- Open Access
Hirota-tau- and Heun-function framework for Dirac vacuum polarization and quantum stabilization of kinks
Phys. Rev. D 113, 116013 – Published 8 June, 2026
DOI: https://doi.org/10.1103/jdzj-s4ng
Abstract
We investigate a modified affine Toda model coupled to matter (ATM), which includes a scalar self-interacting potential and demonstrate that its first-order integrodifferential structure, preserving a deformed Noether-topological current correspondence, provides a consistent framework for fermion-soliton interactions. In this formulation, the fermion-soliton energy is proportional to the soliton’s topological charge. We evaluate the renormalized energy functional, incorporating one-loop quantum corrections, and perform a variational minimization to determine the configuration that extremizes the functional. The fermionic backreaction and the self-interacting scalar critically shape the fermion-kink energy, the in-gap bound-state spectrum, and the fermionic vacuum-polarization energy, yielding well-defined stability minima of the total energy as functions of the fermion and scalar masses and coupling parameters, in the semiclassical approximation. A key result is that the Heun-equation formalism is necessary to construct nonzero-energy bound and scattering states: unlike the tau-function method, which captures only the zero mode, the Heun approach encodes the full scattering data through local solution matching conditions. These results refine the spectral analysis of deformed integrable models. The stability of soliton-fermion configurations has direct implications for topologically protected states in quantum information and condensed-matter systems.
Physics Subject Headings (PhySH)
Article Text
References (37)
- R. Rajaraman, Solitons and Instantons: An Introduction to Solitons and Instantons in Quantum Field Theory, 1st ed. (North Holland, Amsterdam, 1987).
- O. Babelon, D. Bernard, and M. Talon, Introduction to Classical Integrable Systems (Cambridge University Press, Cambridge, England, 2007).
- Y. Frihman and J. Sonnenschein, Non-Perturbative Field Theory. From Two-Dimensional Conformal Field Theory to QCD in Four Dimensions (Cambridge University Press, Cambridge, England, 2010).
- E. Abdalla, M. C. B. Abdalla, and K. D. Rothe, Non-Perturbative Methods in 2 Dimensional Quantum Field Theory (World Scientific, Singapore, 1991).
- L. A. Ferreira, J-L. Gervais, J. Sánchez Guillen, and M. V. Saveliev, Nucl. Phys. B470, 236 (1996).
- H. Blas and L. A. Ferreira, Nucl. Phys. B571, 607 (2000).
- H. Blas, Nucl. Phys. B596, 471 (2001).
- H. Blas, Phys. Rev. D 66, 127701 (2002).
- H. Blas, J. J. Monsalve, R. Quicaño, and J. R. V. Pereira, J. High Energy Phys. 09 (2022) 082.
- H. Blas, J. High Energy Phys. 06 (2024) 007.
- H. Blas and R. Quicaño, Phys. Rev. D 112, 016019 (2025).
- R. Jackiw and C. Rebbi, Phys. Rev. D 13, 3398 (1976).
- V. Klimashonok, I. Perapechka, and Y. Shnir, Phys. Rev. D 100, 105003 (2019).
- I. Perapechka and Y. Shnir, Phys. Rev. D 101, 021701 (2020).
- V. A. Gani, A. Gorina, I. Perapechka, and Y. Shnir, Eur. Phys. J. C 82, 757 (2022).
- L. Shahkarami, A. Mohammadi, and S. S. Gousheh, J. High Energy Phys. 11 (2011) 140.
- S. S. Gousheh, A. Mohammadi, and L. Shahkarami, Eur. Phys. J. C 74, 3020 (2014).
- D. Saadatmand and H. Weigel, Phys. Rev. D 107, 036006 (2023).
- D. Saadatmand and H. Weigel, Universe 10, 13 (2024).
- E. Farhi, N. Graham, R. L. Jaffe, and H. Weigel, Phys. Lett. 475B, 335 (2000).
- E. Farhi, N. Graham, R. L. Jaffe, and H. Weigel, Nucl. Phys. B585, 443 (2000).
- R. S. Maier, Math. Comput. 76, 811 (2007).
- Heun’s Differential Equations, edited by A. Ronveaux (Oxford University Press, Oxford, 1995).
- NIST Handbook of Mathematical Functions, edited by F. W. J. Olver, D. W. Lozier, R. F. Boisvert, and C. W. Clark (Cambridge University Press, Cambridge, England, 2010).
- S. Y. Slavyanov and W. Lay, Special Funcions.A Unified Theory Based on Singularities (Oxford University Press, Oxford, 2000).
- M. Hortacsu, Adv. High Energy Phys. 2018, 8621573 (2018).
- A. Yu. Loginov, Eur. Phys. J. C 82, 662 (2022).
- C. Adam and F. Santamaria, J. High Energy Phys. 12 (2016) 047.
- C. Adam, L. A. Ferreira, E. da Hora, A. Wereszczynski, and W. J. Zakrzewski, J. High Energy Phys. 08 (2013) 062.
- R.-L. Chai, Q.-T. Xie, and X.-L. Liu, Chin. Phys. B 29, 090301 (2020).
- B.-H. Chen, Y. Wu, and Q.-T. Xie, J. Phys. A 46, 035301 (2013).
- Wolfram Research, Inc., Mathematica, Version 12.2. Champaign, IL (2020), https://www.wolfram.com.
- R. Zavin and N. Moiseyev, J. Phys. A 37, 4619 (2004).
- G. Barton, J. Phys. A 18, 479 (1985).
- H. J. de Vega and F. A. Schaposnik, Phys. Rev. D 14, 1100 (1976).
- L. A. Ferreira and Wojtek J. Zakrzewski, J. High Energy Phys. 05 (2011) 130.
- H. Blas, H. F. Callisaya, and J. P. R. Campos, Nucl. Phys. B950, 114852 (2020).