Magnetothermopower and particle-hole symmetry in a cuprate strange metal

Jake Ayres; Matija \v{C}ulo; Mikhail I. Katsnelson; Mikhail Titov; Nigel E. Hussey; Steffen Wiedmann; Thom Ottenbros; Yingkai Huang; Yu-Te Hsu

Overdoped cuprate strange metals host two transport sectors with opposite particle-hole symmetry, one a conventional Fermi liquid and one a nearly particle-hole-symmetric Dirac liquid of phase-incoherent superconducting quasiparticles.

Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →

Challenge this review Re-run · record.json Download PDF Read on arXiv ↗

T0 review · grok-4.5

2026-07-15 06:03 UTC pith:RYLHAPQ6

load-bearing objection New high-field magnetothermopower on overdoped Bi2201 plus a clear two-sector particle-hole picture; the SC-fluctuation assignment for the extra S(H) is still only consistency, not exclusion. the 3 major comments →

arxiv 2607.12442 v1 pith:RYLHAPQ6 submitted 2026-07-14 cond-mat.supr-con cond-mat.str-el

Magnetothermopower and particle-hole symmetry in a cuprate strange metal

Yu-Te Hsu , Matija \v{C}ulo , Thom Ottenbros , Yingkai Huang , Jake Ayres , Steffen Wiedmann , Mikhail I. Katsnelson , Nigel E. Hussey

show 1 more author

Mikhail Titov

This is my paper

classification cond-mat.supr-con cond-mat.str-el

keywords magnetothermopowercuprate strange metalparticle-hole symmetryoverdoped Bi2201Fermi liquidphase-incoherent superconductivityBogoliubov quasiparticlesmagnetotransport

verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

This paper reports magnetothermopower measurements on overdoped Bi2201 cuprate crystals in fields up to 35 T and argues that the field-dependent Seebeck response cannot be explained by ordinary Boltzmann transport. While the zero-field Seebeck coefficient follows Fermi-liquid expectations, the magnetothermopower contains a large extra contribution whose field and temperature dependence matches short-range superconducting order well above Tc. Together with earlier Hall and magnetoresistance data, the authors conclude that the overdoped strange metal contains two coexisting transport sectors: a conventional particle-hole-asymmetric Fermi liquid that governs the Hall effect and zero-field thermopower, and a nearly particle-hole-symmetric sector that dominates the anomalous longitudinal magnetotransport. They propose a real-space picture in which disconnected Fermi-liquid islands sit inside a compensated Dirac liquid of phase-incoherent d-wave Bogoliubov quasiparticles. If correct, the picture supplies a concrete way to reconcile ordinary zero-field transport with the anomalous field-dependent response that defines strange metallicity in overdoped cuprates.

Core claim

The overdoped cuprate strange metal contains two transport sectors of distinct particle-hole symmetry: a conventional particle-hole-asymmetric Fermi-liquid contribution that sets the Hall effect and zero-field thermopower, and a nearly particle-hole-symmetric sector—identified as a compensated Dirac liquid of phase-incoherent d-wave Bogoliubov quasiparticles from short-range superconducting order well above Tc—that dominates the large field-dependent magnetothermopower and other anomalous longitudinal magnetotransport.

What carries the argument

A phenomenological real-space two-sector model in which disconnected Fermi-liquid islands are embedded in a compensated Dirac liquid of phase-incoherent d-wave Bogoliubov quasiparticles; the second sector supplies the nearly particle-hole-symmetric channel that produces the extra magnetothermopower Boltzmann theory cannot capture.

Load-bearing premise

That the large extra magnetothermopower contribution is caused by a nearly particle-hole-symmetric liquid of phase-incoherent superconducting quasiparticles rather than by some other field-dependent mechanism such as orbital magnetoresistance or density-wave fluctuations.

What would settle it

A high-field magnetothermopower measurement that either eliminates the additional contribution while short-range superconducting correlations remain, or shows that the same extra term appears in a non-superconducting control system with comparable Fermi-liquid parameters.

Watch this falsifier — get emailed when new claim-graph text bears on it.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit.

Desk Editor's Note

New high-field magnetothermopower on overdoped Bi2201 plus a clear two-sector particle-hole picture; the SC-fluctuation assignment for the extra S(H) is still only consistency, not exclusion.

read the letter

The one thing worth knowing is that they have a new high-field magnetothermopower dataset on overdoped Bi2201 (to 35 T) and they use it to push a concrete two-sector real-space picture: particle-hole-asymmetric FL islands that set Hall and zero-field S, plus a nearly particle-hole-symmetric sector that dominates the anomalous longitudinal magnetotransport. That framing is useful even if you only read the abstract.

What is actually new is the S(H) data themselves and the explicit construction—disconnected FL islands embedded in a compensated Dirac liquid of phase-incoherent d-wave Bogoliubov quasiparticles. They give credit to earlier Hall and MR work and do not pretend the thermopower alone invents the two-sector idea. Zero-field S(T) being Boltzmann-like while S(H) is not is a clean experimental contrast, and particle-hole symmetry is the right language for why thermopower and Hall can look conventional while longitudinal magnetotransport does not.

The soft spot is exactly where the stress-test puts it, and it is load-bearing but not fatal. The abstract only says the extra field- and temperature-dependent piece is “consistent with” short-range SC order well above Tc. Without the full text we cannot see the quantitative Boltzmann baseline, the size of the residual, or any attempt to rule out orbital MR, density-wave fluctuations, or multiband effects. If another mechanism produces that residual, the claim of two distinct particle-hole-symmetry sectors weakens. That is an interpretive step, not a derivation, and it should be treated as such. Circularity is low: the work is primarily experimental plus a phenomenological model, not a self-referential fit.

This is for people who already care about overdoped cuprate transport and strange-metal phenomenology. A serious referee should see the full figures and methods; the dataset and the organizing picture are both worth that time. I would not desk-reject it. Bring it to reading group only after the full text is out, and cite the data once they are public; the model is a useful organizing hypothesis, not yet a settled mechanism.

Referee Report

3 major / 2 minor

Summary. The manuscript reports high-field magnetothermopower measurements (up to 35 T) on overdoped Bi2201 single crystals. It asserts that the zero-field Seebeck coefficient S(T) is captured by Boltzmann transport theory, whereas the field-dependent response S(H) is not: a large additional contribution appears whose field and temperature dependence is said to be consistent with short-range superconducting order well above Tc. Combining these data with earlier Hall and magnetoresistance results, the authors propose that the overdoped cuprate strange metal comprises two transport sectors of distinct particle-hole symmetry—a conventional particle-hole-asymmetric Fermi-liquid sector that governs Hall and zero-field thermopower, and a nearly particle-hole-symmetric sector that dominates anomalous longitudinal magnetotransport. They formulate a phenomenological real-space picture of disconnected FL islands embedded in a compensated Dirac liquid of phase-incoherent d-wave Bogoliubov quasiparticles.

Significance. If the two-sector interpretation is quantitatively supported by the data, the work would supply a concrete, multi-probe constraint on strange metallicity in overdoped cuprates and a falsifiable real-space framework that reconciles conventional zero-field transport with anomalous magnetothermopower and magnetoresistance. High-field thermopower is a valuable complementary probe of particle-hole symmetry, and the explicit link to prior Hall/MR results strengthens the multi-experiment case. The phenomenological model is in principle testable against field, temperature, and doping dependence.

major comments (3)

[Abstract (central claim)] The load-bearing interpretive step—from the statement that S(H) cannot be captured by Boltzmann transport to the identification of a nearly particle-hole-symmetric sector of phase-incoherent d-wave Bogoliubov quasiparticles from short-range SC order well above Tc—is only asserted as ‘consistent with’ in the abstract. Without a quantitative residual S(H) after subtraction of a documented Boltzmann baseline, explicit comparison of its H and T dependence to model predictions, and systematic exclusion or bounding of alternative field-dependent mechanisms (orbital magnetoresistance, density-wave fluctuations, multiband effects not in the baseline), the two-sector claim remains unsecured. This step is central: if another mechanism accounts for the extra magnetothermopower, the distinct particle-hole-symmetry sectors collapse.
[Abstract (zero-field S(T) claim)] The claim that zero-field S(T) ‘can be captured using Boltzmann transport theory’ is foundational for isolating the anomalous field-dependent piece. The manuscript must show the actual Boltzmann calculation (band parameters, scattering assumptions, fit quality or residual), not merely assert capture. Absent that comparison, the residual attributed to the second sector cannot be defined.
[Abstract (phenomenological model)] The phenomenological real-space model (disconnected FL islands in a compensated Dirac liquid of phase-incoherent d-wave Bogoliubov quasiparticles) is offered as the unifying picture. It must be shown to account for the magnitude as well as the qualitative H/T dependence of the additional magnetothermopower, and to remain consistent with the Hall response being FL-dominated. A purely qualitative ‘consistency’ statement is insufficient for a load-bearing model of this type.

minor comments (2)

Only the abstract was available for this review. Figure panels, error bars, sample characterization (Tc, doping), raw S(H,T) data, and the explicit Boltzmann baselines are essential for any final assessment and should be checked carefully once the full text is in hand.
Notation for the two sectors and for the residual magnetothermopower (e.g., ΔS(H) after Boltzmann subtraction) should be introduced early and used consistently so that the separation of contributions is unambiguous.

Circularity Check

0 steps flagged

No significant circularity: abstract-only experimental report with phenomenological interpretation; no derivation that reduces by construction to fitted inputs or self-definition.

full rationale

Only the abstract is available. It reports magnetothermopower data on overdoped Bi2201, notes that zero-field S(T) is capturable by Boltzmann transport while S(H) is not, and states that the additional field-dependent contribution is 'consistent with' short-range superconducting order well above Tc. Combined with earlier Hall and magnetoresistance results, this motivates a two-sector phenomenological real-space model (FL islands in a compensated Dirac liquid of phase-incoherent d-wave Bogoliubov quasiparticles). There are no equations, no fitted parameters renamed as predictions, no uniqueness theorems, and no self-definitional loops in the provided text. The interpretive step from 'cannot be captured by Boltzmann' to the SC-fluctuation picture is a scientific hypothesis, not a circular reduction of output to input by construction. Self-citation of prior Hall/MR work is normal supporting context and is not load-bearing for a claimed first-principles derivation. Per the hard rules, an abstract-only experimental/phenomenological paper with no exhibited reduction scores 0; residual concerns about alternative mechanisms or shared samples belong to correctness risk, not circularity.

Axiom & Free-Parameter Ledger

0 free parameters · 4 axioms · 1 invented entities

Abstract-only audit. No numerical free parameters are stated. The claim rests on standard transport theory plus domain assumptions about cuprate pairing and on a phenomenological real-space construction introduced to reconcile the data. The invented two-sector entities are the main theoretical addition; they lack independent evidence outside the transport anomalies they are built to explain.

axioms (4)

domain assumption Zero-field Seebeck coefficient of overdoped Bi2201 is adequately described by Boltzmann transport on a conventional Fermi surface.
Stated as fact in the abstract; underpins the claim that only the field-dependent piece is anomalous.
domain assumption Short-range superconducting order (phase-incoherent d-wave pairing) can persist well above bulk Tc and produce a nearly particle-hole-symmetric transport sector.
Central interpretive premise linking the extra magnetothermopower to Bogoliubov quasiparticles; contested in the cuprate literature and not derived here.
ad hoc to paper A compensated Dirac liquid of Bogoliubov quasiparticles is nearly particle-hole symmetric and therefore contributes weakly to Hall and zero-field thermopower while dominating longitudinal magnetotransport.
Used to assign distinct particle-hole symmetries to the two sectors; phenomenological rather than derived from a microscopic Hamiltonian in the abstract.
standard math Standard semiclassical Boltzmann transport and particle-hole symmetry classification of thermoelectric and Hall responses.
Background transport theory assumed throughout the comparison of S(T), S(H), and Hall.

invented entities (1)

Disconnected Fermi-liquid islands embedded in a compensated Dirac liquid of phase-incoherent d-wave Bogoliubov quasiparticles no independent evidence
purpose: Reconcile conventional zero-field Hall and thermopower with anomalous magnetothermopower and magnetoresistance via two sectors of opposite particle-hole symmetry.
Phenomenological real-space construction introduced in the abstract; not derived from a microscopic model here. Falsifiable in principle by local probes or further transport, but no independent mass, gap, or spectroscopic handle is given in the abstract.

pith-pipeline@v1.1.0-grok45 · 6178 in / 3237 out tokens · 38287 ms · 2026-07-15T06:03:26.599499+00:00 · methodology

0 comments

read the original abstract

Here, we report magnetothermopower measurements on overdoped (Bi,Pb)2(Sr,La)2CuO6+delta (Bi2201) single crystals in magnetic fields up to 35 T. Whereas the temperature dependence of the zero-field Seebeck coefficient S(T) can be captured using Boltzmann transport theory, the field-dependent response S(H) cannot. Instead, the magnetothermopower contains a large additional contribution whose field and temperature dependence is consistent with the presence of short-range superconducting order well above Tc. Combined with earlier Hall and magnetoresistance results, these data imply that the overdoped cuprate strange metal contains two transport sectors with distinct particle-hole symmetry: a conventional particle-hole-asymmetric Fermi-liquid (FL) contribution governing the Hall effect and the zero-field thermopower, and a nearly particle-hole-symmetric sector dominating the anomalous longitudinal magnetotransport. We formulate a phenomenological real-space model in which disconnected FL islands are embedded in a compensated Dirac liquid of phase-incoherent d-wave Bogoliubov quasiparticles. This picture reconciles conventional zero-field transport with anomalous magnetothermopower and magnetoresistance and offers a concrete framework for thinking about strange metallicity in overdoped cuprates.

Magnetothermopower and particle-hole symmetry in a cuprate strange metal

Core claim

What carries the argument

Load-bearing premise

What would settle it

discussion (0)