{"id":"0dbfa4b4-5c66-45fb-9319-b2e335b33846","arxiv_id":"2411.16378","paper_version":1,"verdict":"CONDITIONAL","confidence":"MODERATE","novelty_score":6.0,"correctness_risk":"medium","formal_verification":"none","parameter_count":5,"one_line_summary":"P-wave magnets (time-reversal-preserving, inversion-breaking coplanar magnets) show a large anisotropic non-relativistic Edelstein effect, with CeNiAsO predicted to be 25 times more efficient than prior materials.","lead":"Electric fields can create spin polarization in p-wave magnets without spin-orbit coupling, a non-relativistic Edelstein effect with out-of-plane spin accumulation. A first-principles calculation identifies CeNiAsO as an unusually efficient converter, with a computed response about 25 times larger than existing non-relativistic and relativistic Edelstein materials.","discovery_kind":"new_application","skeptic_critique":{"model":"deepseek-v4-flash","headline":"The 25x NREE claim for CeNiAsO rests on a commensurate magnetic order that appears to contradict the cited experimental report (Wu et al., PRL 122, 197203, 'Incommensurate Magnetism'); if the true order is incommensurate, the [C2z||t_a/2] symmetry and the predicted χ_zx/χ_zz tensor are not exact.","rationale":"The paper makes a strong quantitative claim that CeNiAsO exhibits a 25x larger non-relativistic Edelstein susceptibility than previously reported systems. This claim rests on the identification of CeNiAsO as a p-wave magnet with the spin-space symmetry [C2⊥||t]. The symmetry analysis and tight-binding models are internally consistent and provide a valuable framework for NREE in p-wave magnets. However, the material-specific prediction depends on the experimental magnetic ground state of CeNiAsO. The paper asserts a commensurate coplanar order and cites Wu et al. (PRL 122, 197203), whose title states 'Incommensurate Magnetism Near Quantum Criticality in CeNiAsO'. This is an apparent contradiction: if the ground state is incommensurate, the exact T-t symmetry used to derive the χ_zx/χ_zz tensor and the nodal line is not a symmetry of the crystal. Consequently, the 13 ℏÅ/V value and the 25x enhancement are not trustworthy as presented. This is the most load-bearing concern because it attacks the central demonstration rather than a peripheral parameter. The issue is addressable: one can check the cited reference and, if needed, recompute with the correct magnetic structure. A secondary but related concern is that the magnitude in Eq. (3) scales as 1/Γ and the broadening Γ for CeNiAsO is not stated, making the quantitative number non-reproducible. Both issues are fixable, so a conditional acceptance (with requests to verify the magnetic order and state Γ) is appropriate rather than rejection. The qualitative prediction for p-wave magnets as a class remains plausible and well-motivated.","tokens_in":11955,"tokens_out":6690,"duration_ms":59369,"concrete_test":"Read the experimental magnetic structure in Wu et al., PRL 122, 197203, and determine the propagation vector and magnetic space group. If the order is incommensurate, recompute the NREE for CeNiAsO in a supercell accommodating the incommensurate wavevector (or via an incommensurate symmetry analysis) and compare the resulting χ_zx/χ_zz with the commensurate values; if the components change significantly or the response drops, the 25x claim is unsupported.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central quantitative claim—13 ℏÅ/V and 25x enhancement for CeNiAsO—depends on the material realizing the p-wave spin symmetry [C2⊥||t] with a commensurate translation t_a/2. The paper states (Section 'Material Candidate: CeNiAsO') that CeNiAsO 'shows a co-planar commensurate magnetic order' and cites Wu et al. (Ref. [47], PRL 122, 197203). However, the title of that reference is 'Incommensurate Magnetism Near Quantum Criticality in CeNiAsO', implying an incommensurate propagation vector. If the magnetic structure is incommensurate, the operation [C2z||t_a/2] is not an exact symmetry of the crystal; the T-t symmetry that preserves TRS in momentum space is lost, and the symmetry-allowed tensor form (χ_zx and χ_zz only) and the nodal-line protection are not strictly valid. The NREE susceptibility could acquire additional components or be suppressed by the incommensurate modulation, so the 25x comparison with LuFeO3 and Rashba systems is not established for CeNiAsO. This is a factual discrepancy with the cited literature, not a mere parameter choice; it should be resolved before the material-specific prediction is accepted. (A secondary issue: the magnitude of the intra-band response in Eq. (3) scales as 1/Γ, and the Γ used for CeNiAsO is not stated, so even the quoted 13 ℏÅ/V is not reproducible without the missing broadening.)","agreement_with_reader":"agree"},"referee_report":{"model":"deepseek-v4-flash","summary":"The paper proposes a non-relativistic Edelstein effect (NREE) in p-wave magnets, i.e., coplanar non-collinear magnets with a combined spin-rotation-and-translation symmetry [C2⊥||t] that preserves time-reversal symmetry in momentum space. Using Kubo linear response, the authors compute the NREE susceptibility in a minimal four-band model and in a Kagome-lattice model, finding a large, strongly anisotropic, out-of-plane spin polarization. They then perform DFT-based Wannier tight-binding calculations for CeNiAsO and report a unit-cell-integrated NREE susceptibility of about 13 ℏÅ/V, which they state is 25 times larger than the values for LuFeO3 and for archetypal relativistic Rashba/topological-insulator systems. The paper concludes that p-wave magnets are promising materials for efficient charge-to-spin conversion without spin-orbit coupling.","tokens_in":12284,"tokens_out":8422,"duration_ms":77931,"significance":"The conceptual advance is significant: identifying a non-relativistic, exchange-driven charge-to-spin conversion mechanism in p-wave magnets, with a distinctive out-of-plane polarization and strong anisotropy, would broaden the materials palette for spintronics beyond heavy-element SOC systems. The symmetry-based classification and the explicit model calculations are strengths; the minimal-model and Kagome results are internally consistent and the tensor forms follow from the stated spin group. The DFT calculation for CeNiAsO is a concrete material prediction, but its validity depends on assumptions about the magnetic ground state and on numerical inputs that are not fully disclosed in the main text. If the material-specific claim is confirmed, the work would be an important step toward practical NREE devices; however, the current manuscript leaves the central quantitative claim under-supported.","major_comments":[{"comment":"The paper states that CeNiAsO 'shows a co-planar commensurate magnetic order' and cites Wu et al. (Ref. [47]), whose title is 'Incommensurate Magnetism Near Quantum Criticality in CeNiAsO.' This is a direct factual discrepancy: the cited experimental work reports an incommensurate magnetic ground state. The DFT calculation constrains the moments to a commensurate coplanar order with the exact spin-space symmetry [C2z||t_a/2], but if the true order is incommensurate, that symmetry is not exact, and the derived tensor form (only χ_zx and χ_zz) and the nodal-line protection are not strictly valid. The 13 ℏÅ/V susceptibility could be modified or averaged away. The authors must clarify the experimental magnetic structure, justify the commensurate approximation used in the calculation, or explicitly reframe the CeNiAsO result as a hypothetical commensurate phase rather than a prediction for the physical ground state.","section":"Material Candidate: CeNiAsO"},{"comment":"The intra-band susceptibility in Eq. (3) scales as 1/Γ, where Γ is the quasiparticle broadening. The main text specifies Γ = 0.1 eV for the minimal model and Γ = 0.01 eV for the Kagome model, but it never reports the Γ used for the Wannier tight-binding calculation of CeNiAsO. Without this value, the quoted absolute magnitude of 13 ℏÅ/V is not reproducible. Please state the Γ value (or the range of values) used in the material calculation and discuss how the claimed enhancement depends on this parameter.","section":"Methods / Eq. (3)"},{"comment":"The abstract and the concluding paragraph claim the CeNiAsO NREE is '25 times larger' than the 'maximally achieved relativistic EE' and than 'other reported NREE,' but the numerical comparison in the main text is only made against LuFeO3 (0.5 ℏÅ/V, giving a factor of about 26). The corresponding value for the relativistic benchmark (α-Sn, Ref. [20]) or for the Rashba 2DEG in comparable units is not given. Moreover, the Rashba 2DEG susceptibility is a sheet quantity (units ℏ/V·Å) while the CeNiAsO value is a unit-cell-integrated bulk quantity (units ℏÅ/V), so the direct comparison may be dimensionally inconsistent. Please provide the specific benchmark value used and, if necessary, recast the comparison in a consistent dimensional framework.","section":"Abstract and Discussion"}],"minor_comments":[{"comment":"The text above Eq. (2) calls the object a 'spin-current response function,' but the equation and the surrounding discussion refer to the spin-density response to an electric field; please correct the terminology.","section":"Eq. (2)"},{"comment":"The caption states that dashed curves show 'modifications of the specific components in the presence of SOC,' but the Methods describe calculations with constrained moments and with SOC switched off. It would be helpful to state explicitly how the SOC-included results were obtained (e.g., a separate DFT calculation with SOC, or a perturbative treatment).","section":"Fig. 4f"},{"comment":"The phrase 'the much larger spin-splitting (almost 2 orders of magnitude larger) relative to the relativistic EE' is a quantitative claim but no source or figure is given in the main text; please provide a reference or move the quantitative statement to the SI.","section":"Introduction"},{"comment":"Ref. [35] is cited as 'Arxiv Prepr.'; please update it with the published version or a complete arXiv identifier.","section":"References"},{"comment":"The word 'demonstrate' overstates what is a theoretical prediction; consider using 'show' or 'predict.'","section":"Abstract"}],"recommendation":"major_revision","confidential_remarks":"The paper comes from a leading group in the field and the symmetry framework is credible. The most serious issue is the discrepancy between the assumed commensurate magnetic order of CeNiAsO and the incommensurate order reported in the cited experimental paper; this needs to be resolved before the material-specific claim can be accepted. The missing Γ value is a straightforward but important reproducibility issue. The comparison with relativistic benchmarks also needs clarification. I would be willing to reconsider after revision."},"author_rebuttal":null,"desk_editor":{"model":"deepseek-v4-flash","letter":"Colleague,\n\nThe core idea here is worth your time. The paper takes the p-wave magnet concept (T-t symmetry, TRS preserved in momentum space) and works out the Edelstein response from exchange-driven spin splitting alone, without SOC. That is a real conceptual step beyond the earlier non-collinear NREE papers, which all broke TRS. The symmetry argument is clean and the tensor form (only chi_zx and chi_zz) follows directly from the spin group. The tight-binding models are simple and internally consistent, and the Kagome calculation gives a nice angular signature that could be measured. I buy the qualitative claim: p-wave magnets should give a large, anisotropic, out-of-plane Edelstein response.\n\nWhat the paper does well: the Kubo machinery is standard, the T-even/T-odd decomposition is clearly explained, and the model-level comparison with Rashba 2DEG and 3Q AFM is honest. The DFT calculation for CeNiAsO is a genuine first-principles effort with constrained moments, no fitted parameters in the response itself. The authors also explicitly show which susceptibility components appear only when SOC is added, which is a good calibration strategy.\n\nThe soft spots are real but concentrated in the material-specific headline. First, the 13 ℏÅ/V number depends on the quasiparticle broadening Γ through the 1/Γ factor in Eq. (3), and the main text never states the Γ used for CeNiAsO. That alone makes the quantitative claim not reproducible as written. Second, the cited experimental reference for the magnetic order is Wu et al., PRL 122, 197203, titled \"Incommensurate Magnetism Near Quantum Criticality in CeNiAsO.\" The paper calls the order commensurate and imposes the [C2z||t_a/2] symmetry. If the true order is incommensurate, that symmetry is approximate at best, and the protected tensor form and the 25x enhancement could be modified. The authors may have newer information or the supplemental may clarify this, but as it stands there is a factual tension with the cited literature. This is not a fatal flaw in the general mechanism, but it means the CeNiAsO prediction is conditional. The PBE treatment of Ce 4f electrons without an onsite Hubbard U is a third concern, though for a metallic response it may be less severe.\n\nWho is this for? Anyone working on spin-charge conversion, altermagnetism, or non-collinear magnets. The symmetry-based route to a non-relativistic Edelstein effect is the real contribution, and the material prediction is a testable target even if the exact ordering needs another look. My verdict: this deserves a serious referee. The referee should ask for the Γ value, a clearer discussion of the commensurate versus incommensurate order (preferably with the experimental propagator), and a robustness check of the response against a small symmetry-breaking perturbation. With those addressed, the paper could be quite influential.\n\nRecommendation: send it to review, with emphasis on the material-specific claims.","headline":"A solid symmetry-based prediction of a non-relativistic Edelstein effect in p-wave magnets, with a concrete material proposal that needs a sharper check on the experimental magnetic order and the quasiparticle broadening.","tokens_in":12929,"tokens_out":736,"would_cite":true,"duration_ms":9565,"reading_group":"yes","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":[],"model":"deepseek-v4-flash","headline":"Coplanar p-wave magnets convert charge to spin up to 25 times more efficiently than the best spin-orbit-based materials, without needing heavy elements.","keywords":["Edelstein effect","non-relativistic Edelstein effect","p-wave magnets","spin-charge conversion","CeNiAsO","coplanar non-collinear magnetism","Kubo linear response","spin-orbit-free spintronics"],"falsifier":"A spin-torque ferromagnetic resonance or magneto-optical Kerr measurement of current-induced spin density in CeNiAsO would settle it: if the out-of-plane susceptibility $\\chi^{zx}$ comes out near the relativistic baseline (about 0.5 $\\hbar$ Å/V) rather than the predicted 13 $\\hbar$ Å/V, or if the dominant spin polarization is in-plane rather than out-of-plane, the central claim would be contradicted.","tokens_in":11706,"feed_emoji":"🧲","tokens_out":14361,"duration_ms":112094,"temperature":0.7,"pith_summary":"Spin-charge conversion, the Edelstein effect, has generally been thought to require spin-orbit coupling and therefore heavy elements in non-centrosymmetric crystals. This paper argues that coplanar p-wave magnets, whose non-collinear magnetic order combines a 180-degree spin rotation with a lattice translation, produce a purely exchange-driven Edelstein effect with no spin-orbit coupling at all. The response is strongly anisotropic, with spin polarization pointing out of the plane of the magnetic order, and in the candidate material CeNiAsO it reaches about 13 $\\hbar$ Å/V, roughly 25 times the best reported relativistic Rashba value and the non-relativistic value in LuFeO$_3$. If correct, this would make light-element magnets viable for efficient charge-to-spin conversion in spintronic devices.","feed_headline":"CeNiAsO turns charge into spin 25x better with no heavy elements","feed_subtitle":"Spin polarization arises from magnetic order alone, not spin-orbit coupling, opening lighter spintronics.","key_machinery":"The carrier of the argument is the spin-space-group symmetry $[C_{2\\perp}\\|\\mathbf{t}]$: a 180-degree rotation of spin space about an axis perpendicular to the plane of the coplanar spins combined with a translation by half a lattice vector. In a p-wave magnet this symmetry survives while inversion is broken, forcing the spin-polarization direction in the band structure to be perpendicular to the spin plane and producing the odd-parity p-wave spin splitting. The response is then calculated with Kubo linear response; the dominant term is the intra-band Fermi-surface contribution, which is even under time reversal, while the inter-band Berry-curvature-like term is forbidden because p-wave magnets preserve time-reversal symmetry in momentum space through the $\\mathcal{T}\\mathbf{t}$ operation. Exchange-driven hopping $t_J$ rather than spin-orbit coupling controls the magnitude, which is why light-element candidates can compete.","core_discovery":"The paper's central claim is that the non-relativistic Edelstein effect (NREE) exists in p-wave magnets: magnets with coplanar non-collinear order whose spin-space group contains the element $[C_{2\\perp}\\|\\mathbf{t}]$—a 180° spin rotation about an axis perpendicular to the spin plane followed by a translation. This symmetry forces the band structure to split into opposite out-of-plane spin polarizations with odd-parity p-wave character, while the combined time-reversal-and-translation symmetry $\\mathcal{T}\\mathbf{t}$ keeps time-reversal symmetry in momentum space and zero net magnetization. Under an applied electric field, the intra-band Fermi-surface term of the Kubo response produces an out-of-plane spin accumulation with only $\\chi^{zx}$ and $\\chi^{zz}$ components finite; the inter-band T-odd term vanishes. In density-functional-theory calculations on CeNiAsO with spin-orbit coupling switched off, the integrated $\\chi^{zx}$ susceptibility is about 13 $\\hbar$ Å/V, 25 times larger than the best reported relativistic Rashba value and the NREE of LuFeO$_3$, establishing p-wave magnets as high-efficiency non-relativistic spin-charge converters.","pith_inferences":["By the same symmetry logic, other coplanar non-collinear magnets carrying the $[C_{2\\perp}\\|\\mathbf{t}]$ element should show the same out-of-plane-only NREE tensor, so a systematic computational screen of such magnetic orders could turn up materials with even larger responses than CeNiAsO.","The calculation fixes the magnetic order to an exact commensurate pattern, whereas the experimentally reported magnetism in CeNiAsO can be incommensurate; if the real order breaks the $[C_{2z}\\|\\mathbf{t}_{a/2}]$ symmetry, the predicted 25-fold enhancement may be reduced or averaged away, and this is a testable open question.","One could test the mechanism directly by comparing in-plane and out-of-plane Edelstein responses in a heavy-element candidate: a dominant out-of-plane component would confirm that exchange-driven NREE, not spin-orbit coupling, is doing the work.","If the NREE is as strong as predicted, current-driven manipulation of the coplanar order itself—analogous to spin-orbit torques but without spin-orbit coupling—becomes a plausible route, which the paper only gestures at."],"forward_implications":["Charge-to-spin conversion no longer requires heavy elements or inversion-breaking crystal fields; coplanar p-wave magnets with light elements should show Edelstein responses comparable to or larger than standard spin-orbit systems.","The NREE tensor in p-wave magnets has only out-of-plane susceptibility components, so rotating the electric-field direction or measuring the spin-polarization direction cleanly distinguishes this effect from the in-plane Rashba Edelstein effect.","CeNiAsO, with its predicted susceptibility of about 13 $\\hbar$ Å/V, becomes a concrete candidate material for efficient spin-orbit-torque-type devices based on a non-relativistic mechanism.","The vanishing of the inter-band contribution means the effect is governed entirely by the Fermi-surface intra-band term, giving a transparent single-band picture of the spin accumulation.","The angular dependence of the NREE in the Kagome model shows a nodal direction independent of chemical potential, providing a sharp experimental signature for p-wave magnets."],"supporting_citations":[{"why":"Establishes the p-wave magnet concept, the $[C_{2\\perp}\\|\\mathbf{t}]$ spin symmetry, and CeNiAsO as a candidate material.","marker":"[35]"},{"why":"Provides the baseline NREE value in LuFeO$_3$ and the 3Q non-coplanar antiferromagnet model used for comparison.","marker":"[33]"},{"why":"Supplies the best reported relativistic Rashba Edelstein value (α-Sn films) against which CeNiAsO is compared.","marker":"[20]"},{"why":"Gives the original Edelstein effect and the Rashba 2DEG formula used for the minimal-model comparison.","marker":"[6]"},{"why":"Provides the spin-symmetry classification that restricts collinear magnets to even-parity spin splitting and motivates the search for p-wave magnets.","marker":"[36]"},{"why":"Reports the experimental magnetic order of CeNiAsO, the input on which the symmetry and the NREE calculation rest.","marker":"[47]"}],"fun_headline_variants":["Spin-charge conversion 25x stronger without spin-orbit coupling","Magnetic order alone gives 25x spin-charge conversion in CeNiAsO","CeNiAsO p-wave magnet converts charge to spin 25x more efficiently","Edelstein effect without spin-orbit gives 25x boost","P-wave magnet delivers 25x spin-charge conversion sans spin-orbit"],"cache_read_input_tokens":3200,"weakest_assumption_plain":"The whole result hinges on CeNiAsO having exactly the periodic, all-spins-in-one-plane magnetic pattern the calculation assumes; if the real magnetic order is incommensurate or its symmetry is only approximate, the tensor components and the 25-fold enhancement could change or wash out.","fun_headline_variants_meta":{"raw":{"variants":["Spin-charge conversion 25x stronger without spin-orbit coupling","Magnetic order alone gives 25x spin-charge conversion in CeNiAsO","CeNiAsO p-wave magnet converts charge to spin 25x more efficiently","Edelstein effect without spin-orbit gives 25x boost","P-wave magnet delivers 25x spin-charge conversion sans spin-orbit"]},"model":"deepseek-v4-flash","effort":"low","cost_usd":0.001529,"raw_usage":{"total_tokens":6143,"prompt_tokens":989,"completion_tokens":5154,"prompt_tokens_details":{"cached_tokens":384},"prompt_cache_hit_tokens":384,"prompt_cache_miss_tokens":605,"completion_tokens_details":{"reasoning_tokens":5054}},"tokens_in":605,"tokens_out":5154,"duration_ms":35388,"temperature":1.0,"reasoning_tokens":5054,"cache_read_input_tokens":384,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-08-12T13:11:53.498065+00:00","model_set":{"reader":"deepseek-v4-flash"},"falsifier":"A spin-torque ferromagnetic resonance or magneto-optical Kerr measurement of current-induced spin density in CeNiAsO would settle it: if the out-of-plane susceptibility $\\chi^{zx}$ comes out near the relativistic baseline (about 0.5 $\\hbar$ Å/V) rather than the predicted 13 $\\hbar$ Å/V, or if the dominant spin polarization is in-plane rather than out-of-plane, the central claim would be contradicted.","supporting_citations":[{"cited_title":"Non-relativistic torque and Edelstein effect in noncollinear magnets","cited_arxiv_id":"2310.06499","evidence_quote":"Provides the baseline NREE value in LuFeO$_3$ and the 3Q non-coplanar antiferromagnet model used for comparison."},{"cited_title":"Spin-pumping into surface states of topological insulator {\\alpha}-Sn, spin to charge conversion at room temperature","cited_arxiv_id":"1509.02973","evidence_quote":"Supplies the best reported relativistic Rashba Edelstein value (α-Sn films) against which CeNiAsO is compared."},{"cited_title":"Incommensurate magnetism near quantum criticality in CeNiAsO","cited_arxiv_id":"1707.09645","evidence_quote":"Reports the experimental magnetic order of CeNiAsO, the input on which the symmetry and the NREE calculation rest."}],"review_version":1}