Abstract
We consider nonperturbative vacuum polarization effects in the supercritical region for a planar Dirac–Coulomb system with a supercritical extended axially symmetric Coulomb source with a charge \(Z > Z_{{\rm cr},1}\) and radius \(R_0\) in the magnetic field with an axial-vector potential. We study the behavior of the vacuum charge and vacuum current densities, \(\rho_{\mathrm{VP}}(\vec r\,)\) and \(\vec{j}_{\mathrm{VP}}(\vec r\,)\). We focus on the divergence in the theory corresponding to the renormalization and convergence of partial series for \(\rho_{\mathrm{VP}}(\vec r\,)\) and \(\vec{j}_{\mathrm{VP}}(\vec r\,)\). We stress that in contrast to the vacuum charge density, the partial channels with large values of the third projection of the total angular momentum \(|m_j|\) must be taken into account in calculating the vacuum current density in the presence of an external magnetic field localized in the range \(R_1>R_0\). We show that in the presence of a supercritical Coulomb source, the induced magnetic field can enhance the original magnetic field for certain values of parameters of the external vector potential.
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References
A. K. Geim and K. S. Novoselov, “The rise of graphene,” Nature Mater., 6, 183–191 (2007).
A. V. Shytov, M. I. Katsnelson, and L. S. Levitov, “Vacuum polarization and screening of supercritical impurities in graphene,” Phys. Rev. Lett., 99, 236801, 4 pp. (2007).
K. S. Novoselov, A. K. Geim, S. V. Morozov, D. Jiang, M. I. Katsnelson, I. V. Grigorieva, S. V. Dubonos, and A. A. Firsov, “Two-dimensional gas of massless Dirac fermions in graphene,” Nature, 438, 197–200 (2005).
S. V. Morozov, K. S. Novoselov, M. I. Katsnelson, F. Schedin, D. C. Elias, J. A. Jaszczak, and A. K. Geim, “Giant intrinsic carrier mobilities in graphene and its bilayer,” Phys. Rev. Lett., 100, 016602, 4 pp. (2008).
V. M. Kuleshov, V. D. Mur, N. B. Narozhny, A. M. Fedotov, and Y. E. Lozovik, “Coulomb problem for graphene with the gapped electron spectrum,” JETP Lett., 101, 264–270 (2015).
V. M. Kuleshov, V. D. Mur, N. B. Narozhny, A. M. Fedotov, Y. E. Lozovik, and V. S. Popov, “Coulomb problem for a \(Z>Z_\mathrm{cr}\) nucleus,” Phys. Usp., 58, 785–791 (2015).
V. N. Kotov, V. M. Pereira, and B. Uchoa, “Polarization charge distribution in gapped graphene: Perturbation theory and exact diagonalization analysis,” Phys. Rev. B, 78, 075433, 5 pp. (2008).
V. N. Kotov, B. Uchoa, V. M. Pereira, F. Guinea, and A. H. C. Neto, “Electron-electron interactions in graphene: Current status and perspectives,” Rev. Modern Phys., 84, 1067–1125 (2012).
A. Bubnov, N. Gubina, and V. Zhukovsky, “Vacuum current induced by an axial-vector condensate and electron anomalous magnetic moment in a magnetic field,” Phys. Rev. D, 96, 016011, 10 pp. (2017).
P. Górnicki, “Aharonov–Bohm effect and vacuum polarization,” Ann. Phys., 202, 271–296 (1990).
H.-N. Li, D. A. Coker, and A. S. Goldhaber, “Self-consistent solutions for vacuum currents around a magnetic flux string,” Phys. Rev. D, 47, 694–702 (1993).
R. Jackiw, A. I. Milstein, S.-Y. Pi, and I. S. Terekhov, “Induced current and Aharonov–Bohm effect in graphene,” Phys. Rev. B, 80, 033413, 3 pp. (2009).
Y. Nishida, “Vacuum polarization of graphene with a supercritical coulomb impurity: Low-energy universality and discrete scale invariance,” Phys. Rev. B, 90, 165414, 6 pp. (2014).
V. Khalilov and I. Mamsurov, “Planar density of vacuum charge induced by a supercritical coulomb potential,” Phys. Lett. B, 769, 152–158 (2017).
V. R. Khalilov and K. E. Lee, “Planar massless fermions in couloumb and Aharonov–Bohm potentials,” Internat. J. Modern Phys. A, 27, 1250169, 14 pp. (2012).
A. I. Milstein and I. S. Terekhov, “Induced charge generated by a potential well in graphene,” Phys. Rev. B, 81, 125419, 5 pp. (2010).
A. I. Milstein and I. S. Terekhov, “Induced current in the presence of a magnetic flux tube of small radius,” Phys. Rev. B, 83, 075420, 5 pp. (2011).
Yu. A. Sitenko and N. D. Vlasii, “Vacuum polarization effects on graphitic nanocones,” J. Phys.: Conf. Ser., 129, 012008, 9 pp. (2008).
A. Davydov, K. Sveshnikov, and Yu. Voronina, “Nonperturbative vacuum polarization effects in two-dimensional supercritical Dirac–Coulomb system I. Vacuum charge density,” Internat. J. Modern Phys. A, 33, 1850004, 25 pp. (2018); arXiv:1712.02704.
Yu. S. Voronina, A. S. Davydov, and K. A. Sveshnikov, “Vacuum effects for a one-dimensional “hydrogen atom” with \(Z>Z_{\mathrm{cr}}\),” Theoret. and Math. Phys., 193, 1647–1674 (2017).
K. A. Sveshnikov, Yu. S. Voronina, A. S. Davydov, and P. A. Grashin, “Essentially nonperturbative vacuum polarization effects in a two-dimensional Dirac–Coulomb system with \(Z>Z_\mathrm{cr}\): Vacuum charge density,” Theoret. and Math. Phys., 198, 331–362 (2019).
K. A. Sveshnikov, Yu. S. Voronina, A. S. Davydov, and P. A. Grashin, “Essentially nonperturbative vacuum polarization effects in a two-dimensional Dirac–Coulomb system for \(Z>Z_{\text{cr}}\): Vacuum polarization effects,” Theoret. and Math. Phys., 199, 533–561 (2019).
A. Davydov, K. Sveshnikov, and Yu. Voronina, “Nonperturbative vacuum polarization effects in two-dimensional supercritical Dirac–Coulomb system II. Vacuum energy,” Internat. J. Modern Phys. A, 33, 1850005 (2018); arXiv:1712.02703.
H. Bateman and A. Erdélyi, Higher Transcendental Functions, Vol. 1, McGraw-Hill, New York (1953).
P. A. Grashin and K. A. Sveshnikov, “Ferromagnetic phase in graphene-based planar heterostructures induced by charged impurity,” Ann. Phys., 532, 1900351, 12 pp. (2020).
Acknowledgments
The authors thank Professor K. A. Sveshnikov (Faculty of Physics, Moscow State University) for stating the problem and P. A. Grashin (Faculty of Physics, Moscow State University) for the useful discussions.
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Translated from Teoreticheskaya i Matematicheskaya Fizika, 2021, Vol. 208, pp. 122-144 https://doi.org/10.4213/tmf10048.
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Davydov, A.S., Krasnov, A.A. & Kuz’min, V.A. Vacuum charge and current densities in the supercritical two-dimensional Dirac–Coulomb system in a magnetic field with an axial-vector potential. Theor Math Phys 208, 958–976 (2021). https://doi.org/10.1134/S0040577921070096
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DOI: https://doi.org/10.1134/S0040577921070096