When localized spins on different d orbitals prefer different types of antiferromagnetic ordering, the Hund's rule coupling creates frustration. Using spin-wave theory we study the case of two such orbitals on a square lattice coupled through Hund's rule, such that the first one couples antiferromagnetically (AF) more strongly to its nearest neighbors, while the second couples more strongly to its next nearest neighbors. We find that the zero temperature phase diagram has four regions, one characterized by the familiar $(π,π)$ AF order, a second by the columnar $(π,0)$ order, a third by a {\it canted} order and a fourth region where a quantum-disordered state emerges. We comment on the possible relevance of these findings for the case of Fe-pnictide based antiferromagnets.
We investigate the one-dimensional ferromagnetic Kondo lattice in the hole-rich region. Of interest to us is the intermediate situation where the ferromagnetic Kondo coupling (Hund's coupling) is comparable to the electron bandwidth. The forced alignment favors triplet states whereas singlet states enter in a quite low-density regime. The direct antiferromagnetic exchange between the core spins is assumed to still prevail over the double exchange. We discuss a solvable limit showing that short-range antiferromagnetism in the spin array will affect the coherent propagation of triplets, i.e., tu…
The ground-state properties of CuFeAs were investigated by applying density functional theory calculations within generalized gradient approximation (GGA) and GGA+U. We find that the bicollinear antiferromagnetic state with antiparallel orbital magnetic moments on each iron which violates the Hund's rule is favored by the on-site Coulomb interaction, which is further stabilized by Cu vacancy. The magnetic ground state can be used to understand weak antiferromagnetism in CuFeAs observed experimentally. We argue that breakdown of the Hund's rule may be the possible origin for reduced magnetism i…
We show within the dynamical mean field theory that local multiplet interactions such as Hund's rule coupling produce local pairing superconductivity in the strongly correlated regime. Spin-triplet superconductivity driven by the Hund's rule coupling emerges from the pairing mediated by local fluctuations in pair exchange. In contrast to the conventional spin-triplet theories, the local orbital degrees of freedom has the anti-symmetric part of the exchange symmetry, leaving the spatial part as fully gapped and symmetric s-wave.
The multi-orbital Hubbard model in one dimension is studied using the numerical diagonalization method. Due to the effect of the crystal-field splitting $Δ$, the fully polarized ferromagnetism which is observed in the strong coupling regime becomes unstable against the partially polarized ferromagnetism when the Hund's rule coupling $J$ is smaller than a certain critical value of order of $Δ$. In the vicinity of the partially polarized ferromagnetism, the orbital fluctuation develops due to the competition between the Hund's rule coupling and the crystal-field splitting. The superconducting ph…
Motivated by the importance of antiferromagnetic skyrmions as building blocks of next-generation data storage and processing devices, we report theoretical and computational analysis of a model for a spin-orbit coupled correlated magnet on a triangular lattice. We find that two distinct antiferromagnetic skyrmion crystal (AF-SkX) states can be stabilized at low temperatures in the presence of external magnetic field. The results are obtained via Monte Carlo simulations on an effective magnetic model derived from the microscopic electronic Hamiltonian consisting of Rashba spin-orbit coupling, a…
The in-plane resistivity anisotropy has been studied with the Montgomery method on two detwinned parent compounds of the iron-based superconductors, NaFeAs and FeTe. For NaFeAs, the resistivity in the antiferromagnetic (AFM) direction is smaller than that in the ferromagnetic (FM) direction, similar to that observed in BaFe2As2 before. While for FeTe, the resistivity in the AFM direction is larger than that in the FM direction. We show that these two opposite resistivity anisotropy behaviors could be attributed to the strong Hund's rule coupling effects: while the iron pnictides are in the iti…
We present inelastic neutron scattering and magnetization measurements of the antiferromagnetic insulator LaMnPO that are well described by a Heisenberg spin model. These measurements are consistent with the presence of two-dimensional magnetic correlations up to a temperature T$_{max}$ $\approx$ 700 K >> T$_{N}$ = 375 K, the Néel temperature. Optical transmission measurements show the T = 300 K direct charge gap $Δ$ = 1 eV has decreased only marginally by 500 K and suggest it decreases by only 10% at T$_{max}$. Density functional theory and dynamical mean field theory calculations reproduce a…
An antiferromagnetic Hund coupling in multiorbital Hubbard systems induces orbital freezing and an associated superconducting instability, as well as unique composite orders in the case of an odd number of orbitals. While the rich phase diagram of the half-filled three-orbital model has recently been explored in detail, the properties of the doped system remain to be clarified. Here, we complement the previous studies by computing the entropy of the half-filled model, which exhibits an increase in the orbital-frozen region, and a suppression in the composite ordered phase. The doping dependent…
A new class of high temperature superconductors based on iron and arsenic was recently discovered, with superconducting transition temperature as high as 55 K. Here we show, using microscopic theory, that the normal state of the iron pnictides at high temperatures is highly anomalous, displaying a Curie Weiss susceptibility and a linear temperature dependence of the resistivity. Below a coherence scale T*, the resistivity sharply drops and susceptibility crosses over to Pauli-like temperature dependence. Remarkably, the coherence-incoherence crossover temperature is a very strong function of t…
We investigate a problem about the competition between the hybridization and the Hund-rule coupling by applying the Wilson numerical renormalization-group method to the extended Kondo model where the impurity spin interacts via the Hund-rule coupling, with an extra spin which is isolated from the conduction electrons. It is shown that the Hund-rule coupling is an irrelevant perturbation against the strong coupling fixed point. However, the Hund-rule coupling decreases the characteristic energy $T_K$ drastically to the lower side and the irrelevant operator, which describes the low energy physi…
We study the impact of Hund's-rule coupling on orbital excitations, as e.g. measured in inelastic resonant x-ray scattering. We find that the interpretation in terms of spin-orbit separation, which has been derived for one-dimensional systems without Hund's rule, remains robust in its presence. Depending on whether or not the orbital excitation includes a spin excitation, Hund's rule leads to an attractive or repulsive interaction between spinon and orbiton. Attraction and repulsion leave clear signatures through a transfer of spectral weight to the lower resp. upper edge of the spectrum.
Different models for doping of two-orbital chains with mobile $S=1/2$ fermions and strong, ferromagnetic (FM) Hund's rule couplings stabilizing the S=1 spins are investigated by density matrix renormalization group (DMRG) methods. The competition between antiferromagnetic (AF) and FM order leads to a rich phase diagram with a narrow FM region for weak AF couplings and strongly enhanced triplet pairing correlations. Without a level difference between the orbitals, the spin gap persists upon doping, whereas gapless spin excitations are generated by interactions among itinerant polarons in the pr…
We present a general model which includes the ferromagnetic Kondo lattice and the Hubbard model as special cases. The stability of the ferromagnetic state is investigated variationally. We discuss the mechanism of ferromagnetism in metallic nickel, emphasizing the importance of orbital degeneracy and the effect of the Hund's-rule coupling.
Antiferromagnetic resonance (AFMR) of BaCu2Si2O7 and a microscopic theory of the magnetic anisotropy of spin 1/2 chain compounds with folded CuO3 geometry being in good agreement with the available data are presented. The AFMR studies at 4.2 K show the existence of two gaps (40 and 76 GHz) at zero magnetic field and of two spin re-orientation transitions for H||c. The microscopic origin of the two gaps is shown to be Hund's rule coupling which leads to a "residual anisotropy" beyond the compensation of the Dzyaloshinskii-Moriya term by the symmetric anisotropy which would be valid without Hund…
The generalized spin-one-half Falicov-Kimball model with Hund and Hubbard coupling is used to examine effects of spin ordering on superconducting correlations in the strongly correlated electron and spin systems. It is found that the ferromagnetic spin clusters (lines, bands, domains) suppress the superconducting correlations in the d-wave chanel, while the antiferromagnetic ones have the fully opposite effect. The enhancement of the superconducting correlations due to the antiferromagnetic spin ordering is by factor 3 in the axial striped phase and even by the factor 8 in the phase segregated…
In most magnetically-ordered iron pnictides, the magnetic moments lie in the FeAs planes, parallel to the modulation direction of the spin stripes. However, recent experiments in hole-doped iron pnictides have observed a reorientation of the magnetic moments from in-plane to out-of-plane. Interestingly, this reorientation is accompanied by a change in the magnetic ground state from a stripe antiferromagnet to a tetragonal non-uniform magnetic configuration. Motivated by these recent observations, here we investigate the origin of the spin anisotropy in iron pnictides using an itinerant microsc…
We study the influence of the lattice structure, the Jahn-Teller effect and the Hund's rule coupling on a metal-insulator transition in AnC60 (A= K, Rb). The difference in lattice structure favors A3C60 (fcc) being a metal and A4C60 (bct) being an insulator, and the coupling to Hg Jahn-Teller phonons favors A4C60 being nonmagnetic. The coupling to Hg (Ag) phonons decreases (increases) the value Uc of the Coulomb integral at which the metal-insulator transition occurs. There is an important partial cancellation between the Jahn-Teller effect and the Hund's rule coupling.
We discuss microscopic aspects of odd-parity triplet pair in orbital degenerate systems. From the concept of off-diagonal long-range order, a pair state is unambiguously defined as the eigenstate with the maximum eigenvalue of pair correlation function. Performing this scheme by a numerical technique, we clarify that the odd-parity triplet pair occurs as an out-of-phase combination of local triplets induced by Hund's rule coupling for the lattice including two sites in the unit cell.
The importance of Hund's rule coupling for the stabilization of itinerant ferromagnetism is investigated within a two-band Hubbard model. The magnetic phase diagram is calculated by finite-temperature quantum Monte Carlo simulations within the dynamical mean-field theory. Ferromagnetism is found in a broad range of electron fillings whereas antiferromagnetism exists only near half filling. The possibility of orbital ordering at quarter filling is also analyzed.
We calculate the electronic properties of the $t$-$J$ model on a $C_{60}$ molecule using the density-matrix renormalization group and show that Hund's first rule is violated and that for an average of three added electron per molecule, an effective attraction (pair-binding) arises for intermediate values of $t/J$. Specifically, it is energetically favorable to put four electrons on one $C_{60}$ and two on a second rather than putting three on each. Our results show that a dominantly electronic mechanism of superconductivity is possible in doped $C_{60}$.
We analyze a microscopic origin of the Kondo effect-assisted orbital order in heavy-fermion materials. By studying the periodic two-orbital Anderson model with two local electrons, we show that frustration of Hund's rule coupling due to the Kondo effect leads to an incommensurate spiral orbital and magnetic order, which exists only inside the Kondo screened (heavy-electron) phase. This spiral state can be observed in neutron and resonant X-ray scattering measurements in ${\rm U}$- and ${\rm Pr}$-based heavy-fermion compounds, and realized in cold atomic gases, e.g. fermionic ${}^{173}{\rm Yb}$…
We study the orbital and spin configurations of up to six electrons or holes charged into self-assembled InAs/GaAs quantum dots via single-particle pseudopotential and many-particle configuration interaction method. We find that while the charging of {\it electrons} follows both Hund's rule and the Aufbau principle, the charging of {\it holes} follows a non-trivial charging pattern which violates both the Aufbau principle and Hund's rule, and is robust against the details of the quantum dot size. The predicted hole charging sequence offers a new interpretation of recent charging experiments.
We investigate the ground-state property and the excitation gap of a one-dimensional spin-orbital model with isotropic spin and anisotropic orbital exchange interactions, which represents the strong-coupling limit of a two-orbital Hubbard model including the Hund's rule coupling ($J$) at quarter filling, by using a density-matrix renormalization group method. At J=0, spin and orbital correlations coincide with each other with a peak at $q=π/2$, corresponding to the SU(4) singlet state. On the other hand, spin and orbital states change in a different way due to the Hund's rule coupling. With in…
Hund's multiplicity rule is investigated for the carbon atom using quantum Monte Carlo methods. Our calculations give an accurate account of electronic correlation and obey the virial theorem to high accuracy. This allows us to obtain accurate values for each of the energy terms and therefore to give a convincing explanation of the mechanism by which Hund's rule operates in carbon. We find that the energy gain in the triplet with respect to the singlet state is due to the greater electron-nucleus attraction in the higher spin state, in accordance with Hartree-Fock calculations and studies incl…
Competition of crystal field splitting and Hund's rule coupling in magnetic metal-insulator transitions of half-filled two-orbital Hubbard model is investigated by multi-orbital slave-boson mean field theory. We show that with the increase of Coulomb correlation, the system firstly transits from a paramagnetic (PM) metal to a {\it Néel} antiferromagnetic (AFM) Mott insulator, or a nonmagnetic orbital insulator, depending on the competition of crystal field splitting and the Hund's rule coupling. The different AFM Mott insulator, PM metal and orbital insulating phase are none, partially and ful…
We investigate the occurrence of Hund's rule magnetism in C60(n+-) molecular ions, by computing the ground-state spin for all charge states n from -3 to +5. The two competing interactions, electron-vibration (e-v, including Jahn Teller, favoring low spin) and electron-electron (e-e, including Hund-rule exchange, favoring high spin), are accounted for based on previously computed ab-initio coupling parameters. Treating the ion coordinates as classical, we first calculate and classify the static Jahn-Teller distorted states for all n, inclusive of both e-v and e-e effects. We then correct the ad…
Using relativistic first-principles calculations, we show that the chemical trend of Dzyaloshinskii-Moriya interaction (DMI) in 3d-5d ultrathin films follows Hund's first rule with a tendency similar to their magnetic moments in either the unsupported 3d monolayers or 3d-5d interfaces. We demonstrate that, besides the spin-orbit coupling (SOC) effect in inversion asymmetric noncollinear magnetic systems, the driving force is the 3d orbital occupation and their spin flip/mixing processes with the spin-orbit active 5d states control directly the sign and magnitude of the DMI. The magnetic chiral…
We consider the orbitally degenerate 3-band Hubbard model with on-site interactions which favor low spin and low orbital angular momentum using standard second order perturbation theory in the large Hubbard-U limit. At even integer filling this model is a Mott insulator with a non-degenerate ground state that allows for a simple description of particle-hole excitations as well as gapped spin and orbital modes. We find that the Mott gap is generally indirect and that the single particle spectrum at low doping reappears close to even filling but rescaled by a factor 2/3 or 1/3. The model capture…
We analyze the stability of excitonic ground states in the two-band Hubbard model with additional electron-phonon and Hund's rule couplings using a combination of mean-field and variational cluster approaches. We show that both the interband Coulomb interaction and the electron-phonon interaction will cooperatively stabilize a charge density wave (CDW) state which typifies an "excitonic" CDW if predominantly triggered by the effective interorbital electron-hole attraction or a "phononic" CDW if mostly caused by the coupling to the lattice degrees of freedom. By contrast, the Hund's rule coupli…
Hund's rule is one of the fundamentals of the correlation physics at the atomic level, determining the ground state multiplet of the electrons. It consists of three laws: (i) maximum $S$ (total spin), (ii) maximum $L$ (total orbital angular momentum) under the constraint of (i), and (iii) the total angular momentum $J$ is $|L-S|$ for electron number less than half, while $J=L+S$ for more than half due to the relativistic spin-orbit interaction (SOI). In real systems, the electrons hop between the atoms and gain the itinerancy, which is usually described by the band theory. The whole content of…
We study tight-binding models of itinerant electrons in two different bands, with effective on-site interactions expressing Coulomb repulsion and Hund's rule. We prove that, for sufficiently large on-site exchange anisotropy, all ground states show metallic ferromagnetism: They exhibit a macroscopic magnetization, a macroscopic fraction of the electrons is spatially delocalized, and there is no energy gap for kinetic excitations.
We study and solve the ground-state problem of a microscopic model for a family of orbitally degenerate quantum magnets. The orbital degrees of freedom are assumed to have directional character and are represented by static Potts-like variables. In the limit of vanishing Hund's coupling, the ground-state manifold of such a model is spanned by the hard-core dimer (spin singlet) coverings of the lattice. The extensive degeneracy of dimer coverings is lifted at a finite Hund's coupling through an order-out-of-disorder mechanism by virtual triplet excitations. The relevance of our results to sever…
In order to explore the effects of structural geometry on properties of correlated metals we investigate the magnetic properties of cubic (3C) and hexagonal (4H) BaRuO$_3$. While the 3C variant of BaRuO$_3$ is ferromagnetic below 60K, the 4H phase does not show any long-range magnetic order, however, there is experimental evidence of short-range antiferromagnetic correlations. Employing a combination of computational tools, namely density-functional theory and dynamical mean-field theory calculations, we probe the origin of contrasting magnetic properties of BaRuO$_3$ in the 3C and 4H structur…
Studies of the effects of the Hund's rule coupling J_H in multiple orbit impurities or quantum dots using different models have led to quite different predictions for the Kondo temperature T_K as a function of J_H. We show that the differences depend on whether or not the models conserve orbital angular momentum about the impurity site. Using numerical renormalization group (NRG) calculations, we deduce the renormalized parameters for the Fermi liquid regime, and show that, despite the differences between the models, the low energy fixed point in the strong correlation regime is universal with…
We investigate the ground-state property of a one-dimensional two-orbital Hubbard model at quarter filling by numerical techniques such as the density-matrix renormalization group method and the exact diagonalization. When the Hund's rule coupling $J$ is zero, the model is SU(4) symmetric. In fact, both spin and orbital correlations have a peak at $q=π/2$, indicating an SU(4) singlet state with a four-site periodicity. On the other hand, with increasing $J$, it is found that the peak position of the orbital correlation changes to $q=π$, while that of the spin correlation remains at $q=π/2$. We…
Multiorbital interactions have the capacity to produce an interesting kind of doublon-holon bound state that consists of a single-hole state in one band and a doubly-occupied state in another band. Interband doublon-holon pair excitations in the two-orbital Hubbard model are studied by using dynamical mean-field theory with the Lanczos method as the impurity solver. We find that the interband bound states may provide several in-gap quasiparticle peaks in the density of states of the narrow band in the orbital-selective Mott phase with a small Hund's rule coupling ($J$). There exists a correspo…
We study non-equilibrium current fluctuations through a quantum dot, which includes a ferromagnetic Hund's rule coupling $J$, in the low-energy Fermi liquid regime using the renormalized perturbation theory. The resulting cumulant for the current distribution in the particle-hole symmetric case, shows that spin-triplet and spin-singlet pairs of quasiparticles are formed in the current due to the Hund's rule coupling and these pairs enhance the current fluctuations. In the fully screened higher-spin Kondo limit, the Fano factor takes a value $F_b = (9M+6)/ (5M+4)$ determined by the orbital dege…
We extend the renormalized perturbation theory for the single impurity Anderson model to the n-channel model with a Hund's rule coupling, and show that the exact results for the spin, orbital and charge susceptibilities, as well as the leading low temperature dependence for the resistivity, are obtained by working to second order in the renormalized couplings. A universal relation is obtained between the renormalized parameters, independent of n, in the Kondo regime. An expression for the dynamic spin susceptibility is also derived by taking into account repeated quasiparticle scattering, whic…
A comparative density functional plus dynamical mean field theory study of the pseudocubic ruthenate materials CaRuO$_3$ and SrRuO$_3$ is presented. Phase diagrams are determined for both materials as a function of Hubbard repulsion $U$ and Hund's rule coupling $J$. Metallic and insulating phases are found, as are ferromagnetic and paramagnetic states. The locations of the relevant phase boundaries are determined. Based on the computed phase diagrams, Mott-dominated and Hund's dominated regimes of strong correlation are distinguished. Comparison of calculated properties to experiments indicate…
We discuss a mechanism of real-space spin-triplet pairing, alternative to that due to quantum paramagnon excitations, and demonstrate its applicability to $\mathrm{UGe_2}$. Both the Hund's rule ferromagnetic exchange and inter-electronic correlations contribute to the same extent to the equal-spin pairing, particularly in the regime in which the weak-coupling solution does not provide any. The theoretical results, obtained within the orbitally-degenerate Anderson lattice model, match excellently the observed phase diagram for $\mathrm{UGe_2}$ with the coexistent ferromagnetic (FM1) and superco…
We explore the predictions of the renormalized perturbation theory for an n-channel Anderson model, both with and without Hund's rule coupling, in the regime away from particle-hole symmetry. For the model with n=2 we deduce the renormalized parameters from numerical renormalization group calculations, and plot them as a function of the occupation at the impurity site, nd. From these we deduce the spin, orbital and charge susceptibilities, Wilson ratios and quasiparticle density of states at T=0, in the different parameter regimes, which gives a comprehensive overview of the low energy behavio…
We study the finite-temperature properties of the half-filled two-band Hubbard model in the presence of Hund's rule coupling and orbital anisotropy. We use the mean-field treatment of the $Z_2$ slave-spin theory with a finite-temperature extension of the zero-temperature gauge variable previously developed by Hassan and de' Medici http://dx.doi.org/10.1103/PhysRevB.81.035106}{Phys. Rev. B {\bf 81}, 035106 (2010)}]. We consider the instability of the Fermi liquid phases and how it is enhanced by the Hund's rule. We identify paramagnetic solutions that have zero quasi-particle weight with bad me…
We investigate the phase diagram of the spin-orbit-coupled three orbital Hubbard model at arbitrary filling by means of dynamical mean-field theory combined with continuous-time quantum Monte Carlo. We find that the spin-freezing crossover occurring in the metallic phase of the non-relativistic multiorbital Hubbard model can be generalized to a $\mathbf{J}$-freezing crossover, with $\mathbf{J}=\mathbf{L}+\mathbf{S}$, in the spin-orbit-coupled case. In the $\mathbf{J}$-frozen regime the correlated electrons exhibit a non-trivial flavor selectivity and energy dependence. Furthermore, in the regi…
We show that in multi-band metals the correlations are strongly affected by the Hund's rule coupling, which depending on the filling promotes metallic, insulating or bad-metallic behavior. The quasiparticle coherence and the proximity to a Mott insulator are influenced distinctly and, away from single- and half-filling, in opposite ways. A strongly correlated bad-metal far from a Mott phase is found there. We propose a concise classification of 3d and 4d transition-metal oxides within which the ubiquitous occurrence of strong correlations in Ru- and Cr-based oxides, as well as the recently mea…
By reverse-engineering from exact solutions we obtain Hartree-exchange-correlation (Hxc) potentials for a double quantum dot subject to generic density-density interactions and Hund's rule coupling. We find ubiquitous step structures of the Hxc potentials that can be understood and derived from an analysis of stability diagrams. We further show that a generic Hxc potential can be decomposed into four basic potentials which allows for a straight-forward parametrization and paves the road for the construction of Hxc potentials for interacting multi-orbital systems. Finally we employ our parametr…
We investigate the Cu $L_3$ edge resonant inelastic x-ray scattering (RIXS) spectra of a quasi-1D antiferromagnet Ca$_2$CuO$_3$. In addition to the magnetic excitations, which are well-described by the two-spinon continuum, we observe two dispersive orbital excitations, the $3d_{xy}$ and the $3d_{yz}$ orbitons. We carry out a quantitative comparison of the RIXS spectra, obtained with two distinct incident polarizations, with a theoretical model. We show that any realistic spin-orbital model needs to include a finite, but realistic, Hund's exchange $J_H \approx 0.5$ eV. Its main effect is an in…
The N=0 Landau levels of ABC and ABA trilayer graphene both have approximate 12-fold degeneracies that are lifted by interactions to produce strong quantum Hall effects (QHE) at all integer filling factors between nu=-6 and nu=6. We discuss similarities and differences between the strong-magnetic-field weak-disorder physics of the two trilayer cases, and between trilayer and bilayer cases. These differences can be used to identify the stacking order of high-quality trilayer samples by studying their quantum Hall effects.
The extent to which quantum criticality drives the physics of iron pnictides is a central question in the field. Earlier theoretical considerations were based on an effective field theory, and the proposed realization in P-doped iron arsenides has received extensive experimental evidence. To connect the quantum critical behavior with the underlying electronic physics, it is important to analyze it within microscopic models. Here, we do so for a multi-orbital model containing both Hubbard and Hund's interactions, by a variational Monte Carlo method based on Jastrow-Slater wave functions that al…
We study numerically the one-dimensional Kondo and Hund lattices consisting of localized spins interacting antiferro or ferromagnetically with the itinerant electrons, respectively. Using the Density Matrix Renormalization Group we find, for both models and in the small coupling regime, the existence of new magnetic phases where the local spins order forming ferromagnetic islands coupled antiferromagnetically. Furthermore, by increasing the interaction parameter $|J|$ we find that this order evolves toward the ferromagnetic regime through a spiral-like phase with longer characteristic wave len…
Uranium compounds can manifest a wide range of fascinating many-body phenomena, and are often thought to be poised at a crossover between localized and itinerant regimes for 5f electrons. The antiferromagnetic dipnictide USb2 has been of recent interest due to the discovery of rich proximate phase diagrams and unusual quantum coherence phenomena. Here, linear-dichroic X-ray absorption and elastic neutron scattering are used to characterize electronic symmetries on uranium in USb2 and isostructural UBi2. Of these two materials, only USb2 is found to enable strong Hund's rule alignment of local …
