. Chem. Soc. 2024, 146, 7506–7514) details a pressure–temperature (P–T) phase diagram for the Ruddlesden–Popper bilayer nickelate La3Ni2O7 (LNO-2222) using synchrotron X-ray diffraction. This study identifies transition from Amam (#63) to Fmmm (#69) within temperature range of 104–120 K under initial pressure and attributes I4/mmm (#139) space group structure responsible superconductivity LNO-2222. Herein, we examine temperature-dependent structural evolution LNO-2222 single crystals at ambient pressure. Contrary symmetry increase established Amam–Fmmm boundary, observe an enhancement in reflections as decreases. work not only delivers high-quality crystallographic data laboratory X-rays across various temperatures but also enhances understanding complex behavior this system, contributing insights further experimental theoretical explorations.

Language: Английский

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