pith. sign in

arxiv: 2606.25767 · v2 · pith:GTO4ZBZ6new · submitted 2026-06-24 · ❄️ cond-mat.mtrl-sci · cond-mat.mes-hall

Thermoelectric response of a ferroelectric insulator

Ryo Iguchi , Takashi Teranishi , Sakyo Hirose , Ping Tang , Jun Kano , Gerrit E.W. Bauer , Ken-ichi Uchida This is my paper

Pith reviewed 2026-06-26 05:19 UTC · model grok-4.3

classification ❄️ cond-mat.mtrl-sci cond-mat.mes-hall
keywords ferroelectricthermoelectricPeltier effectdisplacement currentbound chargesphase transitionthermal managementdielectric
0
0 comments X

The pith

Ferroelectric materials produce a Peltier thermoelectric response from bound charges with coefficients over 100 V near their phase transition.

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

The paper demonstrates that an alternating electric field applied to a ferroelectric insulator induces temperature gradients through the displacement current associated with its bound charges. This constitutes a form of thermoelectricity in a material without mobile charge carriers. The strength of this effect peaks near the ferroelectric-paraelectric transition, reaching values several orders of magnitude higher than those observed in conventional conductors, suggesting applications in directional thermal management.

Core claim

The observed temperature gradient in the ferroelectric under an ac electric field depends on the field-induced displacement current, representing a Peltier effect in a dielectric material. Its coefficient exceeds 100 V around the ferroelectric-paraelectric phase transition, which is several orders of magnitude greater than reported values in conductors. This uncovers previously hidden functionalities of ferroelectric materials for thermal management by directional heat transport.

What carries the argument

The Peltier effect driven by the field-induced displacement current of bound charges in the ferroelectric insulator.

If this is right

  • The effect allows for directional heat transport using bound charges in ferroelectrics.
  • The thermoelectric coefficient is maximized near the phase transition.
  • Ferroelectrics can enable thermal management without moving parts or mobile charges.
  • The response can be measured using multi-harmonic lock-in thermography under ac fields.

Where Pith is reading between the lines

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

  • This mechanism may extend to other polar dielectrics with large changes in polarization for similar thermoelectric responses.
  • Electric-field control of heat flow could be integrated into ferroelectric-based capacitors or memory devices.
  • Frequency-dependent studies might identify optimal operating conditions for practical thermal applications.

Load-bearing premise

The temperature changes result only from the Peltier response to the displacement current of bound charges without contributions from Joule heating or experimental artifacts.

What would settle it

A measurement in which the temperature gradient disappears when the displacement current is suppressed while the applied electric field strength remains constant.

Figures

Figures reproduced from arXiv: 2606.25767 by Gerrit E.W. Bauer, Jun Kano, Ken-ichi Uchida, Ping Tang, Ryo Iguchi, Sakyo Hirose, Takashi Teranishi.

Figure 1
Figure 1. Figure 1: Peltier response to ac and dc electric fields in dielectric insulators and conductors, respectively. In conductors, the application of Eext induces both charge (𝑗𝑐 = 𝜎𝐸ext ) and Peltier heat (𝑗𝑞 (Π) ) currents for ac and dc electric fields, where 𝜎 denotes the conductivity. In dielectric insulators, a static external electric field (Eext) causes a static polarization (P) but vanishing displacement (𝑗𝑐 = 𝜕𝑡… view at source ↗
Figure 2
Figure 2. Figure 2: Schematic of experimental setup and thermal images. [PITH_FULL_IMAGE:figures/full_fig_p012_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: Frequency dependence of the Peltier response at room temperature. [PITH_FULL_IMAGE:figures/full_fig_p013_3.png] view at source ↗
read the original abstract

Thermoelectric effects enable the conversion between heat and electricity without moving parts. While conventionally associated with mobile charges, we report thermoelectricity caused by bound charges in the form of temperature changes measured by multi-harmonic lock-in thermography of a ferroelectric under an ac electric field. The observed temperature gradient depends on the field-induced displacement current, a Peltier effect in a dielectric material. Its coefficient exceeds 100 V around the ferroelectric-paraelectric phase transition, which is several orders of magnitude greater than reported values in conductors. Our findings uncover previously hidden functionalities of ferroelectric materials for thermal management by directional heat transport in ferroelectrics.

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 / 2 minor

Summary. The manuscript reports an experimental observation of temperature gradients in a ferroelectric material under an applied AC electric field, measured via multi-harmonic lock-in thermography. The authors attribute the ω-frequency component of the gradient to a Peltier-like thermoelectric response arising from the field-induced displacement current of bound charges rather than mobile carriers. They report a thermoelectric coefficient exceeding 100 V near the ferroelectric-paraelectric phase transition, orders of magnitude larger than typical values in conductors, and suggest applications in directional heat transport and thermal management.

Significance. If the central interpretation is substantiated, the result would identify a previously unrecognized thermoelectric mechanism in insulating ferroelectrics driven by bound-charge currents. The reported magnitude near the phase transition and the use of a non-contact thermography method could open routes to field-tunable thermal devices without mobile carriers, provided the effect can be cleanly separated from known field-driven caloric responses.

major comments (2)
  1. [Results and Discussion (interpretation of ω component)] The central claim that the observed spatial temperature gradient arises from a current-driven Peltier response (J_d = dD/dt) rather than a field-driven mechanism requires explicit experimental discrimination. The multi-harmonic lock-in method isolates the ω component from 2ω (Joule) heating, but both the claimed Peltier effect and the electrocaloric effect produce temperature oscillations linear in E at frequency ω. No quantitative test (e.g., dependence of gradient amplitude on drive frequency, phase lag relative to current vs. field, or reversal of electrode polarity while keeping E direction fixed) is described that would falsify an electrocaloric contribution.
  2. [Abstract and Results (coefficient extraction)] The reported coefficient >100 V is stated to be several orders of magnitude larger than in conductors, yet the manuscript supplies no direct comparison of the measured heat flux or effective thermal conductivity under the same conditions, nor an estimate of the fraction of the displacement current that participates in the thermoelectric transport. Without these, the magnitude cannot be assessed as physically consistent with a Peltier mechanism.
minor comments (2)
  1. [Methods] Notation for the thermoelectric coefficient is introduced without an explicit defining equation relating measured ΔT, current density, and geometry; this should be added for reproducibility.
  2. [Figures] Figure captions should state the exact drive frequency, amplitude, and sample thickness used for each thermography dataset.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for their careful reading of the manuscript and for identifying key points that require clarification. We address each major comment below and have revised the manuscript to strengthen the interpretation and quantitative support for our claims.

read point-by-point responses

  1. Referee: [Results and Discussion (interpretation of ω component)] The central claim that the observed spatial temperature gradient arises from a current-driven Peltier response (J_d = dD/dt) rather than a field-driven mechanism requires explicit experimental discrimination. The multi-harmonic lock-in method isolates the ω component from 2ω (Joule) heating, but both the claimed Peltier effect and the electrocaloric effect produce temperature oscillations linear in E at frequency ω. No quantitative test (e.g., dependence of gradient amplitude on drive frequency, phase lag relative to current vs. field, or reversal of electrode polarity while keeping E direction fixed) is described that would falsify an electrocaloric contribution.

    Authors: We agree that explicit discrimination between current-driven and field-driven contributions is necessary. The original manuscript bases the attribution on the observed dependence of the temperature gradient on the displacement current. In the revised version we have added a quantitative analysis of the phase lag between the ω-temperature oscillation and the applied current (as opposed to the field), together with the frequency dependence of the gradient amplitude. These data are inconsistent with a purely field-driven electrocaloric mechanism and support the current-driven interpretation. We also note that electrode-polarity reversal while keeping E fixed is not feasible in the present electrode geometry without altering the sample configuration, but the phase and frequency tests provide the requested falsification criterion. revision: yes

  2. Referee: [Abstract and Results (coefficient extraction)] The reported coefficient >100 V is stated to be several orders of magnitude larger than in conductors, yet the manuscript supplies no direct comparison of the measured heat flux or effective thermal conductivity under the same conditions, nor an estimate of the fraction of the displacement current that participates in the thermoelectric transport. Without these, the magnitude cannot be assessed as physically consistent with a Peltier mechanism.

    Authors: We accept that a direct comparison and participating-fraction estimate are required to assess physical consistency. In the revised manuscript we have added an explicit calculation of the heat flux from the measured temperature gradient using the independently measured thermal conductivity of the ferroelectric. This heat flux is compared to the displacement current density to obtain the effective coefficient, and we provide an order-of-magnitude estimate of the bound-charge fraction that participates near the phase transition. A side-by-side numerical comparison with typical Peltier coefficients in conductors is also included in the discussion section. revision: yes

Circularity Check

0 steps flagged

No derivation chain; purely experimental claim

full rationale

The manuscript reports an experimental observation using multi-harmonic lock-in thermography on a ferroelectric sample under AC drive. No equations, fitted parameters, or derivation steps appear in the abstract or the supplied text. The central attribution (temperature gradient depends on displacement current) is presented as a direct measurement result rather than the output of any self-referential model, ansatz, or self-citation chain. This matches the reader's assessment of zero circularity.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The central claim rests on interpreting the temperature signal as a true Peltier response to displacement current; no free parameters or invented entities are explicitly introduced in the abstract.

axioms (1)
  • domain assumption Measured temperature gradient is caused by Peltier effect from field-induced displacement current of bound charges
    This interpretation is required to attribute the effect to the dielectric rather than conventional mechanisms.

pith-pipeline@v0.9.1-grok · 5650 in / 1138 out tokens · 32285 ms · 2026-06-26T05:19:33.994778+00:00 · methodology

Review history (2 revisions) →

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

54 extracted references

  1. [1]

    G. J. inyder, E. i. Toberer, Complex thermoelectric materials. Nat. Mater. 7, 105–114 (2008)

    2008

  2. [2]

    J. He, T. M. Tritt, Advances in thermoelectric materials research: Looking back and moving forward. Science 357, eaak9997 (2017)

    2017

  3. [3]

    Uchida, i

    K. Uchida, i. Takahashi, K. Harii, J. Ieda, W. Koshibae, K. Ando, i. Maekawa, E. iaitoh, Observation of the spin ieebeck effect. Nature 455, 778–781 (2008)

    2008

  4. [4]

    Uchida, T

    K. Uchida, T. Nonaka, T. Ota, E. iaitoh, Longitudinal spin-ieebeck effect in sintered polycrystalline (Mn,Zn)Fe2O4. Appl. Phys. Lett. 97, 262504 (2010)

    2010

  5. [5]

    G. E. W. Bauer, E. iaitoh, B. J. van Wees, ipin caloritronics. Nat. Mater . 11, 391–399 (2012)

    2012

  6. [6]

    i. R. Boona, R. C. Myers, J. P. Heremans, ipin caloritronics. Energy Environ. Sci. 7, 885–910 (2014)

    2014

  7. [7]

    Marvan, The electric polarization induced by temperature gradient and associated thermoelectric effects

    M. Marvan, The electric polarization induced by temperature gradient and associated thermoelectric effects. Czech J Phys 19, 1240–1245 (1969)

    1969

  8. [8]

    G. E. W. Bauer, R. Iguchi, K. Uchida, Theory of Transport in Ferroelectric Capacitors. Phys. Rev. Lett. 126, 187603 (2021)

    2021

  9. [9]

    i. B. Lang, Sourcebook of Pyroelectricity (CRC Press, 1974)

    1974

  10. [10]

    R. R. Mehta, B. D. iilverman, J. T. Jacobs, Depolarization fields in thin ferroelectric films. J. Appl. Phys. 44, 3379–3385 (1973)

    1973

  11. [11]

    We disregard a polarization current jp carried by the elementary excitations of the ferroelectric order or ferrons (8) that cannot be excited by a spatially constant electric field

  12. [12]

    Dielectric Peltier Effect

    V . A. Trepakov, E. T. Rafikov, M. Marvan, L. Jastrabik, N. P . Divin, Observation of the “Dielectric Peltier Effect.” Europhys. Lett. 21, 891–895 (1993)

    1993

  13. [13]

    Trepakov, E

    V . Trepakov, E. Rafikov, M. Marvan, A. iavinov, L. Jastrabik, Reverse thermopolarization effects in dielectrics. Ferroelectrics Letters Section 19, 51–56 (1995)

    1995

  14. [14]

    Breitenstein, W

    O. Breitenstein, W. Warta, M. Langenkamp, Lock-in Thermography: Basics and Use for Evaluating Electronic Devices and Materials (ipringer-Verlag, Berlin Heidelberg, ed. 2, 2010) Springer Series in Advanced Microelectronics

    2010

  15. [15]

    Alasli, T

    A. Alasli, T. Hirai, H. Nagano, K. Uchida, Measurements of thermoelectric figure of merit based on multi- harmonic thermal analysis of thermographic images. Appl. Phys. Lett. 121, 154104 (2022)

    2022

  16. [16]

    Iguchi, D

    R. Iguchi, D. Fukuda, J. Kano, T. Teranishi, K. Uchida, Direct measurement of electrocaloric effect based on multi-harmonic lock-in thermography. Appl. Phys. Lett. 122, 082903 (2023)

    2023

  17. [17]

    J. Mao, G. Chen, Z. Ren, Thermoelectric cooling materials. Nat. Mater . 20, 454–461 (2021)

    2021

  18. [18]

    Massetti, F

    M. Massetti, F. Jiao, A. J. Ferguson, D. Zhao, K. Wijeratne, A. Würger, J. L. Blackburn, X. Crispin, i. Fabiano, Unconventional Thermoelectric Materials for Energy Harvesting and iensing Applications. Chem. Rev. 121, 12465–12547 (2021)

    2021

  19. [19]

    E. T. Jaynes, Ferroelectricity. (Princeton University Press, Princeton, 1953)

    1953

  20. [20]

    M. E. Lines, A. M. Glass, Principles and Applications of Ferroelectrics and Related Materials (Clarendon Press ; Oxford University Press, Oxford, New York, 2001)

    2001

  21. [21]

    Acosta, N

    M. Acosta, N. Novak, V . Rojas, i. Patel, R. Vaish, J. Koruza, G. A. Rossetti Jr., J. Rödel, BaTiO3-based piezoelectrics: Fundamentals, current status, and perspectives. Appl. Phys. Rev. 4, 041305 (2017)

    2017

  22. [22]

    Jeon, Effect of irTiO3 concentration and sintering temperature on microstructure and dielectric constant of Ba1−xirxTiO3

    J.-H. Jeon, Effect of irTiO3 concentration and sintering temperature on microstructure and dielectric constant of Ba1−xirxTiO3. J. Eur. Ceram. Soc. 24, 1045–1048 (2004)

    2004

  23. [23]

    Teranishi, K

    T. Teranishi, K. Osaki, H. Hayashi, A. Kishimoto, Domain engineering enhanced microwave tunability in nonstoichiometric Ba0.8ir0.2TiO3. J. Am. Ceram. Soc. 101, 723–731 (2018)

    2018

  24. [24]

    Yadav, M

    i. Yadav, M. Chandra, R. Rawat, V . iathe, A. K. iinha, K. iingh, itructural correlations in the enhancement of ferroelectric property of ir doped BaTiO3. J. Phys.: Condens. Matter 32, 445402 (2020)

    2020

  25. [25]

    Tanaka, R

    Y . Tanaka, R. Iguchi, T. Teranishi, i. Kondo, A. Kishimoto, Permittivity and remanent polarization contributions to the electrocaloric effect in (Ba, ir)TiO3 under unipolar field. Appl. Phys. Lett. 126, 132902 (2025)

    2025

  26. [26]

    Uchida, R

    K. Uchida, R. Iguchi, ipintronic Thermal Management. J. Phys. Soc. Jpn. 90, 122001 (2021)

    2021

  27. [27]

    C. B. iawyer, C. H. Tower, Rochelle ialt as a Dielectric. Phys. Rev. 35, 269–273 (1930)

    1930

  28. [28]

    G. D. Mahan, The Low-Temperature ieebeck Coefficient in Insulators. J. Electron. Mater. 44, 431–434 (2014)

    2014

  29. [29]

    Nasir Khan, H.-T

    M. Nasir Khan, H.-T. Kim, H. Minami, H. Uwe, Thermoelectric properties of niobium doped hexagonal barium titanate. Mater. Lett. 47, 95–101 (2001)

    2001

  30. [30]

    Kolodiazhnyi, A

    T. Kolodiazhnyi, A. Petric, M. Niewczas, C. Bridges, A. iafa-iefat, J. E. Greedan, Thermoelectric power, Hall effect, and mobility of n-type BaTiO3. Phys. Rev. B 68, 085205 (2003)

    2003

  31. [31]

    H. Muta, K. Kurosaki, i. Yamanaka, Thermoelectric properties of doped BaTiO3–irTiO3 solid solution. J. Alloys Compd. 368, 22–24 (2004)

    2004

  32. [32]

    Uchida, i

    K. Uchida, i. Daimon, R. Iguchi, E. iaitoh, Observation of anisotropic magneto-Peltier effect in nickel. Nature 558, 95–99 (2018)

    2018

  33. [33]

    Miura, H

    A. Miura, H. iepehri-Amin, K. Masuda, H. Tsuchiura, Y . Miura, R. Iguchi, Y . iakuraba, J. ihiomi, K. Hono, K. Uchida, Observation of anomalous Ettingshausen effect and large transverse thermoelectric conductivity in permanent magnets. Appl. Phys. Lett. 115, 222403 (2019)

    2019

  34. [34]

    V . A. Trepakov, K. M. Nurieva, A. K. Tagantsev, Recent developments of the thermopolarization effect investigation. Ferroelectrics 94, 377–381 (1989)

    1989

  35. [35]

    itrukov, A

    B. itrukov, A. Davtyan, i. Krotov, Electrothermo-Gradient Effect in TGi Crystals Near Tk. Fiz. Tverd. Tela 27, 364–366 (1985)

    1985

  36. [36]

    Nurieva, A

    K. Nurieva, A. Tagantsev, V . Trepakov, V . Varikash, Observation of Thermal Polarization Effect in Piezoelectrics (kdp). Fiz. Tverd. Tela 31, 130–134 (1989)

    1989

  37. [37]

    Rafikov, A

    E. Rafikov, A. iavinov, L. Jastrabik, V . Trepakov, Frequency and temperature dependence of the thermopolarization response in dynamic investigations. physica status solidi (a) 144, 471–477 (1994)

    1994

  38. [38]

    A. L. Kholkin, V . A. Trepakov, G. A. imolenskiǐ, Thermopolarization currents in dielectrics. JETP Lett. 35, 124 (1982)

    1982

  39. [39]

    G. A. imolenskii, A. K. Tagantsev, A. L. Kholkin, V . A. Trepakov, A. V . Davydov, THERMOPOLARIZATION EFFECT IN FERROELECTRICi. Izv. Akad. Nauk SSSR, Ser . Khim. 47, 598– 602 (1983)

    1983

  40. [40]

    A. J. H. Mante, J. V olger, The thermal conductivity of BaTiO3 in the neighbourhood of its ferroelectric transition temperatures. Phys. Lett. A 24, 139–140 (1967)

    1967

  41. [41]

    P. Tang, R. Iguchi, K. Uchida, G. E. W. Bauer, Excitations of the ferroelectric order. Phys. Rev. B 106, L081105 (2022)

    2022

  42. [42]

    H. Yang, P. Y an, G. E. W. Bauer, Polarization transfer force on ferroelectric domain walls. arXiv, arXiv:2603.10460 (2026)

    arXiv 2026

  43. [43]

    D. R. Callaby, Domain Wall Velocities and the iurface Layer in BaTiO3. J. Appl. Phys. 36, 2751–2760 (1965)

    1965

  44. [44]

    Y.-H. ihin, I. Grinberg, I.-W. Chen, A. M. Rappe, Nucleation and growth mechanism of ferroelectric domain- wall motion. Nature 449, 881–884 (2007)

    2007

  45. [45]

    Electrocaloric Effect: Theory, Measurements, and Applications

    Z. Kutnjak, B. Rožič, R. Pirc, “Electrocaloric Effect: Theory, Measurements, and Applications” in Wiley Encyclopedia of Electrical and Electronics Engineering (American Cancer iociety, 2015), pp. 1–19

    2015

  46. [46]

    R. Ma, Z. Zhang, K. Tong, D. Huber, R. Kornbluh, Y . i. Ju, Q. Pei, Highly efficient electrocaloric cooling with electrostatic actuation. Science 357, 1130–1134 (2017)

    2017

  47. [47]

    Theory of an active magnetic regenerative refrigerator

    J. A. Barclay, “Theory of an active magnetic regenerative refrigerator” (No. LA-UR-83-1251; CONF- 821237-1, 1981). Los Alamos National Lab., NM (UiA)

    1981

  48. [48]

    Richard, A

    M.-A. Richard, A. M. Rowe, R. Chahine, Magnetic refrigeration: iingle and multimaterial active magnetic regenerator experiments. J. Appl. Phys. 95, 2146–2150 (2004)

    2004

  49. [49]

    X. Moya, E. Defay, V . Heine, N. D. Mathur, Too cool to work. Nat. Phys. 11, 202–205 (2015)

    2015

  50. [50]

    i. R. Boona, J. P. Heremans, Magnon thermal mean free path in yttrium iron garnet. Phys. Rev. B 90, 064421 (2014)

    2014

  51. [51]

    Nakayama, B

    H. Nakayama, B. Xu, i. Iwamoto, K. Y amamoto, R. Iguchi, A. Miura, T. Hirai, Y . Miura, Y . iakuraba, J. ihiomi, K. Uchida, Above-room-temperature giant thermal conductivity switching in spintronic multilayers. Appl. Phys. Lett. 118, 042409 (2021)

    2021

  52. [52]

    Hirai, T

    T. Hirai, T. Morita, i. Biswas, J. Uzuhashi, T. Yagi, Y . Yamashita, V . K. Kushwaha, F. Makino, R. Modak, Y . iakuraba, T. Ohkubo, R. Guo, B. Xu, J. ihiomi, D. Chiba, K. Uchida, Non-Equilibrium Magnon Engineering Enabling iignificant Thermal Transport Modulation. Adv. Func. Mater . 35, 2506554 (2025)

    2025

  53. [53]

    B. L. Wooten, R. Iguchi, P . Tang, J. i. Kang, K. Uchida, G. E. W. Bauer, J. P. Heremans, Electric field– dependent phonon spectrum and heat conduction in ferroelectrics. Sci. Adv. 9, eadd7194 (2023)

    2023

  54. [54]

    Magnetic Thermal Management Materials

    P. Upreti, D. Rashadfar, R. iahul, D. L. Abernathy, J. P . Heremans, R. P. Hermann, M. E. Manley, Electric Field Control of Phonon Lifetimes and Thermal Conductivity in Relaxor-Based Ferroelectric. PRX Energy 5, 013001 (2026). Acknowledgments R.I. and K.U. thank J.P. Heremans for fruitful discussions and M. Isomura and D. Fukuda for technical assistance. ...

    2026