2 / 28
Page 18
Notes:
allied
academies
Journal of Materials Science and Nanotechnology | Volume: 2
August 20-21, 2018 | Paris, France
Materials Science and Materials Chemistry
International Conference on
Antiferromagneticallyassistedelectron-phononcouplingasamechanismof Fe-basedsuperconductivity
Wong Chi Ho
and
Rolf Lortz
Hong Kong University of Science and Technology, Hong Kong
W
hile there is still no self-consistent theory on the
mechanism in iron-based superconductors, we develop
a novel theoretical ab-initio approach that allows us to explicitly
calculate the superconducting transition temperatures (Tc)
of LaFeAsO
1-x
F
x
, SmFeAsO
1-x
F
x
and NdFeAsO
1-x
Fx that perfectly
agree with experiments. We consider recent evidence
that electron-phonon coupling may have been previously
underestimated where the hidden force owing to anti-
ferromagnetism can greatly enhance the electron-phonon
coupling through the localized orbitals of iron d-like xz or yz
orbitals. We then include the contribution of these localized
orbitals in aMcMillan formalismwithmodified pairing potential
that additionally considered the dipole-dipole attraction
between the spin-polarized electrons on the Fermi surface and
the iron orbitals in combinationwith the exchange Hamiltonian.
With this approach we can not only calculate a theoretical Tc
of LaFeAsO
0.9
F
0.1
as a series of pressure corresponding to the
experimentalvalues,butalsogetthecorrectdopingdependence.
Speaker Biography
Wong Chi Ho studied bachelor program in Department of Applied Physics in the Hong
Kong Polytechnic University from 2009 to 2011. In 2010, he went to United Kingdom
as a research trainee (particle physics) in Lancaster University. In 2011, he obtained full
PhD scholarship from Hong Kong. In 2015, he has completed his PhD degree in the field
of experimental and computational superconductivity at the age of 28 years from Hong
Kong University of Science and Technology. In 2016, he was a postdoctoral researcher in
Ural Federal University in Russia. Nowhe returns to Hong Kong to serves as postdoctoral
researcher inHongKongUniversityofScienceandTechnology.Heregisteredtwopatents
in China Patent Office and published many high-impacted journals such as ACS Nano.
e:
on4166@rice.edu