Theory of Superconductivity

Many properties of optimally doped High T_c Superconductors are described using an Eliashberg Theory which has been modified for d-wave superconductivity.The required charge carrier-exchange phonon spectral density is derived phenomenologically from the optical scattering rate in the far infrared. At low temperatures the data show in optimally doped YBa₂Cu₃O_6.95 a clear indication of a coupling of the charge carriers to the 41 meV spin resonance.Excellent agreement with experimental data is found for the systems YBCO, Bi2212, Y124, and Tl2201.

Recent Papers:

• J.P. Carbotte and E. Schachinger
  Optical spectral weight distribution in d-wave superconductors
  Phys. Rev. B 69, 224501 (2004). (pdf).
• E. Schachinger, J.J. Tu, and J.P. Carbotte
  Angle-resolved photoemission spectroscopy and optical renormalizations: Phonons or spin fluctuations
  Phys. Rev. B 67, 214508 (2003). (pdf).
• E. Schachinger and J.P. Carbotte
  Residual absorption at zero temperature in d-wave superconductors
  Phys. Rev. B 67, 134509 (2003). (pdf).
• E. Schachinger and J.P. Carbotte
  Extended Eliashberg Theory for d-Wave Superconductivity and Application to Cuprates
  Review article, J. Phys. Stud. 7, 209-233 (2003). (pdf).
• E. Schachinger and J.P. Carbotte
  Microwave Conductivity of YBa₂Cu₃O_6.99 Including Inelastic Scattering
  Phys. Rev. B. 65, 064514 (2002). (pdf).
• F. Marsiglio, J.P. Carbotte, and E. Schachinger
  Sum Rule for Optical Scattering Rates
  Phys. Rev. B. 65, 014515 (2002). (pdf).
• E. Schachinger and J.P. Carbotte
  Signatures of spin degrees of freedom in charge dynamics of YBa₂Cu₃O_6.95
  Physica C 364-365, 13-16 (2001). (pdf).
• E. Schachinger, J.P. Carbotte, and D.N. Basov
  Magnetic resonance at 41 meV and charge dynamics in YBa₂Cu₃O_9.65
  Europhys. Lett. 54, 380-386 (2001) (pdf).
• E. Schachinger and J.P. Carbotte
  Comparison of the in- and out-of-plane charge dynamics in YBa₂Cu₃O_6.95
  Phys. Rev. B 64, 094501 (2001) (pdf).
• E. Schachinger and J.P. Carbotte
  Coupling to spin fluctuations from conductivity scattering rates
  Phys. Rev. B 62, 9054 - 9058 (2000) (pdf).

Analysis of experimental data found in the borocarbides YNi₂B₂C and LuNi₂B₂C using Eliashberg theory revealed that these materials are anisotropic electron-phonon superconductors. The same holds for the new superconductor MgB₂.

Recent Papers:

• M. Zehetmayer, H.W. Weber, and E. Schachinger
  Separable Model Calculations for the Anisotropic Properties of MgB
  J. Low Temp. Phys. 133, 407 (2003). (pdf).
• S. Manalo, M. Michor, M. El-Hagary, G. Hilscher, and E. Schachinger
  Superconducting properties of Y_xLu_1-xNi₂B₂C and La₃Ni₂B₂N_3-d: A comparison between experiment and Eliashberg theory
  Phys. Ref. B 63, 104508 (2001) (pdf).
• S. Manalo and E. Schachinger
  Optimal spectrum for the Borocarbides YNi₂B₂C and LuNi₂B₂C
  J. Low Temp. Phys. 123, 149 - 163 (2001) (pdf).