Breakdown of the scaling relation of anomalous Hall effect in Kondo lattice ferromagnet USbTe

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Feb. 1, 2023

The interaction between strong correlation and Berry curvature is an open territory of in the field quantum materials. Here we report large anomalous Hall conductivity a Kondo lattice ferromagnet USbTe which dominated by intrinsic at low temperatures. However, induced effect does not follow scaling relation derived from Fermi liquid theory. onset contribution coincides with coherent temperature. Combined ARPES measurement DMFT calculations, this strongly indicates that hosted flat bands hybridization level. Our results demonstrate coherence has dramatic influence on temperature physical properties associated curvature, calling for new theories relations to account curvature.

Language: Английский

---

Two-Gap Superconductivity and the Decisive Role of Rare-Earth d Electrons in Infinite-Layer Nickelates

Physical Review Letters, Journal Year: 2024, Volume and Issue: 133(12)

Published: Sept. 17, 2024

We present a theoretical prediction of phonon-mediated two-gap superconductivity in infinite-layer nickelates Nd_{1-x}Sr_{x}NiO_{2} by performing ab initio GW and perturbation theory calculations. Electron self-energy effects significantly alter the characters two-band Fermi surface enhance electron-phonon coupling, compared with results based on density functional theory. Solutions fully k-dependent anisotropic Eliashberg equations yield two dominant s-wave superconducting gaps-a large gap band rare-earth Nd d interstitial orbital small transition-metal Ni character. Increasing hole doping induces non-rigid-band response electronic structure, leading to rapid drop T_{c} overdoped regime agreement experiments.

Language: Английский

---

Infinite-layer nickelates as Ni-eg Hund’s metals

npj Quantum Materials, Journal Year: 2023, Volume and Issue: 8(1)

Published: July 12, 2023

Abstract The recent and exciting discovery of superconductivity in the hole-doped infinite-layer nickelate Nd 1− δ Sr NiO 2 draws strong attention to correlated quantum materials. From a theoretical view point, this class unconventional superconducting materials provides an opportunity unveil physics hidden Here we study temperature doping dependence local spectrum as well charge, spin orbital susceptibilities from first principles. By using ab initio LQSGW+DMFT methodology, show that onsite Hund’s coupling Ni- d orbitals gives rise multiple signatures metallic phase e g orbitals. proposed picture nickelates (two orbital) metal differs Fe-based superconductors five cuprates doped charge transfer insulators. Our finding uncover new metals has potential implications for broad range two systems away half-filling.

Language: Английский

---

Crystallographic defects in Weyl semimetal LaAlGe

Physical Review Materials, Journal Year: 2024, Volume and Issue: 8(5)

Published: May 13, 2024

Crystallographic defects in a topological semimetal can result charge doping and scattering centers which may mask the exotic spectroscopic transport properties, respectively. Here, we investigate possible crystallographic including vacancy antisite Weyl LaAlGe using hybrid-density-functional theory calculations. We show that considerable concentration of Al- Ge-related naturally form during growth due to their low formation enthalpy. Specifically, Al be easily replaced by Ge $I{4}_{1}md$ phase LaAlGe, forming Ge-on-Al antisite, ${\mathrm{Ge}}_{\mathrm{Al}}$. The counterpart, Al-on-Ge (${\mathrm{Al}}_{\mathrm{Ge}}$), is also probable. most abundant defect ${\mathrm{Ge}}_{\mathrm{Al}}$ donorlike, effectively electron doping, these are therefore not only electronic process but induce substantial vertical shift chemical potential. results imply occurring hinder both features arising from physics LaAlGe. Our work applied $R\mathrm{AlGe}$ family ($R=\mathrm{rare}$ earth) help improve quality single-crystal magnetic semimetal.

Language: Английский

---

Dual nature of magnetism driven by momentum dependent f-d Kondo hybridization

Communications Physics, Journal Year: 2024, Volume and Issue: 7(1)

Published: June 12, 2024

Abstract The intricate nature of magnetism in uranium-based Kondo lattices is a consequence correlations between U-5 f and conduction electrons. Previously, the source has been ascribed to either Mott physics or Ruderman-Kittel-Kasuya-Yosida interaction, both which are not fully applicable lattices. Using linearized quasiparticle self-consistent GW plus dynamical mean-field theory, we demonstrate crossover from incoherent coherent - d cloud paramagnetic phase UTe 2 , USbTe USbSe. As transition occurs, observe an augmented coherence Pauli-like magnetic susceptibility, with substantial frozen moment persisting. We show that momentum dependent hybridization responsible for moments arising renormalized electrons’ van Hove singularity. Our findings provide perspective explain dual long-range ordering induced by pressure .

Language: Английский

---

Mott-Insulator State of FeSe as a Van der Waals 2D Material Is Unveiled

Physical Review Letters, Journal Year: 2024, Volume and Issue: 132(26)

Published: June 28, 2024

We undertook a comprehensive investigation of the electronic structure FeSe, known as Hund metal, and found that it is not uniquely defined. Through accounting for all two-particle irreducible diagrams constructed from electron Green's function G screened Coulomb interaction W in self-consistent manner, Mott-insulator phase 2D-FeSe unveiled. The metal-insulator transition driven by strong on-site its paramagnetic phase, accompanied weakening both local nonlocal screening effects on Fe-3d orbitals. Our results suggest Mott physics may play pivotal role shaping electronic, optical, superconducting properties monolayer or nanostructured FeSe.

Language: Английский

---

Absence of mixed valency for Pr in pristine and hole-doped PrNiO2

Physical review. B./Physical review. B, Journal Year: 2023, Volume and Issue: 107(16)

Published: April 27, 2023

Infinite-layer nickelates ($R$NiO$_2$) exhibit some distinct differences as compared to cuprate superconductors, leading a debate concerning the role of rare-earth ions ($R$=La, Pr, Nd) in low-energy many-body physics. Although $4f$ orbitals are typically treated inert `core' electrons studies, this approximation has been questioned. An active participation states is most likely for PrNiO$_2$ based on an analogy cuprates where Pr differ significantly from other cuprates. Here, we adopt density functional plus dynamical mean field theory (DFT+DMFT) investigate and more generally correlated electronic structure its hole-doped variant. We find that insulating show no evidence either Kondo resonance or Zhang-Rice singlet formation they do not have any hybridization channels near Fermi energy. The biggest effects hole doping shift $5d$ further away energy while enhancing Ni $3d$ - O $2p$ hybridization, thus reducing correlation get closer again physics upon doping. conclude by commenting implications reduced valence nickelates.

Language: Английский

---

Microscopic Magnetism of Nickel-Based Infinite-Layer Superconducting Parent Compounds RNiO₂ (R = La, Nd): A μSR Study

Chinese Physics Letters, Journal Year: 2024, Volume and Issue: 41(9), P. 097502 - 097502

Published: Aug. 8, 2024

Abstract By using muon spin relaxation (μSR) measurements, we perform a comparative study of the microscopic magnetism in parent compounds infinite-layer nickelate superconductors R NiO 2 ( = La, Nd). In either compound, zero-field μSR spectra down to lowest measured temperature reveal no long-range magnetic order. LaNiO , short-range correlations appear below T 150 K, and spins fully freeze ∼ 10 K. NdNiO exhibits more complex dynamics driven by Nd 4 f Ni 3 d electron fluctuations. Further, it shows features suggesting proximity spin-glass state occurring 5 both compounds, behavior with is further confirmed longitudinal-field measurements. These results provide new insight into superconducting nickelates, crucial understanding origin their superconductivity.

Language: Английский

---