{"id":"f2a63453-c481-4e46-941e-91c6df2443f8","arxiv_id":"2505.02769","paper_version":1,"verdict":"REJECT","confidence":"HIGH","novelty_score":4.0,"correctness_risk":"high","formal_verification":"none","parameter_count":3,"one_line_summary":"Mn2PdIn exhibits a sizeable anomalous Hall response that the authors explain by Berry curvature from Weyl-type crossings, but the magnetic glassy state and lack of topological verification weaken the explanation.","lead":"Mn2PdIn, an inverse Heusler alloy, shows a modest anomalous Hall effect even though its magnetic order is a frustrated spin glass with small net moment. The authors link this effect to Weyl-like band crossings and Fermi surface nesting, but the topological claims are not proven.","discovery_kind":"extension","skeptic_critique":{"model":"deepseek-v4-flash","headline":"The transport interpretation rests on a collinear ferrimagnetic DFT state that does not correspond to the measured spin-cluster-glass ground state.","rationale":"The paper contains a substantial set of magnetization, ac-susceptibility, memory, and transport measurements, and the anomalous Hall response is plausibly real. The load-bearing problem is the link between that experiment and the electronic-structure interpretation. The DFT section assumes a collinear FiM order with specified Mn moments, while the measured compound is described as a spin cluster glass with quenched magnetization: the zero-field state lacks the translational magnetic order needed for the computed Bloch bands, Weyl-type crossings, and Berry curvature. The only quantitative link offered, the near equality of the measured low-field saturation moment (0.46 mu_B) and the calculated net moment (0.39 mu_B), does not identify the magnetic structure, especially because M(H) is not saturated and the high-field state is not refined. This is the same weakest assumption the reader identified, and it is sufficient to reject the central claim that the measured AHE is intrinsic and driven by the calculated nesting/topology. A neutron diffraction experiment would settle the correspondence directly. I do not see an independent concern that would alter the verdict in the opposite direction, so the reader's REJECT judgment should stand.","tokens_in":16559,"tokens_out":8902,"duration_ms":111560,"concrete_test":"Measure powder neutron diffraction on Mn2PdIn at 2 K in zero field and under a 7 T field. If no magnetic Bragg peaks appear in zero field, the ground state is a spin glass and the collinear FiM unit cell used in the DFT calculations is not realized, so the computed Weyl crossings and Berry curvature cannot be assigned to the measured sample; if field-induced magnetic Bragg peaks appear, compare their refined magnetic structure (moment magnitudes and directions) with the DFT FiM state before using the calculated AHC to explain the transport.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central claim requires the measured anomalous Hall conductivity to be explained by Berry curvature and Weyl-type crossings computed from a periodic collinear ferrimagnetic (FiM) unit cell with Mn moments +3.75 and -3.48 mu_B (net 0.39 mu_B/f.u.). But the paper's own magnetic characterization (Figs. 2-3) establishes a spin-cluster-glass ground state with quenched magnetization, memory and relaxation behavior, and no long-range magnetic order. The DFT FiM state is therefore not the zero-field state being measured. The high-field state is not established either: M(H) at 2 K continues to increase up to 7 T without saturation, so the field-polarized configuration probed by the Hall measurement is not shown to be the calculated FiM configuration. Because the computed Weyl crossings and the 132 S/cm intrinsic AHC are properties of that assumed ordered state, they cannot be used to interpret the measured sigma_xy ~ 50 S/cm without evidence that the experimental magnetic structure matches the calculation. Even the quadratic rho_A-rho_xx scaling and TYJ decomposition, if accepted, only separate skew scattering from intrinsic/side-jump; they do not supply the missing magnetic-structure correspondence.","agreement_with_reader":"agree"},"referee_report":{"model":"deepseek-v4-flash","summary":"The manuscript reports a combined experimental and DFT study of the inverse Heusler compound Mn2PdIn. Experimental characterization by XRD, TEM, magnetometry, ac susceptibility, and transport shows a spin cluster-glass ground state with quenched magnetization and an anomalous Hall effect (σ_xy ≈ 50 S/cm at 5 K) whose ρ_A versus ρ_xx scaling is quadratic. DFT calculations assume a collinear ferrimagnetic state with opposing Mn moments (net 0.39 μB/f.u.) and yield Weyl-type crossings near E_F, pronounced Fermi-surface nesting, and an intrinsic anomalous Hall conductivity of about 132 S/cm. The paper argues that the measured AHE originates from this topological electronic structure and proposes nesting-induced inter-orbital scattering as a design criterion for AHE-active Heusler compounds.","tokens_in":16787,"tokens_out":6281,"duration_ms":68959,"significance":"If the interpretation were sound, the work would be significant: it would identify a nearly compensated magnetic Heusler system with a robust AHE and propose a concrete electronic-structure design criterion. The experimental data set is fairly complete and internally consistent, and the use of standard TYJ scaling is appropriate as a first step. The DFT calculation is ab initio and not fitted to the measured AHE. However, the central interpretive link is weakened by the mismatch between the magnetic state assumed in the calculation and the state actually characterized in the experiment; the calculated topological properties and AHC cannot be directly assigned to the measured sample without additional evidence. This issue is load-bearing for the paper's main claims.","major_comments":[{"comment":"The DFT calculations assume a collinear ferrimagnetic state with Mn moments +3.75 and −3.48 μB/f.u. (net 0.39 μB/f.u.), whereas the manuscript's own magnetic characterization shows a spin cluster-glass ground state with quenched magnetization, memory and relaxation effects, and frequency-dependent freezing, i.e., no long-range magnetic order. M(H) at 2 K continues to increase up to 7 T without saturation, so the high-field state probed in transport is not shown to be the calculated FiM state. Because the computed Berry curvature, nesting vectors, and intrinsic AHC (132 S/cm) are properties of the ordered collinear state, they cannot be used to interpret the measured σ_xy ≈ 50 S/cm without independent evidence that the experimental magnetic structure matches the calculation.","section":"Magnetometry (Figs. 2–3) and DFT electronic structure"},{"comment":"The crossings near E_F are described as 'strong candidates for Weyl points' and later as 'Weyl-type band crossings,' but no chiral charge, Chern number, or surface-state calculation is presented. The text also states that SOC creates small gaps of 20–50 meV at these crossings, which is incompatible with genuine Weyl points unless a specific symmetry protection is identified. The claim that Mn2PdIn hosts a 'topologically nontrivial electronic structure' is therefore not established by the provided calculations.","section":"Fig. 4 and accompanying text"},{"comment":"The freezing temperature is estimated as 62.3 K using a mean-field formula with a DFT-derived J between FiM and AFM states. Since the experimentally characterized state is a spin cluster glass, not a collinear FiM or AFM state, the relevance of this J is unclear, and the agreement with T_F = 65.5 K cannot be taken as validation of the collinear FiM model. The formula's inputs (J_i,j,avg over 'all possible configurations,' N=8) are not specified in sufficient detail to be reproducible.","section":"Text near the T_F estimate"},{"comment":"The TYJ decomposition into skew-scattering and intrinsic/side-jump contributions uses the spontaneous magnetization M, but the sample is a spin glass with quenched and nonsaturating magnetization, making the appropriate M ill-defined. The resulting coefficients (a ≈ −0.062, b ≈ 63 S/cm) therefore do not robustly support the claim that the intrinsic Berry-curvature mechanism dominates the measured AHE.","section":"Fig. 5(f) and TYJ scaling"}],"minor_comments":[{"comment":"The title 'Fiting parameters' should read 'Fitting parameters.'","section":"Table II title"},{"comment":"The text contains a typo: 'Slatter-Puling rule' should be 'Slater-Pauling rule.'","section":"Equations and text (magnetization section)"},{"comment":"The phrase 'octagonally coordinated' should be 'octahedrally coordinated.'","section":"Structural description (Fig. 1 inset and text)"},{"comment":"The relaxation formula M(t)=M0(1+a exp[−(t/τ)^β]) appears to have the wrong sign convention for a zero-field-cooled relaxation; a standard KWW form is M(t)=M0[1−exp(−(t/τ)^β)] over a suitable baseline, and the present form should be checked.","section":"Relaxation equation (Fig. 2(c) text)"},{"comment":"The phrase 'yield numerically equivalent results 82.82' contains a duplicated reference marker; it should be 'results [82]' or similar.","section":"AHC calculation text"}],"recommendation":"reject","confidential_remarks":"The experimental transport and magnetometry data appear internally consistent, but the theoretical interpretation is anchored to a collinear ferrimagnetic state that the authors' own magnetic characterization shows is not realized in zero field. Establishing the connection between the calculated Berry curvature and the measured AHE would require new magnetic structure determination (e.g., neutron diffraction) and recalculation for a noncollinear or disordered state, which is beyond the scope of a revision. The paper also overstates the Weyl character without computing topological invariants."},"author_rebuttal":null,"desk_editor":{"model":"deepseek-v4-flash","letter":"Colleague,\n\nQuick take: this is a solid, well-executed experimental study of a previously uncharacterized inverse Heusler compound, and the anomalous Hall effect in Mn2PdIn is probably real. What is new: the first AHE data for Mn2PdIn, plus a DFT band structure and an intrinsic AHC estimate. The synthesis and characterization are careful; the cluster-glass ground state is convincingly established through DC/AC susceptibility, relaxation, and memory effects. The Hall measurements are standard and the AHE extraction is internally consistent.\n\nThe soft spot is the interpretation. The paper claims the AHE is intrinsic, driven by Berry curvature from Weyl-type crossings and Fermi surface nesting. But the DFT assumes a collinear ferrimagnetic state with Mn moments +3.75 and -3.48 μB, while the zero-field ground state is a spin cluster glass with no long-range order. The high-field state is not shown to be the collinear FiM state either; M(H) at 2 K keeps rising to 7 T. So the calculated Weyl crossings and 132 S/cm intrinsic AHC are properties of an ordered state that is not the state being measured. The quadratic ρ_A-ρ_xx scaling and TYJ decomposition do not fix this gap; they only constrain the scattering mechanisms within a ferromagnetic-like picture. Also, the 'Weyl-type' claim is never backed by a topological analysis—no chiral charge, no surface states, just crossings in a band plot.\n\nThere are some minor issues too: the nesting argument is qualitative, and the TYJ scaling is applied to a spin-glass system, where the standard assumptions are weaker. That said, the authors honestly report the mismatch between calculated and measured AHC (132 vs ~50 S/cm), so the paper is not hiding the problem.\n\nWho is this for: materials scientists working on Heusler AHE or magnetic topological metals. The data are worth having, but the central claim as stated is not proven. I would send it to peer review with a request for major revision: either provide a topological characterization of the crossings, or substantially soften the intrinsic/Weyl interpretation to match the disordered magnetic state.\n\nWould I cite it? Probably yes, for the AHE data on Mn2PdIn.\n\nBest,","headline":"Solid experimental study of a new AHE material, but the Berry-curvature/Weyl interpretation rests on a collinear magnetic state that the paper's own data say is not the ground state.","tokens_in":17343,"tokens_out":2203,"would_cite":true,"duration_ms":24521,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":[],"model":"deepseek-v4-flash","headline":"The paper establishes that the inverse Heusler alloy Mn2PdIn, despite a spin-glassy nearly compensated magnetic state, hosts Weyl-type band crossings and an intrinsic anomalous Hall effect driven by Berry curvature and Fermi surface…","keywords":["Mn2PdIn","inverse Heusler alloy","anomalous Hall effect","Berry curvature","Fermi surface nesting","spin cluster glass","Weyl semimetal","magnetotransport"],"falsifier":"A neutron diffraction or muon-spin rotation experiment below the freezing temperature could settle it: if it finds no collinear ferrimagnetic order with manganese moments near $\\pm 3.5\\,\\mu_B$, the computed Weyl crossings, nesting vector, and Berry curvature cannot be the mechanism producing the measured anomalous Hall effect.","tokens_in":16348,"feed_emoji":"🧲","tokens_out":12484,"duration_ms":129449,"temperature":0.7,"pith_summary":"Mn2PdIn is an inverse Heusler alloy (a cubic intermetallic with four interpenetrating fcc sublattices) whose manganese moments almost cancel, leaving a net magnetization near zero. The paper argues that, despite freezing into a spin cluster glass (a frozen state of disordered magnetic clusters), this compound has a topologically nontrivial electronic structure: Weyl-type band crossings sit near the Fermi level and the Fermi surface contains nested, near-parallel pockets. The measured anomalous Hall effect is then intrinsic, coming from Berry curvature rather than from impurity skew scattering; the key evidence is that the anomalous Hall resistivity scales quadratically with the longitudinal resistivity and the anomalous Hall conductivity is nearly temperature independent. If this is right, Mn2PdIn offers a route to low-moment, frustration-prone magnets that still give clear transverse transport signals, which matters for spintronics.","feed_headline":"Spin-glass Mn2PdIn shows intrinsic anomalous Hall effect","feed_subtitle":"Hall resistivity grows as resistivity squared, the signature of a Berry-curvature effect from nested Fermi surfaces.","key_machinery":"The load-bearing object is the nesting geometry of the Fermi surface in a time-reversal-broken, spin-orbit-coupled metal. A nesting vector $q_{\\rm nest}\\sim\\Gamma\\to X$ connects dispersive Mn $e_g$ electron-like pockets at $\\Gamma$ with quasi-flat, hybridized Mn $t_{2g}$-Pd $t_{2g}$ hole-like pockets near $X$; the near-parallel contours and the orbital contrast between them enhance interband scattering, while spin-orbit coupling opens small gaps of order 20-50 meV at the band crossings and turns those crossings into sources and sinks of Berry curvature. The linear-response formalism then integrates this Berry curvature over the Brillouin zone to obtain an intrinsic anomalous Hall conductivity, and the quadratic relation $\\rho^A_{xy}\\propto\\rho_{xx}^2$ together with a temperature-independent $\\sigma^A_{xy}$ is used as the experimental fingerprint of that intrinsic mechanism.","core_discovery":"The central claim is that Mn2PdIn is a topologically nontrivial metal whose anomalous Hall effect is intrinsic. In the paper's picture, the inverse Heusler structure hosts two inequivalent manganese sublattices with opposing moments ($+3.75$ and $-3.48\\,\\mu_B$ from first-principles calculations; net $0.39\\,\\mu_B$ per formula unit, against $0.46\\,\\mu_B$ from magnetization data), leaving a nearly compensated ferrimagnet that freezes into a spin cluster glass below about 65.5 K. First-principles electronic-structure calculations with spin-orbit coupling find Weyl-type band crossings close to the Fermi level and a Fermi surface with an electron-like Mn $e_g$ pocket at $\\Gamma$ nested against hole-like Mn $t_{2g}$/Pd $t_{2g}$ pockets near $X$ through a nesting vector $q_{\\rm nest}\\sim\\Gamma\\to X$. Linear-response integration of the Berry curvature gives an intrinsic anomalous Hall conductivity of about 132 S cm$^{-1}$ at the Fermi level, rising to roughly 937-1003 S cm$^{-1}$ when the chemical potential is shifted by $-2.1$ or $+0.8$ eV. Experimentally, the anomalous Hall resistivity obeys $\\rho^A_{xy}\\propto\\rho_{xx}^2$, the anomalous Hall conductivity is about 50 S cm$^{-1}$ and nearly temperature independent, and scaling analysis places skew scattering as a minor contributor; the paper reads these as confirmation that the anomalous Hall effect is dominated by the intrinsic Berry-curvature/nesting mechanism.","pith_inferences":["Going beyond the paper, if the true magnetic ground state is a noncollinear cluster glass rather than the collinear ferrimagnet assumed in the calculations, the measured Hall effect might instead arise from local noncollinear spin textures or disorder-modified bands; neutron scattering would decide between these.","Going beyond the paper, the predicted sharp rise of the anomalous Hall conductivity when the chemical potential shifts by $-2.1$ or $+0.8$ eV makes doping a direct test: substituting a neighboring element to move $E_F$ should either produce a much larger anomalous Hall effect or rule out the band-structure mechanism.","Going beyond the paper, the nesting criterion itself is transferable: screening isostructural Mn$_2$Pd-based and related Heusler compounds for parallel Fermi contours with contrasting orbital character could identify other anomalous-Hall-active magnets.","Going beyond the paper, angle-resolved photoemission on a single crystal could directly test the calculated flat Mn $e_g$/Pd $t_{2g}$ bands and the Weyl-type crossings near the Fermi level."],"forward_implications":["Mn2PdIn becomes a concrete example of an inverse Heusler alloy with suppressed net magnetization and an intrinsic anomalous Hall response, relevant for spintronic applications.","The Fermi-surface nesting criterion (nested electron- and hole-like pockets with orbital contrast in a spin-orbit-coupled magnet) can be used to screen other Heusler and related intermetallics for anomalous Hall activity.","Because the computed anomalous Hall conductivity rises strongly when the chemical potential shifts away from the Fermi level, doping or strain that moves $E_F$ should produce a much larger intrinsic anomalous Hall effect than measured in the stoichiometric compound.","The quadratic $\\rho^A_{xy}$-$\\rho_{xx}$ scaling, together with the scaling analysis, implies that skew scattering is not the origin of the anomalous Hall effect; intrinsic and side-jump contributions dominate even in a spin-glass host."],"supporting_citations":[{"why":"Earlier report of the synthesis, structure, and magnetic properties of Mn2PdIn; it provides the baseline sample behavior this work extends.","marker":"[27]"},{"why":"The isostructural Mn2PdSn magnetic Weyl metal whose anomalous Hall response motivates looking for Weyl-type crossings in Mn2PdIn.","marker":"[18]"},{"why":"Supplies the first-principles linear-response method used to compute the intrinsic anomalous Hall conductivity.","marker":"[79]"},{"why":"Supplies the dense k-mesh and extrapolation protocol used to converge the computed anomalous Hall conductivity.","marker":"[80]"},{"why":"Gives anomalous Hall conductivities of Co-based Heusler compounds used as comparison benchmarks for the calculated magnitude.","marker":"[81]"},{"why":"Establishes the Berry-curvature picture of the anomalous Hall effect in Heusler compounds, the theoretical frame for the claim.","marker":"[83]"},{"why":"Provides the scaling relation used to separate skew scattering from the intrinsic contribution in the transport data.","marker":"[52]"},{"why":"Supplies the standard scaling and mechanism analysis used to identify the anomalous Hall effect as intrinsic.","marker":"[53]"},{"why":"Characterizes the parent Mn3In spin glass and shows the absence of an anomalous Hall effect there, the contrast that sets up the Mn2PdIn claim.","marker":"[25]"}],"fun_headline_variants":["Intrinsic anomalous Hall effect from Fermi nesting in Mn2PdIn","Fermi surface nesting yields Berry-curvature Hall effect","Spin-glass Mn2PdIn shows topological Hall effect","Berry curvature drives Hall effect in frustrated Mn2PdIn"],"cache_read_input_tokens":3200,"weakest_assumption_plain":"The calculations assume a collinear ferrimagnetic arrangement of the manganese moments with values near $+3.75$ and $-3.48\\,\\mu_B$, whereas the measured sample is a spin cluster glass with no confirmed long-range magnetic order; if the true magnetic structure differs, the predicted Weyl crossings, nesting vector, and Berry curvature need not describe the measured Hall effect.","fun_headline_variants_meta":{"raw":{"variants":["Intrinsic anomalous Hall effect from Fermi nesting in Mn2PdIn","Fermi surface nesting yields Berry-curvature Hall effect","Spin-glass Mn2PdIn shows topological Hall effect","Berry curvature drives Hall effect in frustrated Mn2PdIn"]},"model":"deepseek-v4-flash","effort":"low","cost_usd":0.000787,"raw_usage":{"total_tokens":3529,"prompt_tokens":1060,"completion_tokens":2469,"prompt_tokens_details":{"cached_tokens":384},"prompt_cache_hit_tokens":384,"prompt_cache_miss_tokens":676,"completion_tokens_details":{"reasoning_tokens":2400}},"tokens_in":676,"tokens_out":2469,"duration_ms":20507,"temperature":1.0,"reasoning_tokens":2400,"cache_read_input_tokens":384,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-08-16T00:41:28.924782+00:00","model_set":{"reader":"deepseek-v4-flash"},"falsifier":"A neutron diffraction or muon-spin rotation experiment below the freezing temperature could settle it: if it finds no collinear ferrimagnetic order with manganese moments near $\\pm 3.5\\,\\mu_B$, the computed Weyl crossings, nesting vector, and Berry curvature cannot be the mechanism producing the measured anomalous Hall effect.","supporting_citations":[{"cited_title":"Huang et al., Anomalous Hall effect and current spin polarization in Co2FeX Heusler compounds (X = Al, Ga, In, Si, Ge, and Sn): A systematic ab initio study, Phys","cited_arxiv_id":null,"evidence_quote":"Gives anomalous Hall conductivities of Co-based Heusler compounds used as comparison benchmarks for the calculated magnitude."},{"cited_title":null,"cited_arxiv_id":null,"evidence_quote":"Earlier report of the synthesis, structure, and magnetic properties of Mn2PdIn; it provides the baseline sample behavior this work extends."},{"cited_title":"Bhattacharya, M","cited_arxiv_id":null,"evidence_quote":"The isostructural Mn2PdSn magnetic Weyl metal whose anomalous Hall response motivates looking for Weyl-type crossings in Mn2PdIn."},{"cited_title":null,"cited_arxiv_id":null,"evidence_quote":"Supplies the first-principles linear-response method used to compute the intrinsic anomalous Hall conductivity."},{"cited_title":"Fuh and G.-Y","cited_arxiv_id":null,"evidence_quote":"Supplies the dense k-mesh and extrapolation protocol used to converge the computed anomalous Hall conductivity."},{"cited_title":"K\\\"ubler, and C","cited_arxiv_id":null,"evidence_quote":"Establishes the Berry-curvature picture of the anomalous Hall effect in Heusler compounds, the theoretical frame for the claim."},{"cited_title":"Nagaosa, J","cited_arxiv_id":null,"evidence_quote":"Supplies the standard scaling and mechanism analysis used to identify the anomalous Hall effect as intrinsic."},{"cited_title":"Chatterjee, P","cited_arxiv_id":null,"evidence_quote":"Characterizes the parent Mn3In spin glass and shows the absence of an anomalous Hall effect there, the contrast that sets up the Mn2PdIn claim."}],"review_version":1}