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arxiv: 2604.12701 · v1 · submitted 2026-04-14 · ❄️ cond-mat.mes-hall · cond-mat.supr-con

Supercurrent-induced phonon angular momentum

Pith reviewed 2026-05-10 14:37 UTC · model grok-4.3

classification ❄️ cond-mat.mes-hall cond-mat.supr-con
keywords supercurrent-induced phonon angular momentummixed parity superconductorss-wave superconductorsspin-orbit couplingperturbative calculationelectron-phonon interactionangular momentum transfer
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0 comments X

The pith

Supercurrents induce angular momentum in phonons in mixed-parity and spin-orbit-coupled superconductors.

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

The paper proposes that a supercurrent flowing through certain superconductors can induce angular momentum in the phonons, which are the quanta of lattice vibrations. This is shown for mixed parity superconductors and for conventional s-wave superconductors that include spin-orbit coupling. Analytical expressions for this induced angular momentum are derived using perturbative methods. If this holds, it reveals a direct coupling between the superconducting current and the mechanical degrees of freedom of the crystal lattice, potentially allowing control of phonon properties through electrical means.

Core claim

We propose a mechanism of supercurrent-induced phonon angular momentum in mixed parity superconductors and s-wave superconductors with spin orbit coupling. We derive analytical expressions of phonon angular momentum induced by the supercurrent by perturbative calculation. The physical interpretation of this effect is also discussed.

What carries the argument

Perturbative calculation of supercurrent-induced phonon angular momentum via electron-phonon coupling in the presence of mixed-parity pairing or spin-orbit coupling.

Load-bearing premise

The perturbative calculation remains valid for the supercurrent-induced phonon angular momentum and the chosen models for mixed-parity pairing and spin-orbit coupling accurately capture the relevant physics.

What would settle it

An experimental observation of zero phonon angular momentum in a supercurrent-carrying mixed-parity superconductor would falsify the proposed mechanism.

Figures

Figures reproduced from arXiv: 2604.12701 by Takehito Yokoyama.

Figure 1
Figure 1. Figure 1: FIG. 1: Schematic diagram of the model. The application [PITH_FULL_IMAGE:figures/full_fig_p001_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: FIG. 2: The diagrammatic representations of the phonon [PITH_FULL_IMAGE:figures/full_fig_p002_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: FIG. 3: The diagrammatic representations of the phonon [PITH_FULL_IMAGE:figures/full_fig_p004_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: FIG. 4: The diagrammatic representations of the phonon [PITH_FULL_IMAGE:figures/full_fig_p005_4.png] view at source ↗
read the original abstract

We propose a mechanism of supercurrent-induced phonon angular momentum in mixed parity superconductors and s-wave superconductors with spin orbit coupling. We derive analytical expressions of phonon angular momentum induced by the supercurrent by perturbative calculation. The physical interpretation of this effect is also discussed.

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 proposes a mechanism for supercurrent-induced phonon angular momentum in mixed-parity superconductors and in s-wave superconductors with spin-orbit coupling. It derives analytical expressions for the induced phonon angular momentum via perturbative calculations starting from standard superconducting models and discusses the physical interpretation of the effect.

Significance. If the perturbative expressions are valid and reduce correctly to known limits, the result would identify a previously unexplored channel for angular-momentum transfer between supercurrent and lattice degrees of freedom. The analytical character of the derivation is a potential strength, but the absence of explicit validity bounds or consistency checks limits immediate impact on the field.

major comments (2)
  1. [Abstract / derivation] Abstract and derivation section: the perturbative expressions for phonon angular momentum are presented without an explicit bound on the expansion parameter (supercurrent velocity or pair momentum q) relative to the gap Δ or critical current. This is load-bearing for the central claim, as higher-order corrections could dominate for any realistic finite supercurrent (see skeptic note on perturbative validity).
  2. [Results / discussion] No reduction to known limits is shown (e.g., vanishing SOC strength, pure s-wave without parity mixing, or q→0). Without these checks the expressions cannot be validated against established results for phonon or quasiparticle angular momentum.
minor comments (2)
  1. [Abstract] The abstract states that analytical expressions were derived but does not display the leading-order formula or the key assumptions (pairing symmetry, SOC term, phonon mode). Adding the explicit first-order result would improve clarity.
  2. [Throughout] Notation for phonon angular momentum (e.g., L_ph) and the supercurrent-induced correction should be defined once at first use and used consistently.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the careful reading of our manuscript and the constructive comments. We address the major points below and will revise the manuscript to strengthen the presentation of the perturbative regime and consistency checks.

read point-by-point responses
  1. Referee: [Abstract / derivation] Abstract and derivation section: the perturbative expressions for phonon angular momentum are presented without an explicit bound on the expansion parameter (supercurrent velocity or pair momentum q) relative to the gap Δ or critical current. This is load-bearing for the central claim, as higher-order corrections could dominate for any realistic finite supercurrent (see skeptic note on perturbative validity).

    Authors: We agree that an explicit statement of the validity range is important for the central claim. In the revised manuscript we will add a dedicated paragraph in the derivation section specifying the perturbative condition q v_F ≪ Δ (with v_F the Fermi velocity) under which the leading-order expressions are controlled, together with a brief estimate of how this compares to the critical current in representative materials. revision: yes

  2. Referee: [Results / discussion] No reduction to known limits is shown (e.g., vanishing SOC strength, pure s-wave without parity mixing, or q→0). Without these checks the expressions cannot be validated against established results for phonon or quasiparticle angular momentum.

    Authors: We acknowledge that explicit reductions to known limits would strengthen the validation of the analytic expressions. In the revised version we will include calculations demonstrating that the phonon angular momentum vanishes when the spin-orbit coupling is set to zero, in the pure s-wave case without parity mixing, and in the q → 0 limit; these checks will be placed in the results section. revision: yes

Circularity Check

0 steps flagged

No circularity; derivation starts from standard models via perturbation

full rationale

The paper proposes a mechanism and derives analytical expressions for supercurrent-induced phonon angular momentum using perturbative calculations on mixed-parity superconductors and s-wave superconductors with spin-orbit coupling. No steps reduce by construction to fitted inputs, self-definitions, or self-citation chains; the expressions are obtained from standard BCS-like Hamiltonians and perturbative expansions without renaming known results or smuggling ansatze via prior self-citations. The approach is self-contained against external benchmarks of superconducting theory.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Based on abstract only; no explicit free parameters, axioms, or invented entities are stated. The work relies on standard perturbative methods and existing superconductivity models.

pith-pipeline@v0.9.0 · 5316 in / 1030 out tokens · 22427 ms · 2026-05-10T14:37:57.727356+00:00 · methodology

discussion (0)

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Reference graph

Works this paper leans on

64 extracted references · 64 canonical work pages

  1. [1]

    Zhang and Q

    L. Zhang and Q. Niu, Angular Momentum of Phonons and the Einstein-de Haas Effect, Phys. Rev. Lett. 112, 085503 (2014)

  2. [2]

    Zhang and Q

    L. Zhang and Q. Niu, Chiral Phonons at High-Symmetry Points in Monolayer Hexagonal Lattices, Phys. Rev. Lett. 115, 115502 (2015)

  3. [3]

    Q. Wang, S. Li, J. Zhu, H. Chen, W. Wu, W. Gao, L. Zhang, and S. A. Yang, Phys. Rev. B 105, 104301 (2022)

  4. [4]

    Zhang, Z

    T. Zhang, Z. Huang, Z. Pan, L. Du, G. Zhang, and S. Murakami, Weyl phonons in chiral crystals, Nano Lett. 23, 7561 (2023)

  5. [5]

    D. M. Juraschek, R. M. Geilhufe, H. Zhu, M. Basini, P. Baum, A. Baydin, S. Chaudhary, M. Fechner, B. Flebus, G. Grissonnanche, A. I. Kirilyuk, M. Lemeshko, S. F. Maehrlein, M. Mignolet, S. Murakami, Q. Niu, U. Nowak, C. P. Romao, H. Rostami, T. Satoh, N. A. Spaldin, H. Ueda, and L. Zhang, Chiral phonons, Nat. Phys. 21, 1532 (2025)

  6. [6]

    Phononic helical nodal lines withPTprotection inmob 2,

    T. Zhang, Y. Liu, H. Miao, and S. Murakami, New Advances in Phonons: From Band Topology to Quasiparticle Chirality, arXiv:2505.06179

  7. [7]

    H. Zhu, J. Yi, M.-Y. Li, J. Xiao, L. Zhang, C.-W. Yang, R.A. Kaindl, L.-J. Li, Y. Wang, and X. Zhang, Observation of chiral phonons, Science 359, 579 (2018)

  8. [8]

    X. Chen, X. Lu, S. Dubey, Q. Yao, S. Liu, A. Ataei, X. Wang, M. Dion, Q. Xiong, L. Zhang, and A. Srivastava, Entanglement of single-photons and chiral phonons in atomically thin WSe2, Nat. Phys. 15, 221 (2019)

  9. [9]

    Z. Li, T. Wang, C. Jin, Z. Lu, Z. Lian, Y. Meng, M. Blei, M. Gao, T. Taniguchi, K. Watanabe, T. Ren, T. Cao, S. Tongay, D. Smirnov, L. Zhang, and S.-F. Shi, Momentum-Dark Intervalley Exciton in Monolayer Tungsten Diselenide Brightened via Chiral Phonon, ACS Nano 13, 14107 (2019)

  10. [10]

    Grissonnanche, S

    G. Grissonnanche, S. Th\' e riault, A. Gourgout, M.-E. Boulanger, E. Lefran c oiss, A. Ataei, F. Lalibert\' e , M. Dion, J.-S. Zhou, S. Pyon, T. Takayama, H. Takagi, N. Dorion-Leyraud, and T. Taillefer, Chiral phonons in the pseudogap phase of cuprates, Nat. Phys. 16, 1108 (2020)

  11. [11]

    Ishito, H

    K. Ishito, H. Mao, Y. Kousaka, Y. Togawa, S. Iwasaki, T. Zhang, S. Murakami, J.-I. Kishine, and T. Satoh, Truly chiral phonons in -HgS, Nat. Phys. 19, 35 (2023)

  12. [12]

    Ishito, H

    K. Ishito, H. Mao, K. Kobayashi, Y. Kousaka, Y. Togawa, H. Kusunose, J. Kishine, and T. Satoh, Chiral phonons: Circularly polarized Raman spectroscopy and ab initio calculations in a chiral crystal tellurium, Chirality 35, 338 (2023)

  13. [13]

    H. Ueda, M. Garc\' i a-Fern\' a ndez, S. Agrestini, C. P. Romao, J. van den Brink, N. A. Spaldin, K.-J. Zhou, and U. Staub, Chiral phonons probed by X rays, Nature 618, 946 (2023)

  14. [14]

    Zhang, N

    H. Zhang, N. Peshcherenko, F. Yang, T. Z. Ward, P. Raghuvanshi, L. Lindsay, C. Felser, Y. Zhang, J.-Q. Yan, and H. Miao, Observation of Phonon Angular Momentum, Nat. Phys. 21, 1387 (2025)

  15. [15]

    T. F. Nova, A. Cartella, A. Cantaluppi, M. F\" o rst, D. Bossini, R. V. Mikhaylovskiy, A. V. Kimel, R. Merlin, and A. Cavalleri, An effective magnetic field from optically driven phonons, Nat. Phys. 13, 132 (2017)

  16. [16]

    D. M. Juraschek and N. A. Spaldin, Orbital magnetic moments of phonons, Phys. Rev. Mater. 3, 064405 (2019)

  17. [17]

    R. M. Geilhufe, V. Juri c i\' c , S. Bonetti, J.-X. Zhu, and A. V. Balatsky, Dynamically induced magnetism in KTaO _3 , Phys. Rev. Res. 3, L022011 (2021)

  18. [18]

    D. M. Juraschek, T. Neuman, and P. Narang, Giant effective magnetic fields from optically driven chiral phonons in 4f paramagnets, Phys. Rev. Res. 4, 013129 (2022)

  19. [19]

    Xiong, H

    G. Xiong, H. Chen, D. Ma, and L. Zhang, Effective magnetic fields induced by chiral phonons, Phys. Rev. B 106, 144302 (2022)

  20. [20]

    J. Luo, T. Lin, J. Zhang, X. Chen, E. R. Blackert, R. Xu, B. I. Yakubson, and H. Zhu, Large effective magnetic fields from chiral phonons in rare-earth halides, Science 382, 698 (2023)

  21. [21]

    F. G. G. Hernandez, A. Baydin, S. Chaudhary, F. Tay, I. Katayama, J. Takeda, H. Nojiri, A. K. Okazaki, P. H. O. Rappl, E. Abramof, M. Rodriguez-Vega, G. A. Fiete, and J. Kono, Observation of interplay between phonon chirality and electronic band topology, Sci. Adv. 9, eadj4074 (2023)

  22. [22]

    Chaudhary, D

    S. Chaudhary, D. M. Juraschek, M. Rodriguez-Vega, and G. A. Fiete, Giant effective magnetic moments of chiral phonons from orbit-lattice coupling, Phys. Rev. B 110, 094401 (2024)

  23. [23]

    Merlin, Magnetophononics and the chiral phonon misnomer, PNAS Nexus 4, pgaf002 (2025)

    R. Merlin, Magnetophononics and the chiral phonon misnomer, PNAS Nexus 4, pgaf002 (2025)

  24. [24]

    Hamada and S

    M. Hamada and S. Murakami, Conversion between electron spin and microscopic atomic rotation, Phys. Rev. Res. 2, 023275 (2020)

  25. [25]

    Yao and S

    D. Yao and S. Murakami, Conversion of Chiral Phonons into Magnons in Ferromagnets and Antiferromagnets, J. Phys. Soc. Jpn. 93, 034708 (2024)

  26. [26]

    Wang, M.-Q

    Q. Wang, M.-Q. Long, and Y.-P. Wang, Magnetic moments of chiral phonons induced by coupling with magnons, Phys. Rev. B 110, 024423 (2024)

  27. [27]

    B. Ma, Z. D. Wang, and G. v. Chen, Chiral Phonons Induced from Spin Dynamics via Magnetoelastic Anisotropy, Phys. Rev. Lett. 133, 246604 (2024)

  28. [28]

    Fransson, Y

    J. Fransson, Y. Kapon, L. Brann, S. Yochelis, D. D. Sasselov, Y. Paltiel, and S. F. Ozturk, Chiral Phonons Enhance Ferromagnetism, J. Phys. Chem. Lett. 16, 2001 (2025)

  29. [29]

    Basini, M

    M. Basini, M. Pancaldi, B. Wehinger, M. Udina, V. Unikandanunni, T. Tadano, M. C. Hoffmann, A. V. Balatsky, and S. Bonetti, Terahertz electric-field-driven dynamical multiferroicity in SrTiO _3 , Nature 628, 534 (2024)

  30. [30]

    C. S. Davies, F. G. N. Fennema, A. Tsukamoto, I. Razdolski, A. V. Kimel, and A. Kirilyuk, Phononic switching of magnetization by the ultrafast Barnett effect, Nature 628, 540 (2024)

  31. [31]

    Kahana, D

    T. Kahana, D. A. Bustamante Lopez, and D. M. Juraschek, Light-induced magnetization from magnonic rectification, Sci. Adv. 10, eado0722 (2024)

  32. [32]

    E. Liu, J. van Baren, T. Taniguchi, K. Watanabe, Y.-C. Chang, and C. H. Lui, Valley-selective chiral phonon replicas of dark excitons and trions in monolayer WSe _2 , Phys. Rev. Research 1, 032007(R) (2019)

  33. [33]

    Lujan, J

    D. Lujan, J. Choe, S. Chaudhary, and X. Li, Spin-orbit exciton-induced phonon chirality in a quantum magnet, Proc. Natl. Acad. Sci. U.S.A. 121, e2304360121 (2024)

  34. [34]

    Tateishi, A

    T. Tateishi, A. Kato, and J.-i. Kishine, Electron-Chiral Phonon Coupling, Crystal Angular Momentum, and Phonon Chirality, J. Phys. Soc. Jpn. 94, 053601 (2025)

  35. [35]

    Y. Chen, W. Qin, S. Zhang, P. Cui, Q. Niu, and Z. Zhang, Emergence of chiral phonons in two-dimensional kagome lattices harboring electronic chirality, Phys. Rev. Lett. 135, 126608 (2025)

  36. [36]

    Fransson, Chiral phonon induced spin polarization, Phys

    J. Fransson, Chiral phonon induced spin polarization, Phys. Rev. Res. 5, L022039 (2023)

  37. [37]

    Y. Ren, C. Xiao, D. Saparov, and Q. Niu, Phonon Magnetic Moment from Electronic Topological Magnetization, Phys. Rev. Lett. 127, 186403 (2021)

  38. [38]

    K. Kim, E. Vetter, L. Yan, C. Yang, Z. Wang, R. Sun, Y. Yang, A. H. Comstock, X. Li, J. Zhou, L. Zhang, W. You, D. Sun, and J. Liu, Chiral-phonon-activated spin Seebeck effect, Nat. Mater. 22, 322 (2023)

  39. [39]

    X. Li, J. Zhong, J. Cheng, H. Chen, H. Wang, J. Liu, D. Sun, L. Zhang, and J. Zhou, Chiral phonon activated spin Seebeck effect in chiral materials, Sci. China Phys. Mech. Astron. 67, 237511 (2024)

  40. [40]

    D. Yao, M. Matsuo, and T. Yokoyama, Electric field-induced nonreciprocal spin current due to chiral phonons in chiral-structure superconductors, Appl. Phys. Lett. 124, 162603 (2024)

  41. [41]

    Funato, M

    T. Funato, M. Matsuo, and T. Kato, Chirality-Induced Phonon-Spin Conversion at an Interface, Phys. Rev. Lett. 132, 236201 (2024)

  42. [42]

    X. Qin, C. Yang, D. Sun, J. Liu, and V. Blum, Chiral Phonon-Induced Spin Transport via Microscopic Barnett Effect, Phys. Rev. Lett. 135, 076703 (2025)

  43. [43]

    Nabei, C

    Y. Nabei, C. Yang, H. Sun, H. Jones, T. Mai, T. Wang, R. Bodin, B. Pandey, Z. Wang, Y. Xiong, A. H. Comstock, B. Ewing, J. Bingen, R. Sun, D. Smirnov, W. Zhang, A. Hoffmann, R. Rao, M. Hu, Z. V. Vardeny, B. Yan, X. Li, J. Zhou, J. Liu, and D. Sun, Orbital Seebeck effect induced by chiral phonons, Nat. Phys. (2026). https://doi.org/10.1038/s41567-025-03134-x

  44. [44]

    u ller, C. Schr\

    V. L. Korenev, M. Salewski, I. A. Akimov, V. F. Sapega, L. Langer, I. V. Kalitukha, J. Debus, R. I. Dzhioev, D. R. Yakovlev, D. M\" u ller, C. Schr\" o der, H. H\" o vel, G. Karczewski, M. Wiater, T. Wojtowicz, Yu. G. Kusrayev, and M. Bayer, Long-range p-d exchange interaction in a ferromagnet-semiconductor hybrid structure, Nat. Phys. 12, 85 (2016)

  45. [45]

    S. G. Jeong, J. Kim, A. Seo, S. Park, H. Y. Jeong, Y.-M. Kim, V. Lauter, T. Egami, J. H. Han, and W. S. Choi, Unconventional interlayer exchange coupling via chiral phonons in synthetic magnetic oxide heterostructures, Sci. Adv. 8, eabm4005 (2022)

  46. [46]

    Yokoyama, Spin-Spin Interaction Mediated by Chiral Phonons, J

    T. Yokoyama, Spin-Spin Interaction Mediated by Chiral Phonons, J. Phys. Soc. Jpn. 93, 123705 (2024)

  47. [47]

    Hamada, E

    M. Hamada, E. Minamitani, M. Hirayama, and S. Murakami, Phonon Angular Momentum Induced by the Temperature Gradient, Phys. Rev. Lett. 121, 175301 (2018)

  48. [48]

    V. M. Edelstein, Spin polarization of conduction electrons induced by electric current in two-dimensional asymmetric electron systems, Solid State Commun. 73, 233 (1990)

  49. [49]

    Hamada and S

    M. Hamada and S. Murakami, Phonon rotoelectric effect, Phys. Rev. B 101, 144306 (2020)

  50. [50]

    Yokoyama, Phonon Edelstein effect in chiral metals, Phys

    T. Yokoyama, Phonon Edelstein effect in chiral metals, Phys. Rev. B 112, L020406 (2025)

  51. [51]

    R. R. Birss, Symmetry and Magnetism, Series of Monographs on Selected Topics in Solid State Physics, edited by E. P. Wohlfarth, Vol. 3 (Elsevier North-Holland, 1962)

  52. [52]

    V. A. Kizel', Y. Krasilov, and V. I. Burkov, Experimental studies of gyrotropy of crystals, Sov. Phys. Usp. 17, 745 (1975)

  53. [53]

    Jerphagnon and D

    J. Jerphagnon and D. S. Chemla, Optical activity of crystals, J. Chem. Phys. 65, 1522 (1976)

  54. [54]

    S. D. Ganichev, M. Trushin, and J. Schliemann, Spin polarisation by current, in Spintronics Handbook, 2nd ed., Vol. 2, Chap. 7, edited by E. Y. Tsymbal and I. Z uti\' c (CRC Press, Taylor & Francis Group, 2019)

  55. [55]

    Y. Gao, Y. Pan, J. Zhou, and L. Zhang, Chiral phonon mediated high-temperature superconductivity, Phys. Rev. B 108, 064510 (2023)

  56. [56]

    Yip, Noncentrosymmetric superconductors, Annu

    S. Yip, Noncentrosymmetric superconductors, Annu. Rev. Condens. Matter Phys. 5, 15 (2014)

  57. [57]

    A. A. Burkov, Weyl Metals, Annu. Rev. Condens. Matter Phys. 9, 359 (2018)

  58. [58]

    N. P. Armitage, E. J. Mele, and A. Vishwanath, Weyl and Dirac semimetals in three-dimensional solids, Rev. Mod. Phys. 90, 015001 (2018)

  59. [59]

    D. A. Ivanov and Ya. V. Fominov, Minigap in superconductor-ferromagnet junctions with inhomogeneous magnetization, Phys. Rev. B 73, 214524 (2006)

  60. [60]

    Yokoyama, Floquet engineering triplet superconductivity in superconductors with spin-orbit coupling or altermagnetism, Phys

    T. Yokoyama, Floquet engineering triplet superconductivity in superconductors with spin-orbit coupling or altermagnetism, Phys. Rev. B 112, 024512 (2025)

  61. [61]

    V. M. Edelstein, Magnetoelectric effect in polar superconductors, Phys. Rev. Lett. 75, 2004 (1995)

  62. [62]

    He and K

    W.-Y. He and K. T. Law, Magnetoelectric effects in gyrotropic superconductors, Phys. Rev. Res. 2, 012073(R) (2020)

  63. [63]

    Yokoyama, Relationship between nonunitary mixed parity superconductivity and magnetism with spin-orbit coupling, arXiv:2505.10336

    T. Yokoyama, Relationship between nonunitary mixed parity superconductivity and magnetism with spin-orbit coupling, arXiv:2505.10336

  64. [64]

    A. A. Abrikosov, L. P. Gor'kov, and I. E. Dzyaloshinskii, Methods of Quantum Field Theory in Statistical Physics (New York: Dover, 1963)