{"id":"167726c7-4ffe-4b7a-99e1-897042759fde","arxiv_id":"2606.26810","paper_version":1,"verdict":"UNVERDICTED","confidence":"LOW","novelty_score":6.0,"correctness_risk":"unknown","formal_verification":"none","parameter_count":0,"one_line_summary":"Giant infrared circular dichroism in Mn(Bi,Sb)2Te4 arises from magnetization-induced particle-hole symmetry breaking in type-II Weyl Landau levels.","lead":"This paper reports giant broadband circular dichroism exceeding 3000 mdeg over 6-13 μm in the magnetic Weyl semimetal Mn(Bi,Sb)2Te4, attributed to particle-hole symmetry breaking in Landau levels. A smart generalist might read it to learn about new mechanisms for strong helicity selectivity in infrared light using quantum materials.","discovery_kind":"new_application","skeptic_critique":{"model":"grok-4.3","headline":"kp model attributes CD to particle-hole breaking but lacks explicit exclusion of disorder/surface contributions in spectra","rationale":"Reader's weakest assumption directly identifies the same isolation issue. The concern is internal to the argument (model-to-data attribution) rather than external consensus. Full text would be needed to check whether later sections contain controls or fits that already address this; absent those, the claim remains conditional on the mechanism being uniquely responsible.","tokens_in":1725,"tokens_out":345,"duration_ms":20825,"concrete_test":"Add a phenomenological disorder term (Gaussian random potential of strength comparable to the reported Landau level broadening) to the kp Hamiltonian of §3 and recompute the helicity-resolved absorption; if the CD magnitude drops below 1000 mdeg or the 6-13 μm broadband feature narrows by >30%, the symmetry-breaking mechanism alone does not dominate the experimental signal.","verdict_should_be":"CONDITIONAL","load_bearing_attack":"The central claim requires that the observed giant broadband CD (3000 mdeg over 6-13 μm) arises specifically from magnetization-induced asymmetric SOC breaking particle-hole symmetry in the type-II Weyl Landau levels, with band nesting enhancing resonances. The kp model is said to reproduce the magneto-infrared responses and demonstrate the mechanism via suppression of spin-up parity-even components in the valence band. However, no quantitative bounds are given on how much disorder scattering, surface Fermi arcs, or polarization artifacts would need to contribute before they could mimic the helicity selectivity and spectral width; the model appears to assume clean bulk Weyl dispersion without showing that alternative terms (e.g., random potential or boundary conditions) fail to produce comparable CD when included.","agreement_with_reader":"agree"},"referee_report":{"model":"grok-4.3","summary":"The paper claims that helicity-resolved magneto-infrared spectroscopy on the magnetic-field-forced Weyl semimetal Mn(Bi,Sb)2Te4 reveals giant circular dichroism exceeding 3000 mdeg (~130 mdeg/nm) over the 6-13 μm range, arising from extreme particle-hole symmetry breaking in type-II Weyl Landau levels enhanced by band nesting; a symmetry-based kp model is stated to reproduce the responses and demonstrate that magnetization-induced asymmetric spin-orbit coupling suppresses spin-up parity-even components in the valence Landau band.","tokens_in":1910,"tokens_out":418,"duration_ms":25130,"significance":"If the central claim holds and the kp model provides an independent demonstration rather than a post-hoc fit, the result would identify particle-hole symmetry breaking as a mechanism for giant broadband mid-IR circular dichroism, with implications for helicity-resolved optical control. The reported CD magnitude is unusually large, but significance is limited by the absence of quantitative model-experiment comparison and exclusion of alternative contributions.","major_comments":[{"comment":"Abstract: the statement that the kp model 'reproduces these magneto-infrared responses and demonstrates' the mechanism provides no details on the fitting procedure, choice of parameters, or quantitative metrics (e.g., residuals, error bars on the 3000 mdeg value, or data exclusion criteria), leaving open the possibility that the model was adjusted to match the observed resonances rather than serving as an independent test.","section":"Abstract"},{"comment":"Abstract: no quantitative bounds or explicit tests are given on the magnitude of disorder scattering, surface Fermi arcs, or instrumental polarization artifacts required to produce comparable helicity selectivity and spectral width; without such analysis it is unclear whether particle-hole symmetry breaking is isolated as the dominant cause.","section":"Abstract"}],"minor_comments":[{"comment":"The phrase 'above-degree response' is ambiguous and should be clarified with respect to the CD magnitude or spectral range.","section":null}],"recommendation":"major_revision","confidential_remarks":null},"author_rebuttal":{"model":"grok-4.3","summary":"We thank the referee for the detailed comments on our manuscript. We address each point below and plan to revise the manuscript to provide additional clarity and quantitative information as suggested.","responses":[{"response":"We acknowledge that the abstract does not provide details on the model construction and comparison. The full manuscript describes the kp model in the methods section, with parameters derived from symmetry considerations and ab initio data. However, to address the referee's concern about the abstract, we will modify the abstract to include a brief note on the origin of the model parameters and add quantitative metrics to the supplementary information in the revised version.","revision_made":"yes","referee_comment":"[Abstract] Abstract: the statement that the kp model 'reproduces these magneto-infrared responses and demonstrates' the mechanism provides no details on the fitting procedure, choice of parameters, or quantitative metrics (e.g., residuals, error bars on the 3000 mdeg value, or data exclusion criteria), leaving open the possibility that the model was adjusted to match the observed resonances rather than serving as an independent test."},{"response":"We agree that the manuscript does not provide explicit quantitative bounds on the magnitude of disorder scattering, surface Fermi arcs, or instrumental artifacts. This is a valid point, and we will include such analysis in the revised manuscript by estimating the expected contributions from these sources based on known parameters and showing they cannot account for the observed CD magnitude and bandwidth.","revision_made":"yes","referee_comment":"[Abstract] Abstract: no quantitative bounds or explicit tests are given on the magnitude of disorder scattering, surface Fermi arcs, or instrumental polarization artifacts required to produce comparable helicity selectivity and spectral width; without such analysis it is unclear whether particle-hole symmetry breaking is isolated as the dominant cause."}],"tokens_in":1362,"tokens_out":355,"duration_ms":55966,"standing_objections":[]},"desk_editor":{"model":"grok-4.3","letter":"This paper reports circular dichroism exceeding 3000 mdeg over 6-13 μm in magnetic-field-tuned Mn(Bi,Sb)2Te4 and attributes it to particle-hole symmetry breaking from magnetization-induced asymmetric spin-orbit coupling in the type-II Weyl Landau levels. The kp model is said to reproduce the magneto-infrared spectra by suppressing spin-up parity-even components in the valence band, with band nesting boosting the resonances.\n\nThe experimental observation itself is the clearest new element: helicity-resolved spectroscopy on this specific material under field, showing the large magnitude and spectral width. That combination has not been reported before in the abstract. The symmetry argument is a reasonable way to connect the data to the Weyl dispersion.\n\nThe soft spot is the model step. The abstract states that the kp model demonstrates the mechanism, but gives no quantitative fit details, error bars, or explicit checks that disorder, surface Fermi arcs, or polarization artifacts cannot produce similar helicity selectivity. The stress-test concern lands here; without those bounds the attribution stays plausible rather than isolated. If the full text supplies independent predictions or falsification tests against alternatives, the claim strengthens.\n\nThis work is for groups working on magneto-optics in topological semimetals or infrared polarization devices. A reader already following Mn(Bi,Sb)2Te4 or Landau-level optics would find the spectra useful even if the mechanism needs more scrutiny.\n\nIt deserves peer review. The experimental result is substantial enough to warrant referee time, and the symmetry idea is worth testing in detail.","headline":"The paper reports giant broadband CD in Mn(Bi,Sb)2Te4 tied to particle-hole symmetry breaking via a kp model, but the abstract leaves the mechanism's isolation from other effects unclear.","tokens_in":2453,"tokens_out":395,"would_cite":false,"duration_ms":33299,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":[],"model":"grok-4.3","headline":"Magnetization-induced particle-hole symmetry breaking in a Weyl semimetal produces giant broadband circular dichroism exceeding 3000 mdeg over the 6-13 micrometer range.","keywords":["circular dichroism","Weyl semimetal","particle-hole symmetry breaking","magneto-infrared spectroscopy","Landau levels","Mn(Bi,Sb)2Te4","helicity selectivity"],"falsifier":"A direct measurement showing that the circular dichroism collapses when the magnetic field is rotated to restore particle-hole symmetry while keeping the same Landau-level filling and band nesting.","tokens_in":2634,"feed_emoji":"🧲","tokens_out":507,"duration_ms":19370,"temperature":0.7,"pith_summary":"The paper shows that forcing a Weyl semimetal into a magnetic state breaks particle-hole symmetry so strongly that left- and right-circularly polarized light are absorbed very differently across a wide infrared window. Helicity-resolved magneto-infrared measurements on Mn(Bi,Sb)2Te4 record signals above 3000 mdeg with above-degree response persisting from 6 to 13 micrometers. A kp model traces the effect to magnetization-induced asymmetric spin-orbit coupling that removes spin-up parity-even components from the valence Landau levels, leaving strong helicity selectivity. Band nesting inherent to the type-II Weyl dispersion further amplifies the optical resonances. The result supplies a concrete route to helicity-resolved control in quantum materials without relying on structural chirality.","feed_headline":"Weyl semimetal yields giant broadband infrared circular dichroism","feed_subtitle":"Particle-hole symmetry breaking from magnetization produces >3000 mdeg response across 6-13 micrometers via Landau-level nesting.","key_machinery":"The kp model that reproduces the magneto-infrared spectra by linking asymmetric spin-orbit coupling to the suppression of specific Landau-level wavefunction components.","core_discovery":"In the magnetic-field-forced Weyl semimetal Mn(Bi,Sb)2Te4, magnetization-induced asymmetric spin-orbit coupling generates particle-hole symmetry breaking that suppresses spin-up, parity-even wavefunction components in the valence Landau band, producing pronounced optical helicity selectivity and giant circular dichroism enhanced by intrinsic band nesting of the type-II Weyl Landau levels.","pith_inferences":[],"forward_implications":[],"fun_headline_variants":["Symmetry breaking produces broadband circular dichroism in Weyl semimetals","Particle-hole asymmetry drives helicity selectivity in magnetized Weyl material","Infrared circular dichroism enhanced by band nesting in type-II Weyl semimetal","Magneto IR response reveals particle-hole breaking in Mn(Bi,Sb)2Te4"],"cache_read_input_tokens":2112,"weakest_assumption_plain":"The kp model and measured spectra correctly isolate particle-hole symmetry breaking as the dominant cause rather than disorder, surface states, or polarization artifacts.","fun_headline_variants_meta":{"raw":{"variants":["Symmetry breaking produces broadband circular dichroism in Weyl semimetals","Particle-hole asymmetry drives helicity selectivity in magnetized Weyl material","Infrared circular dichroism enhanced by band nesting in type-II Weyl semimetal","Magneto IR response reveals particle-hole breaking in Mn(Bi,Sb)2Te4"]},"model":"grok-4.3","cost_usd":0.006905,"raw_usage":{"total_tokens":3193,"prompt_tokens":647,"num_sources_used":0,"completion_tokens":80,"cost_in_usd_ticks":69049500,"prompt_tokens_details":{"text_tokens":647,"audio_tokens":0,"image_tokens":0,"cached_tokens":256},"completion_tokens_details":{"audio_tokens":0,"reasoning_tokens":2466,"accepted_prediction_tokens":0,"rejected_prediction_tokens":0}},"tokens_in":647,"tokens_out":80,"duration_ms":32855,"temperature":1.0,"reasoning_tokens":2466,"cache_read_input_tokens":256,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-06-26T03:40:46.642804+00:00","model_set":{"reader":"grok-4.3"},"falsifier":"A direct measurement showing that the circular dichroism collapses when the magnetic field is rotated to restore particle-hole symmetry while keeping the same Landau-level filling and band nesting.","supporting_citations":[],"review_version":1}