Anomalous One-Particle Properties in the Normal State of a Model with Superconductivity

The main purpose of this study is to investigate the influence of the strong superconducting fluctuations in the d-wave channel on the normal state properties of a simple two-dimensional strongly correlated Fermi-system. We achieve this goal using a thermodynamically self-consistent Baym–Kadanoff conserving Green’s function approximation (formulation is based on a well-defined free energy and conserving particle number, momentum, and energy), which is known to produce reliable results for the s-wave superconductors well beyond the weak coupling limit up to the range where the interaction strength is comparable to the bandwidth of the quasiparticle spectrum. The research shows that pairing correlations above lead to the appearance of a highly anisotropic pseudogap in the electronic spectral function and the destruction of the Fermi surface. We conclude that our results are in remarkable agreement with the available experimental angle-resolved photoemission data on the high temperature superconductors.

Publication year: 
С. 73–79., укр., Іл. 3. Бібліогр.: 27 назв.

1. N.M. Plakida, High-Temperature Superconductivity: Experiment and Theory. UK, London: Springer, 2012.
2. M. Takigawa et al., “Cu And O Nmr-Studies Of The Magnetic-Properties Of Yba2cu3o6.63(Tc=62k)”, Phys. Rev. B, vol. 43, P. 247, 1991.
3. J. Loram et al., “The Electronic Specific-Heat Of Cuprate Superconductors”, Physica C, vol. 134, pp. 235— 240, 1994.
4. C. C. Homes et al., “Optical Conductivity Of C-Axis Oriented Yba2cu3o6.70 - Evidence For A Pseudogap”, Phys. Rev. Lett., vol. 71, p. 1645, 1993.
5. D.W. Lynch et al., Photoemission Studies of High-Temperature Superconductors, UK, Cambridge: Cambridge University Press, 2005. 6. H. Ding et al., “Evolution of the Fermi Surface with Carrier Concentration in BiSrCaCuO”, Phys. Rev. Lett., vol. 78, p. 2628, 1997.
7. T. Mamedov and M. de Llano, “Superconducting Pseudogap in a Boson-Fermion Model”, J. Phys. Soc. Japan, vol. 79, p. 044706, 2010.
8. A. Bugrij and V. Loktev, “On the theory of Bose-condensate fluctuations in systems of finite size”, Low Temp. Phys., vol. 35, p. 770, 2009.
9. M. Jia-Wei et al., “Luttinger-volume violating Fermi liquid in the pseudogap phase of the cuprate superconductors”, Phys. Rev. B, vol. 85, p. 134519, 2012.
10. Y.J. Uemura et al., “Universal Correlations Between Tc And Ns/M-Star (Carrier Density Over Effective Mass) In High-Tc Cuprate Superconductors”, Phys. Rev. Lett., vol. 62, p. 2317, 1989.
11. V. Emery and S. Kivelson, “Importance of Phase Fluctuations in Superconductors with Small Superfluid Density”, Nature, vol. 374, p. 434, 1995.
12. P.A. Lee and X.G. Wen, “Theory of underdoped cuprates”, Phys. Rev. Lett., vol. 76, p. 503, 1996.
13. A. Nazarenko et al., “d-wave superconductivity in a model of correlated electrons”, Phys. Rev. B, vol. 54, R768, 1996.
14. N.E. Bickers and D.J. Scalapino, “Conserving Approximations For Strongly Fluctuating Electron-systems.1. Formalism And Calculational Approach”, Ann. Phys. (N.Y.), vol. 193, p. 206, 1989.
15. A.B. Migdal, Theory of Finite Fermi Systems and Applications to Atomic Nuclei. NY: Wiley Interscience, 1967. 16. R. Haussmass, “Properties of a Fermi liquid at the superfluid transition in the crossover region between BCS superconductivity and Bose-Einstein condensation”, Phys. Rev. B, vol. 49, p. 12975, 1994. 17. A. Nazarenko and J. Engelbrecht, “Vortex-pair unbinding in the normal state of two-dimensional short—coherencelength superconductors”, Europhys. Lett., vol. 51, p. 96, 2000. 18. A. Nazarenko and J. Engelbrecht, “Relating pseudogaps and pairing fluctuations in underdoped cuprates”, Physica C, vol. 341, p. 139, 2000.
19. H. Vidberg and J. Serene, “Solving Eliashberg Equations By Means Of N-Point Pade Approximants”, J. Low Temp. Phys., vol. 29, vol. 179, 1977.
20. I. Bariakhtar and A. Nazarenko, “On the Normal State Properties of the 2D Fermi System in Presence of Strong Correlation”, APS March Meeting, R1.276, 2004.
21. J.M. Singer et al., “From BCS-like superconductivity to condensation of local pairs: A numerical study of the attractive Hubbard model”, Phys. Rev. B, vol. 54, p. 1286, 1996.
22. R. dos Santos, “Spin gap and superconductivity in the three-dimensional attractive Hubbard model”, Ibid, vol. 50, p. 635, 1994.
23. M. Randeria et al, “Momentum Distribution Sum-Rule For Angle-Resolved Photoemission”, Phys. Rev. Lett., vol. 74, p. 4951, 1995 [and references therein].
24. A. Nazarenko et al., “Anisotropic Pseudogap in the Normal State of a d-wave Superconductor”, J. Phys. Chem Solids, vol. 59, p. 1745, 1998.
25. Z.-X. Shen and J. R. Schrieffer, “Momentum, Temperature, and Doping Dependence of Photoemission Lineshape and Implications for the Nature of the Pairing Potential in High- Tc Superconducting Materials”, Phys. Rev. Lett., vol. 78, p. 1771, 1997.
26. M. Guidry et al., “Strong anisotropy of cuprate pseudogap correlations: implications for Fermi arcs and Fermi pockets”, New J. Phys., vol. 11, p. 123023, 2009.
27. P.A. Lee and X.G. Wen, “Unusual Superconducting State of Underdoped Cuprates”, Phys. Rev. Lett., vol. 78, p. 4111, 1997.

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