Strongly Correlated Altermagnetism

• Strongly correlated altermagnetism is a compensated magnetic phase with zero net magnetization that exhibits nonrelativistic, momentum-dependent spin splitting driven by strong electron correlations.
• It arises from mechanisms such as orbital order, superexchange interactions, and ligand hybridization, leading to observable d-wave spin textures and tunable spin conductivities.
• Material realizations span correlated metallic monolayers, Mott insulators, and Hund metals, with examples including YbMn₂Ge₂, La₂O₃Mn₂Se₂, CaCrO₃, and NiS₂.

Searching arXiv for papers on strongly correlated altermagnetism and the specific cited works. Strongly correlated altermagnetism denotes a regime in which altermagnetic order coexists with pronounced electron–electron interaction effects such as Mott or charge-transfer physics, Hund-metal behavior, orbital ordering, and strong local-moment formation. In this regime, compensated magnetic order with zero net magnetization can still exhibit nonrelativistic, momentum-dependent spin splitting of Bloch bands, but the microscopic origin and observable magnitude of that spin splitting are governed by correlation-induced orbital polarization, superexchange, bandwidth renormalization, ligand hybridization, and dynamical self-energies rather than by a weak-coupling band picture alone. Recent work has established that strongly correlated altermagnetism is not restricted to a single materials class: it appears in correlated metallic monolayers, Mott insulators, Hund metals, perovskite oxides, oxychalcogenides, and heavy-fermion candidates, with realizations ranging from orbital-order–driven $d$-wave metallic altermagnets to insulating local-moment systems with chiral magnons and symmetry-diagnosed resonant inelastic x-ray scattering responses (Jana et al., 26 Mar 2026, Zhang et al., 17 Jun 2026, Jungwirth et al., 28 Jun 2025).

1. Definition and symmetry structure

Altermagnetism is a collinear, compensated magnetic phase with zero net magnetization but without Kramers spin degeneracy of Bloch bands in the nonrelativistic limit. Unlike conventional collinear antiferromagnets, where sublattice-connecting antiunitary symmetries such as $\mathcal{PT}$ or translation–time-reversal enforce spin-degenerate bands, altermagnets break those protections while retaining combined spin–space symmetries that constrain a sign-changing spin splitting in momentum space (Jungwirth et al., 28 Jun 2025).

The review literature describes altermagnetism as a collinear compensated magnetically ordered phase with a $d$-, $g$-, or $i$-wave anisotropy and alternating spin polarization of the electronic structure in the position and momentum space (Jungwirth et al., 28 Jun 2025). In momentum space, the characteristic relation is an even-parity anisotropic mapping between opposite-spin dispersions, rather than a rigid Zeeman shift. For a $d$-wave altermagnet, the spin splitting follows a form factor such as

$\Delta E(\mathbf{k}) \sim \cos k_x - \cos k_y,$

with nodal planes where the splitting vanishes and changes sign across symmetry-related directions (Jungwirth et al., 28 Jun 2025).

Strongly correlated altermagnets preserve this symmetry logic but realize it in systems where electron correlations are comparable to or larger than the bare bandwidth. The relevant materials can be correlated metals, Mott insulators, or bad metals, and the spin-group classification remains applicable across both itinerant and local-moment limits (Jungwirth et al., 28 Jun 2025). What changes is the microscopic origin of the order parameter and the structure of the spectrum: coherent spin-split bands in weakly correlated cases can become renormalized quasiparticles, Hubbard bands, or magnonic excitations in correlated cases (Park et al., 18 Dec 2025, Zhang et al., 17 Jun 2026).

A recurrent symmetry distinction in the correlated literature is the absence of $\mathcal{PT}$ and of sublattice-connecting translation–time-reversal, together with the survival of rotational or mirror operations combined with spin or time-reversal transformations. In monolayer YbMn$_2$Ge$_2$, for example, $\mathcal{PT}$0 and diagonal mirror–time-reversal symmetries constrain a $\mathcal{PT}$1-wave spin texture while allowing giant nonrelativistic spin splitting away from symmetry-enforced nodal lines (Jana et al., 26 Mar 2026). In La$\mathcal{PT}$2O$\mathcal{PT}$3Mn$\mathcal{PT}$4Se$\mathcal{PT}$5, the low-temperature order breaks $\mathcal{PT}$6 and $\mathcal{PT}$7 but preserves a combined spin–space symmetry $\mathcal{PT}$8, producing $\mathcal{PT}$9-wave altermagnetism in a strongly correlated Lieb-lattice magnet (Zhang et al., 17 Jun 2026).

2. Correlation mechanisms beyond weak-coupling band altermagnetism

A central result of recent work is that strong correlations can generate altermagnetism spontaneously through orbital physics rather than merely renormalize an already symmetry-allowed band splitting. The clearest example is the correlation-driven orbital-order mechanism established for monolayer YbMn$d$0Ge$d$1, where electronic correlations in a multi-orbital antiferromagnet spontaneously produce antiferro-orbital order, which then generates giant nonrelativistic spin splitting with a $d$2-wave spin texture (Jana et al., 26 Mar 2026).

In that system, the low-energy Mn $d$3 and $d$4 orbitals are described by a two-orbital Hubbard–Kanamori model with anisotropic dispersions

$d$5

$d$6

with $d$7 and $d$8 (Jana et al., 26 Mar 2026). Correlations and $d$9 Fermi-surface nesting stabilize staggered orbital polarization,

$g$0

which, combined with spin–sublattice locking in the antiferromagnetic background, yields

$g$1

This produces the defining $g$2-wave altermagnetic texture and a nonrelativistic spin splitting of order $g$3–$g$4 eV near zone boundaries (Jana et al., 26 Mar 2026).

A broader theoretical advance is the demonstration that spontaneous altermagnetism can arise in a multi-orbital Mott insulator without relying on crystallographically pre-imposed altermagnetic symmetry. In a $g$5 three-orbital model on a square lattice, strong coupling generates a spontaneous altermagnetic Mott insulator through coexistence of staggered antiferromagnetic spin order and staggered orbital order (Kaushal et al., 26 Feb 2026). This work is notable because the required AFM+AFO combination violates the usual Goodenough–Kanamori expectations for a two-orbital system. The proposed resolution is the presence of a third, nearly half-filled orbital that contributes an additional antiferromagnetic superexchange channel, allowing the Goodenough–Kanamori rules to be circumvented and stabilizing a spontaneous altermagnetic Mott phase over a substantial parameter window (Kaushal et al., 26 Feb 2026).

The general review of symmetry and microscopy signatures emphasizes that strongly correlated altermagnets can emerge through several related mechanisms: superexchange in distorted perovskites, orbital-selective Mott physics, orbital-order–driven symmetry lowering, and even multipolar order in $g$6 systems (Jungwirth et al., 28 Jun 2025). In all of these cases, the same spin-group classification applies, but the order parameter may live in spin, orbital, or multipolar expectation values rather than in a weak-coupling spin-dependent self-energy (Jungwirth et al., 28 Jun 2025).

3. Material realizations across metals, insulators, and Hund systems

The current materials landscape spans correlated metals, Mott insulators, Hund metals, and heavy-fermion systems. The table summarizes representative realizations discussed in the recent literature.

Material	Regime	Key correlated-altermagnetic feature
Monolayer YbMn$g$7Ge$g$8	Correlated 2D metal	Orbital-order–driven $g$9-wave altermagnetism with $i$0 eV spin splitting (Jana et al., 26 Mar 2026)
La$i$1O$i$2Mn$i$3Se$i$4	Correlated insulator	Layered $i$5-wave altermagnet with robust local Mn moments and 2D short-range AFM correlations (Wei et al., 2024)
La$i$6O$i$7Mn$i$8Se$i$9 / La$d$0O$d$1Mn$d$2Se$d$3O$d$4 family context	Strongly correlated Lieb-lattice system	$d$5-wave altermagnetism revealed by circularly polarized RIXS (Zhang et al., 17 Jun 2026)
CaCrO$d$6	Hund metal	Strongly correlated metallic $d$7-wave altermagnet with non-Fermi-liquid behavior and heavy-fermion-like mass enhancement (Ouyang et al., 18 Jul 2025)
NiS$d$8	Mott–Hund system near MIT	Metallic altermagnet near a pressure-driven MIT with lifetime asymmetry between spin-up and spin-down quasiparticles (Park et al., 18 Dec 2025)
CeNiAsO	Heavy-fermion candidate	Strongly correlated $d$9-electron limit where localized 4f electrons suppress observable p-wave exchange splitting (Zhang et al., 1 Jun 2026)
NiS	Correlated NiAs-type system	Chemical-bonding-driven AMSS exceeding 1 eV for edge valence and conduction bands (Mandal et al., 2024)
CuAg(SO$\Delta E(\mathbf{k}) \sim \cos k_x - \cos k_y,$0)$\Delta E(\mathbf{k}) \sim \cos k_x - \cos k_y,$1	Doubly-strongly-correlated CT insulator	3D correlated altermagnet with Cu$\Delta E(\mathbf{k}) \sim \cos k_x - \cos k_y,$2 and Ag$\Delta E(\mathbf{k}) \sim \cos k_x - \cos k_y,$3 local moments (Jeschke et al., 2024)

Monolayer YbMn$\Delta E(\mathbf{k}) \sim \cos k_x - \cos k_y,$4Ge$\Delta E(\mathbf{k}) \sim \cos k_x - \cos k_y,$5 is the clearest correlated metallic realization. It combines moderate-to-strong Hubbard–Hund interactions, spontaneous antiferro-orbital order, metallicity, and giant nonrelativistic spin splitting in a stable 2D monolayer (Jana et al., 26 Mar 2026). The same work identifies an exceptionally large and gate-tunable transverse spin conductivity, making it a prototype of correlated altermagnetic spintronics (Jana et al., 26 Mar 2026).

La$\Delta E(\mathbf{k}) \sim \cos k_x - \cos k_y,$6O$\Delta E(\mathbf{k}) \sim \cos k_x - \cos k_y,$7Mn$\Delta E(\mathbf{k}) \sim \cos k_x - \cos k_y,$8Se$\Delta E(\mathbf{k}) \sim \cos k_x - \cos k_y,$9 is instead a Mott-like correlated insulator with high-spin Mn$\mathcal{PT}$0 moments, Néel order below about $\mathcal{PT}$1 K, and pronounced short-range 2D magnetic correlations above $\mathcal{PT}$2 (Wei et al., 2024). Its symmetry enforces a $\mathcal{PT}$3-type momentum dependence of nonrelativistic spin splitting, even though transport at low temperature is suppressed by the large gap (Wei et al., 2024). Closely related work on the same broader family establishes $\mathcal{PT}$4-wave altermagnetism through RIXS on a strongly correlated Lieb-lattice magnet and proves that the observed circular dichroism is a direct consequence of altermagnetic symmetry constraints rather than of experimental geometry (Zhang et al., 17 Jun 2026).

CaCrO$\mathcal{PT}$5 is presently the archetype of a strongly correlated metallic altermagnet treated with full dynamical correlations. DFT+DMFT reproduces its correlated metallic behavior, the incoherence peak seen in photoemission, a local ordered moment of $\mathcal{PT}$6/Cr in agreement with experiment, and a mass enhancement $\mathcal{PT}$7 (Ouyang et al., 18 Jul 2025). It also identifies CaCrO$\mathcal{PT}$8 as a Hund’s metal with non-Fermi-liquid behavior, heavy-fermion-like flat-band renormalization, and altermagnetic spin splitting protected on nodal planes $\mathcal{PT}$9 and $_2$0 (Ouyang et al., 18 Jul 2025).

NiS$_2$1 extends the field to a Mott–Hund system near a pressure-driven metal–insulator transition. It remains altermagnetic across the transition, but dynamic correlations reshape the metallic phase through momentum-dependent bandwidth renormalization and pronounced lifetime asymmetry between spin-up and spin-down quasiparticles (Park et al., 18 Dec 2025). This identifies a new correlated regime in which spin splitting must be understood simultaneously in terms of exchange fields, quasiparticle weights, and spin-dependent scattering rates (Park et al., 18 Dec 2025).

CeNiAsO provides an opposite extreme. It is a heavy-fermion candidate for p-wave altermagnetism, but high-resolution ARPES finds no resolvable near-$_2$2 exchange splitting on Ni 3d-derived bands across the Néel transitions (Zhang et al., 1 Jun 2026). DFT+U shows that once the Ce 4f electrons are treated as localized rather than itinerant, the residual p-wave splitting on the Ni 3d bands is reduced to only a few meV, below the effective experimental resolution (Zhang et al., 1 Jun 2026). This establishes an important boundary case for strongly correlated altermagnetism: symmetry may allow altermagnetic order, yet localized $_2$3 physics can suppress the observable single-particle signature expected from a weak-correlation picture (Zhang et al., 1 Jun 2026).

4. Electronic-structure fingerprints and the role of orbital and ligand chemistry

In strongly correlated altermagnets, the electronic signatures go beyond simple spin-split band structures. Orbital differentiation, ligand hybridization, Hubbard bands, and lifetime effects all reshape the observable spectrum.

The review of symmetry and spectroscopy signatures emphasizes that in strongly correlated altermagnets the coherent part of the spectral function retains the symmetry-governed altermagnetic nodal structure, while Hubbard bands, mass renormalization, and incoherent background alter the energy scales and visibility of the spin splitting (Jungwirth et al., 28 Jun 2025). This theme appears repeatedly in material-specific studies.

In Ca$_2$4RuO$_2$5, first-principles calculations reveal orbital-selective altermagnetism in the $_2$6 manifold: the nonrelativistic spin splitting is strong for $_2$7 and $_2$8 but strongly suppressed for $_2$9 (Cuono et al., 2023). The reason is not just different exchange splittings at $_2$0—$_2$1 eV for $_2$2 and $_2$3 eV for $_2$4—but also the dimensionality of the orbital sector. The $_2$5 states are effectively quasi-2D and remain nearly spin-degenerate along the relevant altermagnetic paths, whereas the more three-dimensional $_2$6 sector supports a clear altermagnetic splitting (Cuono et al., 2023). This establishes that strong correlations can make altermagnetism orbital-selective even within a single compound (Cuono et al., 2023).

In YVO$_2$7, the same study shows that altermagnetism survives across A-, C-, and G-type magnetic orders, with the Brillouin-zone pattern depending on the order and the nonrelativistic spin splitting increasing with the Coulomb repulsion $_2$8 (Cuono et al., 2023). This is one of the clearest demonstrations that in a Mott insulator the magnitude of altermagnetic splitting can be correlation-enhanced rather than suppressed (Cuono et al., 2023).

NiS provides a complementary chemical-bonding perspective. First-principles and Slater–Koster tight-binding analysis in the NiAs prototype show that altermagnetic spin splitting is controlled not only by spin order and symmetry but also by explicit orbital participation and second-neighbor nonmagnetic-atom interactions (Mandal et al., 2024). In the single-orbital limit, nearest-neighbor Ni–S hoppings alone do not produce AMSS; second-neighbor S–S′ hopping is required to modulate the intra-sublattice interactions differently for the two AFM sublattices (Mandal et al., 2024). In the multi-orbital case, altermagnetism appears naturally once multiple Ni and S orbitals are active, and S $_2$9 is particularly important: removing S-$\mathcal{PT}$00 destroys altermagnetism, while removing S-$\mathcal{PT}$01 or S-$\mathcal{PT}$02 does not (Mandal et al., 2024). For the edge valence and conduction bands, the AMSS exceeds $\mathcal{PT}$03 eV and increases with correlation, reaching about $\mathcal{PT}$04 eV for the top valence pair at $\mathcal{PT}$05 eV (Mandal et al., 2024).

The importance of ligand chemistry is further generalized in the comparative study of MnF$\mathcal{PT}$06, MnTe, and RuO$\mathcal{PT}$07. There, strong local Mn 3$\mathcal{PT}$08 correlations in MnF$\mathcal{PT}$09 produce a visible-range Mott gap and markedly localize the Mn 3$\mathcal{PT}$10 electrons, narrowing the spin-resolved bandwidth and suppressing spin-band splitting (Kang et al., 14 May 2026). MnTe, by contrast, combines strong local Mn moments with robust Mn 3$\mathcal{PT}$11–Te 5$\mathcal{PT}$12 hybridization and retains a spin-band splitting of about $\mathcal{PT}$13 eV, making it an “ideal platform for altermagnetism” within a correlated local-moment setting (Kang et al., 14 May 2026). RuO$\mathcal{PT}$14 occupies the itinerant limit: it is described as a Pauli paramagnet with vanishing local moments even in the antiferromagnetic phase, yet it exhibits substantial spin-band splitting and thus itinerant altermagnetic behavior (Kang et al., 14 May 2026). A plausible implication is that strong local correlations alone do not guarantee large altermagnetic splitting; the ligand environment must also preserve sufficient itinerancy and orbital mixing (Kang et al., 14 May 2026).

5. Collective excitations, spectroscopy, and transport

Strongly correlated altermagnetism is not limited to single-particle band splitting. It also restructures collective modes and transport responses in ways that are often more accessible in insulating compounds than conventional charge transport.

The most direct recent spectroscopic advance is the demonstration of $\mathcal{PT}$15-wave altermagnetism by circularly polarized RIXS in La$\mathcal{PT}$16O$\mathcal{PT}$17Mn$\mathcal{PT}$18Se$\mathcal{PT}$19 (Zhang et al., 17 Jun 2026). The RIXS spectra show a $\mathcal{PT}$20-wave-symmetry circular dichroism in the magnetic excitations that vanishes in the paramagnetic phase (Zhang et al., 17 Jun 2026). Symmetry analysis and exact diagonalization prove that this dichroism is intrinsic to the altermagnetic spin–space symmetry and does not require resolved magnon branch splitting (Zhang et al., 17 Jun 2026). The observed pattern obeys

$\mathcal{PT}$21

which is precisely the expected $\mathcal{PT}$22-wave constraint for the altermagnetic phase in that geometry (Zhang et al., 17 Jun 2026).

Theoretical work on spontaneous altermagnetism in a three-orbital Mott insulator predicts an additional layer of correlated dynamics: chirally split magnons generated entirely by interaction-induced spin–orbital order (Kaushal et al., 26 Feb 2026). In that model, the magnon splitting decays as $\mathcal{PT}$23, indicating a fourth-order superexchange origin, and the magnon chirality transforms with the same $\mathcal{PT}$24-wave symmetry as the electronic altermagnetic order (Kaushal et al., 26 Feb 2026). With weak atomic SOC and a small in-plane field, the same system supports a hybrid chiral magnon–orbiton mode carrying finite orbital polarization and producing longitudinal and transverse orbital conductivities under a thermal gradient (Kaushal et al., 26 Feb 2026). This suggests that in strongly correlated altermagnets the orbital sector can remain active at the level of collective transport, not only static order.

Transport in correlated metallic altermagnets is exemplified by monolayer YbMn$\mathcal{PT}$25Ge$\mathcal{PT}$26. In the absence of SOC, the transverse spin conductivity is dominated by a Fermi-surface contribution

$\mathcal{PT}$27

and reaches a peak value of about $\mathcal{PT}$28 in 2D units, with a $\mathcal{PT}$29 angular dependence and sign reversal under gating (Jana et al., 26 Mar 2026). The strong gate tunability follows from the metallic correlated state and the giant $\mathcal{PT}$30 eV spin splitting at the Fermi surface (Jana et al., 26 Mar 2026).

Perovskite model studies reach a related conclusion from a different microscopic route. In distorted AFM perovskites, spin-dependent anisotropic hopping in a multiorbital Hubbard framework generates a nonrelativistic transverse spin current without SOC and an anomalous Hall effect once SOC and next-nearest-neighbor hopping are included (Naka et al., 2024). These results underscore that in strongly correlated oxides the cross-correlation of spin, charge, and lattice degrees of freedom is a natural consequence of altermagnetic symmetry and orbital-selective hopping (Naka et al., 2024).

6. Correlated competition, renormalization, and open controversies

A recurring misconception is that strongly correlated altermagnetism is simply weak-coupling altermagnetism with a larger local moment. The recent literature shows that this is not generally correct.

The NiS$\mathcal{PT}$31 study is explicit on this point. Static correlations, modeled at the DFT+$\mathcal{PT}$32 level, enhance local moments and therefore tend to uniformly increase the altermagnetic spin splitting. Dynamic correlations, however, produce momentum-dependent bandwidth renormalization and can reduce the spin splitting for some bands even when the ordered moment is held fixed (Park et al., 18 Dec 2025). They also generate a pronounced lifetime asymmetry between spin-up and spin-down quasiparticles, amplified by the particle–hole asymmetry promoted by Hund’s correlations (Park et al., 18 Dec 2025). A plausible implication is that in correlated altermagnetic metals the observability of spin splitting can be controlled as much by spin-dependent coherence as by exchange energy scales.

CaCrO$\mathcal{PT}$33 reaches a related conclusion from the opposite methodological direction. DFT+$\mathcal{PT}$34 predicts an insulating ferromagnetic ground state inconsistent with experiment, whereas DFT+DMFT recovers the correlated metallic C-type AFM phase and its altermagnetic splitting (Ouyang et al., 18 Jul 2025). This is one of the clearest cases showing that static mean-field correlations are insufficient for some strongly correlated altermagnets and that dynamical methods are required to capture the coexistence of metallicity, incoherent spectral weight, and nonrelativistic spin splitting (Ouyang et al., 18 Jul 2025).

Another controversy concerns whether all symmetry-allowed correlated AFM materials display experimentally visible altermagnetic splitting. CeNiAsO demonstrates that the answer is no. Although its low-temperature phase is theoretically a p-wave altermagnet and transport exhibits macroscopic signatures consistent with the proposed magnetic order, high-resolution ARPES sees no resolvable near-$\mathcal{PT}$35 exchange splitting on the Ni 3$\mathcal{PT}$36 bands (Zhang et al., 1 Jun 2026). The work identifies localized Ce 4$\mathcal{PT}$37 character and reduced low-energy $\mathcal{PT}$38–$\mathcal{PT}$39 hybridization as the reason the transferred splitting on the Ni 3$\mathcal{PT}$40 conduction states falls to only a few meV (Zhang et al., 1 Jun 2026). This does not invalidate the altermagnetic symmetry classification, but it shows that single-particle band splitting can be strongly renormalized or effectively hidden in heavy-fermion systems (Zhang et al., 1 Jun 2026).

A further correlated competition appears in two-orbital models near Van Hove singularities. There, intrinsic altermagnetism can preempt Stoner ferromagnetism even when the conventional Stoner conditions are met, with a quantum phase transition between altermagnetism and ferromagnetism at a critical Hund’s coupling $\mathcal{PT}$41 (Lu et al., 1 Oct 2025). The implication is that in multiorbital correlated metals, $\mathcal{PT}$42 spin fluctuations need not culminate in ferromagnetism; altermagnetic order can be the leading instability within the same momentum sector (Lu et al., 1 Oct 2025).

An additional frontier concerns superconductivity. Constrained-path quantum Monte Carlo on a Hubbard model with spin-anisotropic hopping finds that increasing anisotropy suppresses long-range antiferromagnetic order and significantly enhances effective $\mathcal{PT}$43-wave pairing correlations near half filling (Li et al., 18 May 2025). This study frames the result as a doping-free route to unconventional superconductivity mediated by short-range spin fluctuations in an altermagnetic background (Li et al., 18 May 2025). While this is a model result rather than a material realization, it strengthens the analogy between higher-partial-wave magnetism and higher-partial-wave superconductivity already emphasized in the review literature (Jungwirth et al., 28 Jun 2025).

7. Broader significance and design principles

The emerging design principles for strongly correlated altermagnetism combine symmetry criteria with correlation and bonding criteria.

One route starts from multi-orbital AFM metals or insulators with orthogonally anisotropic orbitals such as $\mathcal{PT}$44 and $\mathcal{PT}$45, moderate-to-strong Hubbard–Hund interactions, and Fermi-surface nesting or superexchange tendencies favoring staggered orbital order (Jana et al., 26 Mar 2026, Kaushal et al., 26 Feb 2026). This is the route realized in monolayer YbMn$\mathcal{PT}$46Ge$\mathcal{PT}$47 and in spontaneous altermagnetic Mott-insulator models (Jana et al., 26 Mar 2026, Kaushal et al., 26 Feb 2026).

A second route exploits structural distortions and orbital-dependent hopping in perovskites and related oxides. Octahedral tilts, GdFeO$\mathcal{PT}$48-type distortions, and orbital order create sublattice-dependent anisotropic hopping, which, combined with $\mathcal{PT}$49 AFM order, yields nonrelativistic spin splitting and spin-current responses in a strongly correlated oxide platform (Naka et al., 2024, Jungwirth et al., 28 Jun 2025).

A third route emphasizes ligand chemistry. Strong correlations are beneficial only if ligand-assisted hybridization preserves sufficient band dispersion. MnTe and NiS illustrate this balance: large local moments coexist with strong metal–ligand hybridization and produce spin splittings of order $\mathcal{PT}$50 eV (Kang et al., 14 May 2026, Mandal et al., 2024). MnF$\mathcal{PT}$51 illustrates the opposite case, where stronger localization suppresses the splitting (Kang et al., 14 May 2026).

A fourth route targets Hund metals and systems near a Mott transition. CaCrO$\mathcal{PT}$52 and NiS$\mathcal{PT}$53 show that Hundness and proximity to a metal–insulator transition can generate heavy quasiparticles, non-Fermi-liquid behavior, and strong spin-dependent lifetime effects while preserving altermagnetic symmetry (Ouyang et al., 18 Jul 2025, Park et al., 18 Dec 2025). This suggests that Hund metals provide an especially promising class for novel correlated altermagnetic phenomena (Ouyang et al., 18 Jul 2025).

Finally, the heavy-fermion case of CeNiAsO indicates an important cautionary principle: strong correlations can also suppress the observable single-particle band signature when the magnetic order resides on localized orbitals only weakly hybridized with conduction states (Zhang et al., 1 Jun 2026).

Taken together, these results establish strongly correlated altermagnetism as a broad materials and theoretical category rather than a narrow extension of itinerant band altermagnetism. It includes orbital-order–driven metallic altermagnets, spontaneous Mott altermagnets, orbital-selective oxide altermagnets, Hund-metal altermagnets, chemically bonded CT-insulating altermagnets, and heavy-fermion candidates with renormalized or hidden exchange splitting (Jana et al., 26 Mar 2026, Kaushal et al., 26 Feb 2026, Cuono et al., 2023, Ouyang et al., 18 Jul 2025, Park et al., 18 Dec 2025, Jeschke et al., 2024). The common thread is that compensated magnetic order and higher-partial-wave spin symmetry persist, while the microscopic realization and observability of the altermagnetic spin texture are controlled by the same strong-correlation mechanisms that define modern correlated-electron physics.