Search arXiv⌕ Search

arXiv · cond-mat/9910373

High-resolution Ce 3d-edge resonant photoemission study of CeNi_2

Abstract

Resonant photoemission (RPES) at the Ce 3d -> 4f threshold has been performed for alpha-like compound CeNi_2 with extremely high energy resolution (full width at half maximum < 0.2 eV) to obtain bulk-sensitive 4f spectral weight. The on-resonance spectrum shows a sharp resolution-limited peak near the Fermi energy which can be assigned to the tail of the Kondo resonance. However, the spin-orbit side band around 0.3 eV binding energy corresponding to the f_{7/2} peak is washed out, in contrast to the RPES spectrum at the Ce 3d -> 4f RPES threshold. This is interpreted as due to the different surface sensitivity, and the bulk-sensitive Ce 3d -> 4f RPES spectra are found to be consistent with other electron spectroscopy and low energy properties for alpha-like Ce-transition metal compounds, thus resolves controversy on the interpretation of Ce compound photoemission. The 4f spectral weight over the whole valence band can also be fitted fairly well with the Gunnarsson-Schoenhammer calculation of the single impurity Anderson model, although the detailed features show some dependence on the hybridization band shape and (possibly) Ce 5d emissions.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

See-Hun Yang, S. -J. Oh, Hyeong-Do Kim, Ran-Ju Jung, A. Sekiyama, T. Iwasaki, S. Suga, Y. Saitoh, E. -J. Cho, J. -G. Park. 1999-10-23. High-resolution Ce 3d-edge resonant photoemission study of CeNi_2. https://doi.org/10.1103/physrevb.61.r13329

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Observable-Based Learning of Effective Entanglement Hamiltonians

Determining the entanglement Hamiltonian (EH) of an interacting quantum many-body system remains a fundamental challenge beyond special analytically tractable cases. Here we develop an observable-matching framework for learning effective EHs, which we demonstrate using response estimates from quantum Monte Carlo. As applications of this framework, we first calibrate the overall prefactor of the lattice Bisognano--Wichmann (LBW) construction using equal-time correlations and then learn spatially resolved couplings beyond its prescribed profile, without assuming a specific functional form for their spatial dependence. Trained solely on local correlations, the learned EHs reproduce benchmarked von Neumann and second Rényi entropies in $1$D and second Rényi entropies in $2$D. For a strong-bond cut associated with special surface criticality at the $(2+1)$D $O(3)$ Wilson--Fisher critical point, free-form learning outperforms the calibrated LBW ansatz in predicting the second Rényi entropy and reveals spatially nonuniform coupling renormalizations. Importantly, the learned EH also provides access to the von Neumann entropy in this setting, revealing a negative subleading correction and extending previous Rényi entropy findings to the von Neumann case. Directly evaluating the von Neumann entropy in such $(2+1)$D interacting quantum many-body systems remains challenging for conventional numerical methods. These results establish observable-based learning as a route to constructing effective entanglement Hamiltonians beyond prescribed spatial profiles in higher-dimensional interacting systems.

cond-mat.str-el↗

Extensions of the Haldane gap proof: higher dimensions, near degeneracy, fermions and tensor-network states

A recent remarkable paper by OpenAI showed that the spin-one Heisenberg chain with periodic boundary conditions has a spectral gap in the thermodynamic limit. The proof elegantly deduces this gap from the Hamiltonian's spectrum on a finite system. This basic idea is an inequality involving the purity of the original Gibbs state and a dual Gibbs state that is defined via space-time rotation. Here we consider a few generalizations of this purity bootstrap argument. We first extend it to arbitrary spatial dimensions. Our main result uses the space-time duality between symmetry generators and symmetry twists to obtain upper bounds on the splitting of nearly degenerate low-energy states, together with a nonzero gap above them, from finite-system information. As applications, we show that finite-system calculations for the 2+1-D toric code in a field and the 2+1-D transverse-field Ising model establish parameter regimes with four and two low-lying states whose splittings are bounded from above by $e^{-cL}$ and $e^{-cL^2}$ respectively for arbitrarily large system size $L$, while the gap above these states remains nonzero in the thermodynamic limit. Next, we extend it to fermionic systems and use a finite calculation to establish a symmetric mass generation phase in a $2+1$-D fermionic model. Finally, we apply the bootstrap to tensor-network states and establish exponential decay of connected correlations of all local operators in the symmetric square-lattice spin-one state introduced by Jian and Zaletel.

cond-mat.str-el↗

Interfacial polarity control of anomalous Hall effect in LaCoO3-SrIrO3 heterostructures

Interfacial polarity in oxide heterostructures can drive robust charge redistribution across the interface, yet its role in tailoring topological transport phenomena like the anomalous Hall effect (AHE) remains largely unexplored. Here, we control the sign of polarity-induced charge in SrIrO3-LaCoO3 interfaces by independently engineering the layer stacking sequence and the atomic termination. In-situ angle-resolved photoemission spectroscopy directly confirms the sign reversal of the induced charge in SrIrO3 through the contrasting electronic band shifts between different interfacial configurations. Magneto-transport measurements across a systematic matrix of four distinct heterostructures reveal that the AHE can be cleanly toggled on and off: it emerges exclusively under electron-doped conditions, while remaining suppressed for hole-doped SrIrO3. Our results establish that this response originates from an intrinsic, Berry-curvature-driven mechanism governed by polarity-controlled band filling of SrIrO3. These findings shift interfacial polarity from a passive structural consequence to an active design variable for engineering topological quantum states in oxide heterostructures.

cond-mat.str-el↗