Ab Initio Studies On Superconductivity In Alkali-doped Fullerides (springer Theses)
by Yusuke Nomura /
2016 / English / PDF
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This book covers high-transition temperature
(
This book covers high-transition temperature
(T
Tc
c)
)s
s-wave superconductivity and the
neighboring Mott insulating phase in alkali-doped fullerides. The
author presents (1) a unified theoretical description of the
phase diagram and (2) a nonempirical calculation of
-wave superconductivity and the
neighboring Mott insulating phase in alkali-doped fullerides. The
author presents (1) a unified theoretical description of the
phase diagram and (2) a nonempirical calculation ofT
Tc
c. For these purposes, the author employs an
extension of the DFT+DMFT (density-functional theory + dynamical
mean-field theory). He constructs a realistic
electron–phonon-coupled Hamiltonian with a newly formulated
downfolding method. The Hamiltonian is analyzed by means of the
extended DMFT. A notable aspect of the approach is that it
requires only the crystal structure as a priori knowledge.
. For these purposes, the author employs an
extension of the DFT+DMFT (density-functional theory + dynamical
mean-field theory). He constructs a realistic
electron–phonon-coupled Hamiltonian with a newly formulated
downfolding method. The Hamiltonian is analyzed by means of the
extended DMFT. A notable aspect of the approach is that it
requires only the crystal structure as a priori knowledge.
Remarkably, the nonempirical calculation achieves for the first
time a quantitative reproduction of the experimental phase
diagram including the superconductivity and the Mott phase. The
calculated
Remarkably, the nonempirical calculation achieves for the first
time a quantitative reproduction of the experimental phase
diagram including the superconductivity and the Mott phase. The
calculatedT
Tc
c agrees well with the experimental
data, with the difference within 10 K.
agrees well with the experimental
data, with the difference within 10 K.
The book provides details of the computational scheme, which can
also be applied to other superconductors and other phonon-related
topics. The author clearly describes a superconducting mechanism
where the Coulomb and electron–phonon interactions show an
unusual cooperation in the superconductivity thanks to the
Jahn–Teller nature of the phonons.
The book provides details of the computational scheme, which can
also be applied to other superconductors and other phonon-related
topics. The author clearly describes a superconducting mechanism
where the Coulomb and electron–phonon interactions show an
unusual cooperation in the superconductivity thanks to the
Jahn–Teller nature of the phonons.