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

T. Jarlborg

doi:10.1016/j.ssc.2013.11.030

paper

Theoretical aspects of simple and nested Fermi surfaces for superconductivity in doped semiconductors and high- $T_{C}$ cuprates

arXiv:1312.6605 · doi:10.1016/j.ssc.2013.11.030

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 $λ$ 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 $N (E_{F})$ .

5 pages, 5 figures

Theoretical aspects of simple and nested Fermi surfaces for superconductivity in doped semiconductors and high- $T_{C}$ cuprates

Abstract

References in corpus (8)

Cited by in corpus (2)

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

Abstract

References in corpus (8)

Cited by in corpus (2)

Theoretical aspects of simple and nested Fermi surfaces for superconductivity in doped semiconductors and high- $T_{C}$ cuprates