ISSN:
1572-9605
Keywords:
pairing mechanism
;
transition temperature
;
isotope effect
;
cuprates
Source:
Springer Online Journal Archives 1860-2000
Topics:
Electrical Engineering, Measurement and Control Technology
,
Physics
Notes:
Abstract An effective two-dimensional dynamic interaction is developed which incorporates screening of holes by plasmons and by optical phonons to discuss the nature of the pairing mechanism leading to superconductivity in layered mercury cuprates. The system is treated as an ionic solid containing layers of charge carriers and a model dielectric function is set up which fulfils the appropriate sum rules on the electronic and ionic polarizabilities. The static limit of the model dielectric function is used to calculate the effective hole-hole coupling strength. The values of the electron-phonon coupling strength and of the Coulomb interaction parameter indicate that the superconductor is in the strong coupling regime with effective screening of the charge carriers. The superconducting transition temperature of optimally doped HgBa2CuO4+δ is estimated as 120 K from Kresin's strong coupling theory and the energy gap ratio is substantially larger than the BCS value. The value of the isotope exponent is severely reduced below the BCS value. The implications of the model and its analysis are discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1007829018708
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