Latest Publications - Computational Quantum Materials

Twisted Bilayer Graphene Lifetimes At Integer Fillings: An Analytic Result. Hu, Haoyu; Shao, Yuelin; Crippa, Lorenzo; Călugăru, Dumitru; Sangiovanni, Giorgio; Wehling, Tim; Glazman, Leonid I.; Bernevig, B. Andrei. In arXiv:2604.14303v1. 2026.

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Twisted bilayer graphene near integer fillings hosts correlated single-particle excitations whose dispersion and linewidth are increasingly accessible experimentally. We study these excitations using the topological heavy-fermion model, which captures both strong correlations and band topology of twisted bilayer graphene. In the decoupled limit, where both the single-particle fc hybridization and the Hund coupling between f and c electrons are absent, the model admits exact solutions in which free Dirac fermions coexist with interacting f electrons that form zero-width Hubbard bands. By treating the fc hybridization and Hund coupling perturbatively around this solvable limit, we obtain analytical results for the single-particle self-energy. From the resulting self-energy, we derive explicit expressions for both dispersion renormalization and scattering rates of both Hubbard-band excitations and low-energy Dirac modes, thereby establishing an analytical framework for understanding correlated excitations in twisted bilayer graphene. We analyze the scattering of the two kinds, Gamma3 and Gamma1,2, of Dirac electrons and find that they arise from different mechanisms. We also briefly investigate the effect of strain. Finally, we compare these analytical expressions with DMFT results for the same model.

Anomalous thermopower from the drag of overdamped collective modes. Mirarchi, G.; Seibold, G.; Grilli, M.; Caprara, S. In arXiv:2607.02449v1. 2026.

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Inspired by the observation of a Seebeck coefficient ratio that exhibits a seemingly logarithmic divergence at low temperature in high-temperature superconducting cuprates, we show that a mechanisms similar to the standard phonon drag can give rise to anomalies in the thermopower of a metal, if the dragged collective mode is overdamped, with a damping coefficient that increases with lowering the temperature. Our finding adds a piece to the puzzle of the strange-metal behavior observed in many different systems and supports our proposal that overdamped charge density fluctuations can be responsible of such a behavior in high-temperature superconducting cuprates.

Distinct lattice and charge excitations in AV3Sb5 kagome superconductors. Oh, Dongjin; Enzner, Stefan; Klebl, Lennart; Scammell, Harley D.; Ingham, Julian; Wehling, Tim; Sangiovanni, Giorgio; Thomale, Ronny; Demir, Ahmet Kemal; Occhialini, Connor; Wulferding, Dirk; Wang, Ziqiang; Salinas, Andrea C.; Wilson, Stephen D.; Comin, Riccardo. In arXiv:2605.20573v1. 2026.

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The kagome superconductor family AV3Sb5 (A=Cs, Rb, K) provides a rich platform for exploring diverse electronic symmetry breaking phenomena, including superconductivity and various forms of density wave orders. Although these compounds share the identical lattice structure in the normal state, they exhibit distinct forms of symmetry breaking upon entering the charge density wave (CDW) phase, and the microscopic origin of which remain elusive. Here, we investigate the lattice and charge degrees of freedom in AV3Sb5 using angle-resolved polarized Raman spectroscopy. Our comprehensive polarization-resolved measurements reveal that the lifting of the twofold-degeneracy of the E2g phonon mode in the CDW phase-previously reported only in CsV3Sb5 with a 3 GHz splitting-also appears ubiquitously in the other two compounds. In contrast, the collective CDW excitations exhibit markedly different polarization dependences depending on the alkali-metal species. These distinct behaviors in the lattice and charge channels provide crucial insight into the enigmatic material-dependent symmetry breaking phenomena that appear in the CDW phase. Furthermore, our experiments, together with first-principles calculations and an effective Hamiltonian model, shed light on the nature of the charge order structure in AV3Sb5 kagome superconductors.

First-principles calculation of coherence length and penetration depth based on density functional theory for superconductors. Kawamura, Mitsuaki; Nomoto, Takuya; Witt, Niklas; Arita, Ryotaro. In arXiv:2603.05123v2. 2026.

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We develop a first-principles framework for evaluating the fundamental length scales of superconductivity, namely the coherence length \($ξ_0$\) and the magnetic penetration depth \($λ_\mathrmL$\), within superconducting density functional theory (SCDFT). By incorporating finite-momentum Cooper pairs, we formulate a microscopic scheme that enables a consistent and parameter-free determination of \($ξ_0$\), \($λ_\mathrmL$\), and the superconducting transition temperature \($T_\mathrmc$\) on the same theoretical footing. Applying the method to representative elemental superconductors, the A15 compound V\($_3$\)Si, and H\($_3$\)S under high pressure, we obtain results in good agreement with available experimental and reproduce the type-I/type-II classification across all materials studied. The unified access to \($ξ_0$\) and \($λ_\mathrmL$\) further allows us to construct the Uemura plot entirely from first principles, showing that higher-\($T_\mathrmc$\) systems are characterized by the simultaneous realization of strong pairing and large phase stiffness. Our results establish a predictive first-principles route to superconducting length scales and provide a microscopic interpretation of empirical correlations in superconductivity.

Poles-zeros duality in semi-holographic Mott insulators. Kögel, Thomas; Caddeo, Alessio; Pitters, Amelie; Paoletti, Francesca; Crippa, Lorenzo; Sangiovanni, Giorgio; Meyer, René; Erdmenger, Johanna. In arXiv:2605.20321v2. 2026.

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Inspired by the poles-zeros duality of Green's functions that appears in transitions into Mott-insulating phases in strongly correlated condensed matter systems, we propose a semi-holographic approach to Mott insulators. In this model, a fundamental fermion is coupled to a large-\($N$\), strongly interacting sector that generates a self-energy for the fundamental fermion's Green's function. This coupling amounts to a hybridization of the fundamental fermion with a strongly correlated fermionic composite. Within the holographic framework, at large \($N$\), the Green's function of the composite fermion naturally exhibits a poles-zeros duality. Zeros of the Green's function are caused by the poles of the self-energy that correspond to collective many-body excitations of the holographic strongly interacting sector. We calculate the spectral function of the fundamental fermion, from which we characterize the semi-holographic metallic and the Mott-insulating phases. In addition to the new physical interpretation of the zeros, our analysis yields a well-defined picture of the poles-zeros duality in terms of the freedom to choose between standard and alternative quantization in the strongly coupled sector.

Tuning the Charge Transfer of Transition Metal Dichalcogenides via Misfit Layer Compounds. Du, Hugo Le; Zullo, Ludovica; Cordiez, Justine; Salvatore, Robin; Marini, Giovanni; Hervé, Marie; Pierucci, Debora; Sasaki, Shunsuke; Pawula, Florent; Janod, Etienne; Bigi, Chiara; Zonno, Marta; Bertran, François; Jaouen, Thomas; Fèvre, Patrick Le; Calandra, Matteo; Cario, Laurent; Cren, Tristan; Angelo, Marie D. In arXiv:2605.18317v1. 2026.

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Misfit layer compounds (MLCs) are a versatile platform for exploring the electronic phase diagram of two dimensional (2D) materials beyond the limits of conventional gating techniques. This work demonstrates the precise tunability of electron doping in NbSe2 monolayers through chemical alloying within the rocksalt layer of (LaxPb1xSe)1.14(NbSe2)2 heterostructures. By combining first principles density functional theory (DFT) calculations with angle resolved photoemission spectroscopy (ARPES), we prove that the rocksalt unit acts as an universal electron donor. We show that varying the La Pb ratio results in a rigid Fermi level shift, still preserving the NbSe2 electronic structure. Crucially, photon energy dependent ARPES confirms that the NbSe2 layers nearly maintain their intrinsic 2D character and orbital identity within the three dimensional misfit. This study establishes MLCs as a reliable platform for engineering emergent states in 2D transition metal dichalcogenides through precise stoichiometric control.

Altermagnons at the metal-insulator transition. Issing, Jonas; Dürrnagel, Matteo; Mazumdar, Sarbajit; Lorenz, Alena; Witt, Niklas; Sangiovanni, Giorgio; Klett, Michael; Klebl, Lennart; Thomale, Ronny; Seufert, Jannis. In arXiv:2605.11669v1. 2026.

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By means of slave-boson theory for the Hubbard model on the checkerboard lattice, we calculate dynamical altermagnetic spin susceptibilities from the metallic to the Mott-insulating regime. We track magnon dispersion and lifetime renormalization, allowing us to uncover a crossover from a chirality-selective dissipation of magnon modes to coherent yet strongly deformed chiral magnon branches across the metal insulator transition. Our formalism lends itself to a quantitative description of collective spin dynamics in correlated altermagnets.

Nonlinear Hall Effect in Metal-Organic Frameworks. Mazumdar, Sarbajit; S, Jagadish N; Narayan, Awadhesh; Sangiovanni, Giorgio; Thomale, Ronny; Bandyopadhyay, Arka. In arXiv:2603.09612v2. 2026.

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We propose metal-organic frameworks (MOFs) as tunable platforms for nonlinear Hall responses. A universal analytical downfolding scheme maps \($C_3$\)-symmetric frameworks onto star- and honeycomb-lattice models, reproducing first-principles Dirac features. Spin-orbit coupling and broken inversion symmetry gap the Dirac cones, generating Berry-curvature hot spots. Symmetry analysis identifies tailored synthetic pathways, including linker design, as intrinsic routes to engineer nonlinear Hall transport beyond strain and substrate control.

Enhanced Screening in Epitaxial Graphene via Nearly Free-Electron Metal Intercalation. Schmitt, Cedric; Gehrig, Lukas; Erhardt, Jonas; Strauß, Kilian; Enzner, Stefan; Kamp, Martin; Kim, Timur; Sangiovanni, Giorgio; Schäfer, Jörg; Moser, Simon; Claessen, Ralph. In arXiv:2608.10580v1. 2026.

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Graphene exhibits extraordinarily high carrier mobility, making it a promising platform for next-generation electronics. Scalable growth on SiC, however, suffers from limited dielectric screening at the graphene-substrate interface, degrading electronic performance. In this work, we systematically enhance dielectric screening by intercalating a bilayer of indium at the graphene-SiC interface. Using graphene's plasmaronic signature observed in angle-resolved photoemission spectroscopy as a proxy for interaction strength, we quantitatively demonstrate strong dielectric screening arising from the interplay of both indium layers. Layer-resolved density functional theory shows that the first indium layer acts as a buffer that absorbs substrate interactions, enabling the second layer to form a nearly free-electron system that efficiently screens the graphene layer above. Experiments with only a single intercalated indium layer reveal reduced screening, confirming the essential role of the second layer. Our results establish 2ML indium intercalation as a powerful route for engineering dielectric environments in graphene.

Resonantly-enhanced Raman response in graphene-capped bismuthene on SiC. Gehrig, Lukas; Schmitt, Cedric; Fragomeni, Erica; Sotgiu, Simone; Enzner, Stefan; Venanzi, Tommaso; Liu, Bing; Strauß, Kilian; Erhardt, Jonas; Kamp, Martin; Stellino, Elena; Postorino, Paolo; Schäfer, Jörg; Moser, Simon; Stampfer, Christoph; Sangiovanni, Giorgio; Claessen, Ralph; Baldassarre, Leonetta. In arXiv:2608.01961v1. 2026.

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Two-dimensional quantum spin Hall insulators based on atomic monolayers offer a promising route toward dissipationless electronics, yet their practical use is often limited by environmental instability. Encapsulating the system with a graphene capping layer has been shown to be a reliable method to prevent oxidation and degradation. However, the confirmation of a successful encapsulation still relies on ultra-high vacuum techniques, that considerably slow the process. Here, we present an ex situ, rapid, nondestructive and spatially resolved Raman characterization of graphene-capped bismuthene, a honeycomb monolayer of Bi on SiC. A pronounced Raman scattering peak at around 122 cm-1 is identified as the E2g phonon of bismuthene, via a comparison with density functional perturbation theory calculations. We use excitation-energy and polarization-dependent Raman measurements to enable an unambiguous assignment of the spectral features. Tuning the excitation energy close to the excitonic transition in pristine bismuthene, we observe a strong enhancement of the Raman response and the emergence of additional scattering peaks. In this regime, higher-order phonon features, as well as interfacial modes between bismuthene and the SiC substrate, become visible, suggesting the involvement of resonant scattering processes. Our results establish Raman micro-spectroscopy as a versatile tool for probing graphene-protected quantum materials, providing access to lattice dynamics and interlayer coupling.

Heterostructuring as Gateway to Electron Doping of Nickelate Superconductors. Deng, Chao; Kitatani, Motoharu; Jiang, Guiwen; Guo, Siqi; Witt, Niklas; Zhang, Ao; Wu, Wenfeng; Jiang, Mi; Held, Karsten; Si, Liang. In arXiv:2607.08553v1. 2026.

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Despite enormous expenditures in the research field, the electron-doped side of nickelate superconductors remains uncharted territory. Substituting the trivalent rare-earth cations by a tetravalent one hitherto failed. Here, we demonstrate by first-principles calculations a disorder-free route to electron dope Ruddlesden-Popper nickelates. When intercalating wide-band-gap insulating layers such as La\($X$\)O\($_3$\) (\($X$\)=Al, Ga, Sc) into La\($_2$\)NiO\($_4$\), the extra (LaO)\($^+$\) layers act as electron donors, releasing carriers into the Ni-3\($d$\) orbitals. This electron doping puts La\($_2$\)NiO\($_4$\):La\($_2$\)AlO\($_4$\) naturally in the optimal region for \($d_x^2-y^2$\)-wave superconductivity with T\($_c$\) exceeding 50 K. The same concept also allows us to electron dope La\($_3$\)Ni\($_2$\)O\($_7$\), the superconductor in the limelight.

The charge density fluctuations and the Shrinking Fermi Liquid scenario for strange metallicity in cuprates. Caprara, Sergio; Bhattacharyya, Sauri; Castro, Carlo Di; Mirarchi, Giovanni; Seibold, Götz; Grilli, Marco. In arXiv:2607.08476v1. 2026.

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We interpret the strange metal (SM) properties of slightly overdoped cuprates in terms of the recently proposed Shrinking Fermi Liquid theory. This is based on the pervading presence in the cuprate phase diagram of charge density fluctuations (CDF), which have been identified and characterized in RIXS. These fluctuations are abundant and have a low energy due to the proximity of the charge density wave quantum critical point hidden under the superconducting dome of cuprates, but have a short range and non-critical character with a finite energy M/γ~10 meV as measured above Tc. Here M~ ξ^-2 is determined by the short correlation length ξ, while γencodes the Landau damping ruling the lifetime of the charge fluctuations. Besides these low energy CDF, cuprates also display phonons and a broad continuum of particle-hole excitations, mostly due to spin paramagnons arising from their strongly correlated character. With these experimentally characterized ingredients we show that above Tc the SM properties in transport are well described in terms of fermionic Landau quasiparticles scattering with CDF and phonons. The optical properties can instead be interpreted by the combined effect of low energy CDF determining the temperature dependence, and of the paramagnon continuum determining a linear in frequency scattering rate. Remarkably, the combined effect of these simple ingredients also induces ω/T scaling properties for frequencies larger than M/γ. When superconductivity is suppressed by strong magnetic fields the SM properties extend down to a few Kelvin. By assuming that the CDF dissipation parameter γgrows logarithmically by lowering T, we account for all anomalous transport and thermodynamic properties of cuprates (specific heat, Seebeck, heat transport, resistivity, and magnetoresistance) thereby providing a consistent scenario for the SM phase of cuprates.

Doping tunable charge density waves in misfit layer compounds. Du, Hugo Le; Zullo, Ludovica; Cordiez, Justine; Salvatore, Robin; Schmieg, Daniel; Mukherjee, Arindam; Marini, Giovanni; Volavka, Dominik; Debontridder, Francois; Herve, Marie; Samuely, Tomas; Sasaki, Shunsuke; Pawula, Florent; Janod, Etienne; Calandra, Matteo; Cario, Laurent; Cren, Tristan. In arXiv:2607.19095v1. 2026.

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The ability to tune charge density waves (CDWs) through external control knobs, such as doping, pressure or strain is crucial for exploring the phase diagram of two dimensional (2D) or quasi-2D materials. Yet, controlling CDWs critical temperature and ordering vector remains a challenge for current experimental techniques. In this work, we establish misfit layer compound heterostructures as a reliable platform to manipulate CDWs in transition metal dichalcogenides. By combining ab initio calculations with low-temperature scanning tunneling microscopy, we show how to achieve doping tunable control over NbSe2 CDW by chemically alloying in the rocksalt subunit. Crucially, we prove that tuning the La Pb ratio in the misfit family (LaxPb1xSe)1.14(NbSe2)2 enables stabilization of different CDW orders, such as 2x2 or 3x3 patterns, and even coexisting phases. This work paves the way for engineering transition metal dichalcogenides with tailored charge density waves within misfit heterostructures.

Local-moment magnetism in Mn-based pnictides. Crispino, Matteo; Witt, Niklas; Gorni, Tommaso; Sangiovanni, Giorgio; de’ Medici, Luca. In Phys. Rev. B 113, 134434 (2026). 2025.

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We report a comprehensive study of electronic-correlation effects in Manganese-based antiferromagnetic pnictides BaMn\($_2$\)Pn\($_2$\) (Pn=P,As,Sb,Bi). Our density functional theory plus slave-spin mean-field simulations indicate that all the compounds lie on the strong-coupling side of an itinerant-to-localized moment crossover, corresponding to the critical interaction strength for the Mott transition in the high-temperature paramagnetic phase. We also show that the experimental Néel temperature of each compound scales with the distance from this crossover.

Entanglement across scales: Quantics tensor trains as a natural framework for renormalization. Rohshap, Stefan; Li, Jheng-Wei; Lorenz, Alena; Hasil, Serap; Held, Karsten; Kauch, Anna; Wallerberger, Markus. In Phys. Rev. Research 7, 043313 (2025). 2025.

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Understanding entanglement remains one of the most intriguing problems in physics. While particle and site entanglement have been studied extensively, the investigation of length or energy scale entanglement, quantifying the information exchange between different length scales, has received far less attention. Here, we identify the quantics tensor train (QTT) technique, a matrix product state-inspired approach for overcoming computational bottlenecks in resource-intensive numerical calculations, as a renormalization group method by analytically expressing an exact cyclic reduction-based real-space renormalization scheme in QTT language, which serves as a natural formalism for the method. In doing so, we precisely match the QTT bond dimension, a measure of length scale entanglement, to the number of rescaled couplings generated in each coarse-graining renormalization step. While QTTs have so far been applied almost exclusively to numerical problems in physics, our analytical calculations demonstrate that they are also powerful tools for mitigating computational costs in semi-analytical treatments. We present our results for the one-dimensional tight-binding model with n-th-nearest-neighbor hopping, where the 2n rescaled couplings generated in the renormalization procedure precisely match the QTT bond dimension of the one-particle Green's function.

Backscattering in Topological Edge States Despite Time-Reversal Symmetry. Erhardt, Jonas; Iannetti, Mattia; Dominguez, Fernando; Hankiewicz, Ewelina M.; Trauzettel, Björn; Profeta, Gianni; Sante, Domenico Di; Sangiovanni, Giorgio; Moser, Simon; Claessen, Ralph. In arXiv:2503.11497v2. 2025.

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Spin-momentum-locked edge states of quantum spin Hall insulators (QSHIs) provide a compelling platform for spintronic applications, owing to their intrinsic protection against backscattering from non-magnetic disorder. This protection emerges from time-reversal symmetry, which pairs Kramers partners of helical edge modes with opposite spin and momentum, thereby strictly forbidding elastic single-particle backscattering within the pair. Yet, contrary to the idealized notion of linear edge bands, the non-monotonic dispersions of realistic materials can host multiple Kramers pairs, reintroducing backscattering channels between them without violating time-reversal symmetry. Here, we investigate inter-Kramers pair backscattering in the non-linear edge bands of the QSHI indenene, highlighting a critical aspect of edge-state stability. Using quasiparticle interference in scanning tunneling spectroscopy -- a direct probe of backscattering -- we observe pairwise coupling between energy-degenerate Kramers pairs, while energy regions with only a single Kramers pair remain strictly protected. Supported by theoretical analysis, our findings provide an unprecedented experimental demonstration of edge state backscattering fully consistent with their underlying topological protection. This insight has profound implications for numerous QSHI candidates, emphasizing that the mere presence of gap-traversing edge modes does not inherently guarantee their protection against backscattering.

Optically Tunable Spin Transport in Bilayer Altermagnetic Mott Insulators. Sicheler, Niklas; Raimondi, Roberto; Sangiovanni, Giorgio; Re, Lorenzo Del. In arXiv:2508.06938v1. 2025.

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Altermagnets are a novel class of materials that combine antiferromagnetic spin ordering with non-relativistic spin splitting (NRSS) in their band structure, making them promising candidates for spintronics applications without requiring strong spin-orbit coupling. In this work, we investigate a two-dimensional bilayer Mott insulator that exhibits altermagnetic order. The interplay between spin and layer degrees of freedom gives rise to a complex symmetry-breaking pattern involving both magnetic and interlayer-coherent components. A key control parameter in the system is the layer polarization, which can be tuned via an external gate voltage. We show that applying an in-plane electric field with opposite signs in the two layers induces a polarization current that drives a spin current in each layer. While the polarization current is isotropic, the resulting spin current exhibits strong anisotropy and can be reversed by adjusting the photon energy. These findings suggest new avenues for manipulating spin transport in altermagnetic systems via electric and optical means.

Superconductivity governed by Janus-faced fermiology in strained bilayer nickelates. Ryee, Siheon; Witt, Niklas; Sangiovanni, Giorgio; Wehling, Tim O. In Phys. Rev. Lett. 135, 236003 (2025). 2025.

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High-temperature superconductivity in pressurized and strained bilayer nickelates (La,Pr)\($_3$\)Ni\($_2$\)O\($_7$\) has emerged as a new frontier. One of the key unresolved issues concerns the fermiology that underlies superconductivity. On both theoretical and experimental sides, no general consensus has been reached, and conflicting results exist regarding whether the relevant Fermi surface involves a \($γ$\) pocket -- a hole pocket with \($d_z^2$\)-orbital character centered at the Brillouin zone corner. Here, we address this issue by unveiling a Janus-faced role of the \($γ$\) pocket in spin-fluctuation-mediated superconductivity. We show that this pocket simultaneously induces dominant pair-breaking and pair-forming channels for the leading \($s_\pm$\)-wave pairing. Consequently, an optimal superconducting transition temperature \($T_\mathrmc$\) is achieved when the \($γ$\) pocket surfaces at the Fermi level, placing the system near a Lifshitz transition. This suggests that superconductivity can emerge, provided the maximum energy level of the \($γ$\) pocket lies sufficiently close to the Fermi level, either from below or above. Our finding not only reconciles two opposing viewpoints on the fermiology, but also naturally explains recent experiments on (La,Pr)\($_3$\)Ni\($_2$\)O\($_7$\) thin films, including the superconductivity under compressive strain, two conflicting measurements on the Fermi surface, and the dome shape of \($T_\mathrmc$\) as a function of hole doping.

Berry Curvature Dipole-induced Non-linear Hall Effect in Oxide Heterostructures. Joseph, Nesta Benno; Bandyopadhyay, Arka; Balram, Ajit C.; Narayan, Awadhesh. In arXiv:2510.20746v1. 2025.

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The observation of non-linear Hall effects in time-reversal invariant systems has established the intriguing role of band topology beyond Berry curvature in determining transport phenomena. Many of these non-linear responses owe their origin to the Berry curvature dipole (BCD), which, like the Berry curvature (monopole), is also an electronic band structure effect, but is routinely strongly constrained by crystalline symmetries. Here, we propose non-centrosymmetric transition metal oxide heterostructures as promising platforms for realizing and tuning BCD-induced non-linear Hall effects. Specifically, we investigate superlattices of the form \($(\mathrmBa(Os,Ir)\mathrmO_3)_n/(\mathrmBaTiO_3)_4$\) (\($n=1, 2$\)), comprising metallic perovskite layers (\($\mathrmBaOsO_3$\) or \($\mathrmBaIrO_3$\)) sandwiched between insulating ferroelectric \($\mathrmBaTiO_3$\) (BTO). The ferroelectric distortion in BTO breaks inversion symmetry of the superlattice, giving rise to a finite BCD with two symmetry-allowed components of equal magnitude and opposite sign. Our first-principles calculations demonstrate that the magnitude of the BCD -- and consequently the nonlinear Hall response -- can be effectively tuned by varying the number of metallic layers or the choice of the B-site cation in these \($\mathrmABO_3$\) perovskites. Since Rashba splitting and ferroelectric distortion in these systems are readily controllable via an external electric field or strain, the non-linear Hall response in these materials can be directly engineered. Our findings establish non-centrosymmetric oxide perovskite heterostructures as a versatile platform for exploring and manipulating BCD-driven non-linear transport phenomena.

Kagome metals. Sante, Domenico Di; Neupert, Titus; Sangiovanni, Giorgio; Thomale, Ronny; Comin, Riccardo; Zeljkovic, Ilija; Checkelsky, Joseph G.; Wilson, Stephen D. In Rev. Mod. Phys. 98, 015002 (2026). 2025.

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Three important driving forces for creating qualitatively new phases in quantum materials are the topology of the materials' electronic band structures, frustration in the electrons' motion or magnetic interactions, and strong correlations between their charge, spin, and orbital degrees of freedom. In very few material systems do all of these aspects come together to contribute on an equal footing to stabilize new electronic states with unprecedented properties; however the search for such systems can be guided by models of configurational motifs or key sublattices that can host such physics. One of the most fascinating structural motifs for realizing this rich interplay of frustration, electronic topology, and electron correlation effects is the kagome lattice. In this review, we provide an overview of the theoretical underpinnings driving the physics of kagome lattices, and we then discuss experimental progress in realizing novel states enabled by kagome networks in crystalline materials. Different material classes are discussed with an emphasis on the phenomenologies of their electronic states and how they map to interactions arising from their kagome lattices.

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