- Physical Review Journals
All JournalsPhysics Magazine

Physical Review Research

Reuse & Permissions

It is not necessary to obtain permission to reuse this article or its components as it is available under the terms of the Creative Commons Attribution 4.0 International license. This license permits unrestricted use, distribution, and reproduction in any medium, provided attribution to the author(s) and the published article's title, journal citation, and DOI are maintained. Please note that some figures may have been included with permission from other third parties. It is your responsibility to obtain the proper permission from the rights holder directly for these figures.

Export citation

Export citation

Choose format for download:

Download Citation
  • Letter
  • Open Access

Signature of PT-symmetric non-Hermitian superconductivity in angle-resolved photoelectron fluctuation spectroscopy

Viktoriia Kornich and Björn Trauzettel

  • Institut für Theoretische Physik and Astrophysik, Universität Würzburg, 97074 Würzburg, Germany

PDF

Phys. Rev. Research 4, L022018 – Published 22 April, 2022

DOI: https://doi.org/10.1103/PhysRevResearch.4.L022018

Abstract

We show theoretically that the measurement of a PT-symmetric non-Hermitian superconductor by angle-resolved photoelectron fluctuation spectroscopy (ARPFS) provides a particular signature. In fact, the signal is negative in a single-band case in contrast to the ARPFS signal of Hermitian superconductors. We suggest that the negative fluctuations can be explained by a remarkable pairing phenomenon: If the interaction between electrons in this PT-symmetric non-Hermitian superconductor is attractive, then the interaction between holes (i.e., missing electrons) is repulsive and vice versa. This difference in the sign of the interactions gives rise to negative cross correlations. Here, we propose how such an electron-electron interaction can occur due to the spatiotemporal modulation of the material. We also discuss the observability of this signature in multiband systems.

View figure in article

Physics Subject Headings (PhySH)

Article Text

Supplemental Material

References (39)

  1. Y. Ashida, Z. Gong, and M. Ueda, Non-Hermitian physics, Adv. Phys. 69, 249 (2020).
  2. K. Kawabata, K. Shiozaki, M. Ueda, and M. Sato, Symmetry and Topology in Non-Hermitian Physics, Phys. Rev. X 9, 041015 (2019).
  3. C. M. Bender and S. Boettcher, Real Spectra in Non-Hermitian Hamiltonians Having PT Symmetry, Phys. Rev. Lett. 80, 5243 (1998).
  4. C. M. Bender, Making sense of non-Hermitian Hamiltonians, Rep. Prog. Phys. 70, 947 (2007).
  5. K. G. Makris, R. El-Ganainy, D. N. Christodoulides, and Z. H. Musslimani, Beam Dynamics in PT Symmetric Optical Lattices, Phys. Rev. Lett. 100, 103904 (2008).
  6. A. Guo, G. J. Salamo, D. Duchesne, R. Morandotti, M. Volatier-Ravat, V. Aimez, G. A. Siviloglou, and D. N. Christodoulides, Observation of PT-Symmetry Breaking in Complex Optical Potentials, Phys. Rev. Lett. 103, 093902 (2009).
  7. M. Brandstetter, M. Liertzer, C. Deutsch, P. Klang, J. Schöberl, H. E. Türeci, G. Strasser, K. Unterrainer, and S. Rotter, Reversing the pump dependence of a laser at an exceptional point, Nat. Commun. 5, 4034 (2014).
  8. Ş. K. Özdemir, S. Rotter, F. Nori, and L. Yang, Parity-time symmetry and exceptional points in photonics, Nat. Mater. 18, 783 (2019).
  9. S. Klaiman, U. Günther, and N. Moiseyev, Visualization of Branch Points in PT-Symmetric Waveguides, Phys. Rev. Lett. 101, 080402 (2008).
  10. S. Longhi, PT-symmetric laser absorber, Phys. Rev. A 82, 031801(R) (2010).
  11. A. Regensburger, C. Bersch, M.-A. Miri, G. Onishchukov, D. N. Christodoulides, and U. Peschel, Parity-time synthetic photonic lattices, Nature (London) 488, 167 (2012).
  12. L. Feng, Z. J. Wong, R. M. Ma, Y. Wang, and X. Zhang, Single-mode laser by parity-time symmetry breaking, Science 346, 972 (2014).
  13. H. Hodaei, M.-A. Miri, M. Heinrich, D. N. Christodoulides, and M. Khajavikhan, Parity-time-symmetric microring lasers, Science 346, 975 (2014).
  14. K. Kawabata, Y. Ashida, H. Katsura, and M. Ueda, Parity-time-symmetric topological superconductor, Phys. Rev. B 98, 085116 (2018).
  15. W. Yang, C. Xu, and C. Wu, Single branch of chiral Majorana modes from doubly degenerate Fermi surfaces, Phys. Rev. Research 2, 042047(R) (2020).
  16. N. M. Chtchelkatchev, A. A. Golubov, T. I. Baturina, and V. M. Vinokur, Stimulation of the Fluctuation Superconductivity by PT Symmetry, Phys. Rev. Lett. 109, 150405 (2012).
  17. Y. X. Zhao, A. P. Schnyder, and Z. D. Wang, Unified Theory of PT and CP Invariant Topological Metals and Nodal Superconductors, Phys. Rev. Lett. 116, 156402 (2016).
  18. C. Yuce and Z. Oztas, PT symmetry protected non-Hermitian topological systems, Sci. Rep. 8, 17416 (2018).
  19. D. Wang, C. Li, C. Zhang, M. Kang, X. Zhang, B. Jin, Z. Tian, Y. Li, S. Zhang, J. Han, and W. Zhang, Superconductive PT-symmetry phase transition in metasurfaces, Appl. Phys. Lett. 110, 021104 (2017).
  20. A. Ghatak and T. Das, Theory of superconductivity with non-Hermitian and parity-time reversal symmetric Cooper pairing symmetry, Phys. Rev. B 97, 014512 (2018).
  21. K. Yamamoto, M. Nakagawa, K. Adachi, K. Takasan, M. Ueda, and N. Kawakami, Theory of Non-Hermitian Fermionic Superfluidity with a Complex-Valued Interaction, Phys. Rev. Lett. 123, 123601 (2019).
  22. C. Stahl and M. Eckstein, Noise correlations in time- and angle-resolved photoemission spectroscopy, Phys. Rev. B 99, 241111(R) (2019).
  23. V. Kornich, F. Schlawin, M. A. Sentef, and B. Trauzettel, Direct detection of odd-frequency superconductivity via time- and angle-resolved photoelectron fluctuation spectroscopy, Phys. Rev. Research 3, L042034 (2021).
  24. A. Mostafazadeh, Pseudo-Hermiticity versus PT symmetry: The necessary condition for the reality of the spectrum of a non-Hermitian Hamiltonian, J. Math. Phys. 43, 205 (2002).
  25. See Supplemental Material at http://link.aps.org/supplemental/10.1103/PhysRevResearch.4.L022018 for (1) derivation of the evolution operators for left and right state vectors, (2) Fourier transformation of anomalous Green's functions, and (3) derivation of the electron-electron interaction potential mediated by phonons from two asymmetrically interacting bands.
  26. L. Herviou, N. Regnault, and J. H. Bardarson, Entanglement spectrum and symmetries in non-Hermitian fermionic non-interacting models, SciPost Phys. 7, 069 (2019).
  27. A. Tamai, M. Zingl, E. Rozbicki, E. Cappelli, S. Ricco, A. de la Torre, S. McKeown Walker, F. Y. Bruno, P. D. C. King, W. Meevasana, M. Shi, M. Radovic, N. C. Plumb, A. S. Gibbs, A. P. Mackenzie, C. Berthod, H. U. R. Strand, M. Kim, A. Georges, and F. Baumberger, High-Resolution Photoemission on Sr2RuO4 Reveals Correlation-Enhanced Effective Spin-Orbit Coupling and Dominantly Local Self-Energies, Phys. Rev. X 9, 021048 (2019).
  28. E. M. Nica, R. Yu, and Q. Si, Orbital-selective pairing and superconductivity in iron selenides, npj Quantum Mater. 2, 24 (2017).
  29. H. Ramezani, T. Kottos, R. El-Ganainy, and D. N. Christodoulides, Unidirectional nonlinear PT-symmetric optical structures, Phys. Rev. A 82, 043803 (2010).
  30. C. E. Rüter, K. G. Makris, R. El-Ganainy, D. N. Christodoulides, M. Segev, and D. Kip, Observation of parity-time symmetry in optics, Nat. Phys. 6, 192 (2010).
  31. B. Peng, Ş. K. Özdemir, F. Lei, F. Monifi, M. Gianfreda, G. L. Long, S. Fan, F. Nori, C. M. Bender, and L. Yang, Parity-time-symmetric whispering-gallery microcavities, Nat. Phys. 10, 394 (2014).
  32. C. W. Ling, J. Wang, and K. H. Fung, Formation of nonreciprocal bands in magnetized diatomic plasmonic chains, Phys. Rev. B 92, 165430 (2015).
  33. S. Kanasugi and Y. Yanase, Anapole superconductivity from PT-symmetric mixed-parity interband pairing, Commun. Phys. 5, 39 (2022).
  34. G. Trainiti and M. Ruzzene, Non-reciprocal elastic wave propagation in spatiotemporal periodic structures, New J. Phys. 18, 083047 (2016).
  35. M. B. Zanjani, A. R. Davoyan, N. Engheta, and J. R. Lukes, NEMS With broken T symmetry: Graphene based unidirectional acoustic transmission lines, Sci. Rep. 5, 9926 (2015).
  36. M. B. Zanjani, A. R. Davoyan, A. M. Mahmoud, N. Engheta, and J. R. Lukes, One-way phonon isolation in acoustic waveguides, Appl. Phys. Lett. 104, 081905 (2014).
  37. C. Rasmussen, L. Quan, and A. Alù, Acoustic nonreciprocity, J. Appl. Phys. 129, 210903 (2021).
  38. M. Hong, Y. Wang, T. Feng, Q. Sun, S. Xu, S. Matsumura, S. T. Pantelides, J. Zou, and Z.-G. Chen, Strong phonon-phonon interactions securing extraordinary thermoelectric Ge1−xSbxTe with Zn-alloying-induced band alignment, J. Am. Chem. Soc. 141, 1742 (2019).
  39. E. S. Zijlstra, L. L. Tatarinova, and M. E. Garcia, Laser-induced phonon-phonon interactions in bismuth, Phys. Rev. B 74, 220301(R) (2006).

Outline

Information

Phys. Rev. Research 4, L022018– Published 22 April, 2022
  • Received 13 December 2021
  • Revised 10 March 2022
  • Accepted 11 March 2022
Crossmark - Check for updates button
Creative Commons Logo

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Published by the American Physical Society

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation