UNIGE document Scientific Article
previous document  unige:35457  next document
add to browser collection
Title

Theoretical aspects of simple and nested Fermi surfaces for superconductivity in doped semiconductors and high-TC cuprates

Author
Published in Solid State Communications. 2014, vol. 181, p. 15-19
Abstract The density-of-states at the Fermi energy, $N(E_F)$, is low in doped superconducting semiconductors and high-$T_C$ cuprates. This contrasts with the common view that superconductivity requires a large electron-boson coupling $lambda$ and therefore also a large $N(E_F)$. However, the generic Fermi surfaces (FS) of these systems are relatively simple. Here is presented arguments showing that going from a 3-dimensional multi-band FS to a 2-dimensional and simple FS is energetically favorable to superconductivity. Nesting and few excitations of bosons compensate for a low $N(E_F)$. The typical behavior of the 2-dimensional FS for cuprates, and small 3-dimensional FS pockets in doped semiconductors and diamond, leads to $T_C$ variations as a function of doping in line with what has been observed. Diamond is predicted to attain higher $T_C$ from electron doping than from hole doping, while conditions for superconductivity in Si and Ge are less favorable. A high-$T_C$ material should ideally have few flat and parallel FS sheets with a reasonably large $N(E_F)$.
Identifiers
Full text
Article (Published version) (470 Kb) - document accessible for UNIGE members only Limited access to UNIGE
Structures
Research group Groupe Giamarchi
Citation
(ISO format)
JARLBORG, Thomas N. Theoretical aspects of simple and nested Fermi surfaces for superconductivity in doped semiconductors and high-TC cuprates. In: Solid State Communications, 2014, vol. 181, p. 15-19. https://archive-ouverte.unige.ch/unige:35457

467 hits

0 download

Update

Deposited on : 2014-04-08

Export document
Format :
Citation style :