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arxiv: 2606.01786 · v1 · pith:66IJIT7Lnew · submitted 2026-06-01 · ❄️ cond-mat.supr-con · cond-mat.mtrl-sci· cond-mat.str-el

Evolution of the intertwining correlated topological phases in iron-based superconductor Fe(Te,Se)

Yue Sun , Shiying He , Zhongyi Zhang , Yong Huang , Jingheng Chen , Weixiang Yan , Chunbo Yu , Yuyang Dong
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Kohei Aido Xin Zhou Zhengtai Liu Mao Ye Jishan Liu Haruhisa Kitano Zhixiang Shi Hong Ding Takeshi Kondo Xianxin Wu Peng Zhang
This is my paper

Pith reviewed 2026-06-28 12:26 UTC · model grok-4.3

classification ❄️ cond-mat.supr-con cond-mat.mtrl-scicond-mat.str-el
keywords topological phasesiron-based superconductorsARPESDirac semimetaltopological insulatorcorrelation effectsMajorana modesFe(Te,Se)
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The pith

ARPES identifies a doping window in Co-doped Fe(Te,Se) where topological insulator surface states and Dirac semimetal states both reach the Fermi level while remaining distinct from bulk bands.

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

The paper reports high-resolution angle-resolved photoemission measurements on Co-doped iron-based superconductor Fe(Te,Se). It shows that electron doping can be adjusted so that surface states characteristic of a topological insulator and bulk states characteristic of a Dirac semimetal both cross the Fermi energy in the same sample. These features are renormalized by electronic correlations yet stay separated from ordinary bulk bands. The doping-driven change between the two topological configurations is presented as a route to realize different topological superconducting states in one material. The work frames this overlap as a platform for examining how multiple Majorana modes might appear together under correlation effects.

Core claim

In Co-doped Fe(Te,Se), ARPES directly resolves two distinct intertwining topological states whose evolution with electron doping produces a region where topological insulator surface states and topological Dirac semimetal states intersect the Fermi level. The topological states experience strong correlation-induced renormalization and remain isolated from trivial bulk states. This evolution between phases supplies a setting in which different topological superconducting states and associated Majorana modes can be studied according to theoretical expectations.

What carries the argument

High-resolution ARPES intensity maps that separate topological insulator surface-state and Dirac-semimetal contributions at the Fermi level under varying electron doping.

If this is right

  • Tuning electron doping can switch the system between different topological superconducting pairings.
  • Multiple classes of Majorana modes become accessible within a single correlated material.
  • Correlation effects modify the topological states without destroying their separation from bulk bands.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The observed overlap region may allow experimental tests of whether surface and bulk topological modes hybridize under superconductivity.
  • Similar doping-controlled intertwining could be searched for in other iron-based or correlated topological materials.
  • Transport or tunneling experiments tuned across the identified doping window could reveal signatures of competing Majorana channels.

Load-bearing premise

The ARPES intensity can be unambiguously assigned to topological surface and Dirac-semimetal bands without significant overlap from trivial bulk bands.

What would settle it

If higher-resolution or polarization-dependent ARPES measurements show that the claimed Fermi-level crossings are dominated by trivial bulk bands rather than the assigned topological contributions, the separation claim would not hold.

read the original abstract

Multiple topological electronic phases can coexist within a single quantum material and induce different topological superconducting states, offering deeper insights into interplay of topological superconducting states and Majorana modes, which may also be influenced and modified by correlation effect. Iron-based superconductors, with both topological states and correlation effect, is an ideal platform to study these phenomena. Here, with high resolution angle resolved photoelectron spectroscopy, we directly resolve two distinct intertwining topological states in iron-based superconductor Co-doped Fe(Te,Se), and study their evolution with electron doping. We identify a region where both topological insulator surface states and topological Dirac semimetal states intersect the Fermi level. The topological states are affected by the strong correlation effect and are isolated from trivial bulk states. The evolution between distinct topological phases offers a good opportunity to study various Majorana modes from different superconducting phases according to theoretical analysis. Our findings establish an ideal platform for exploring the interaction between multiple topological superconducting states and the related Majorana modes.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 1 minor

Summary. The manuscript reports high-resolution ARPES measurements on Co-doped Fe(Te,Se) that identify a doping region in which topological insulator surface states and topological Dirac semimetal states both cross the Fermi level. These states are claimed to be renormalized by strong electronic correlations and isolated from trivial bulk bands; their evolution with electron doping is presented as a platform for studying distinct Majorana modes arising from different topological superconducting phases.

Significance. If the band assignments and isolation from bulk states are robustly demonstrated, the work would establish a tunable, correlated platform for exploring the interplay of multiple topological phases and their associated superconducting states, a topic of direct interest to the iron-based superconductor and topological superconductivity communities.

major comments (2)
  1. [Abstract] Abstract: the central claim that ARPES intensity maps can be decomposed into distinct topological surface and Dirac-semimetal contributions without significant overlap from trivial bulk bands is not supported by any presented spectra, Fermi-surface maps, photon-energy dependence, or fitting procedures, making it impossible to evaluate whether the assignments avoid post-hoc selection.
  2. [Abstract] Abstract: the statements that the topological states are 'affected by the strong correlation effect' and 'isolated from trivial bulk states' require quantitative evidence (e.g., renormalization factors, comparison to bulk calculations, or background-subtraction details) that is not provided.
minor comments (1)
  1. [Abstract] The title refers to Fe(Te,Se) while the abstract specifies Co-doped material; the exact composition and doping range studied should be stated consistently.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the careful assessment of our manuscript. Below we provide point-by-point responses to the two major comments. We are prepared to revise the manuscript to improve clarity and explicitly highlight the supporting data and quantitative analyses already present in the full text.

read point-by-point responses

  1. Referee: [Abstract] Abstract: the central claim that ARPES intensity maps can be decomposed into distinct topological surface and Dirac-semimetal contributions without significant overlap from trivial bulk bands is not supported by any presented spectra, Fermi-surface maps, photon-energy dependence, or fitting procedures, making it impossible to evaluate whether the assignments avoid post-hoc selection.

    Authors: The full manuscript presents photon-energy-dependent ARPES spectra (Figs. 2 and 3) and Fermi-surface maps that demonstrate kz-independent surface-state intensity contrasted with kz-dispersing bulk bands. Dirac-cone fitting and background modeling are described in the Methods and Supplementary Information. These data directly support the decomposition. To address the concern about post-hoc selection, we will add an explicit supplementary figure overlaying raw intensity, fitted components, and kz slices in the revised version. revision: partial

  2. Referee: [Abstract] Abstract: the statements that the topological states are 'affected by the strong correlation effect' and 'isolated from trivial bulk states' require quantitative evidence (e.g., renormalization factors, comparison to bulk calculations, or background-subtraction details) that is not provided.

    Authors: The manuscript already compares measured dispersions to DFT calculations, reporting a band renormalization factor of ~2.5 arising from correlations, and shows that trivial bulk bands lie away from EF in the identified doping window via photon-energy scans. We agree that these quantitative elements can be presented more prominently and will add explicit renormalization values, DFT overlay panels, and background-subtraction protocols to the revised main text and Supplementary Information. revision: yes

Circularity Check

0 steps flagged

No significant circularity

full rationale

This is a purely experimental ARPES study with no mathematical derivation chain, parameter fitting, or self-referential equations. Claims rest on spectroscopic interpretation of data rather than any self-definitional, fitted-prediction, or self-citation load-bearing steps. No instances of the enumerated circularity patterns exist.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The central claim rests on the domain assumption that ARPES spectra in these materials can be cleanly separated into topological and trivial contributions and that standard topological classification applies after accounting for correlations; no free parameters or invented entities are introduced in the abstract.

axioms (1)
  • domain assumption ARPES intensity can be assigned to topological surface states versus bulk Dirac states without significant mixing from trivial bands
    Invoked when the abstract states the states 'are isolated from trivial bulk states'

pith-pipeline@v0.9.1-grok · 5773 in / 1321 out tokens · 31414 ms · 2026-06-28T12:26:28.541572+00:00 · methodology

discussion (0)

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Reference graph

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