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Magnetization
and Electronic Structure of FeAs Layered Material
(Pemagnetan dan Struktur Elektronik bagi FeAs Berlapis)
Noriza Ahmad Zabidi*, Hasan Abu Kassim
& Keshav N. Shrivastava
Department of Physics, Faculty of Science
University of Malaya, Kuala Lumpur 50603, Malaysia
Diserahkan: 5 Januari 2010 / Diterima: 21 Mei 2010
ABSTRACT
Magnetic induction in the
superconductor (B=H +4πM) in the zero field cooled samples (ZFC)
is not equal to zero. Depending upon the chemical environment it has negative
value in some and positive values in some others. In the field cooled samples,
the magnetization becomes paramagnetic. We have calculated the band structure
of one layer of FeAs lattice with spin polarized as well as unpolarized
orbitals as a function of doping by Li atoms. For n number of Li atoms (n=0,
1,…, 4), we calculated the band gap at all of the k-points as well as the Fermi
energy. The reduced normal state gap was found to lead to superconductivity.
Keywords: Band structure;
energy gap; FeAs; Fermi energy; magnetic induction
ABSTRAK
Aruhan magnet
superkonduktor (B=H +4πM) di dalam sampel sejuk bermedan sifar (ZFC)
tidak sama dengan sifar. Bergantung kepada persekitaran kimia, B mempunyai
nilai negatif di sesetengah dan nilai positif di sesetengah yang lain. Di dalam
sampel sejuk bermedan, pemagnetan menjadi paramagnet. Kami telah mengira
struktur jalur satu lapisan kekisi FeAs dengan menggunakan spin terkutub dan
juga spin tidak terkutub sebagai suatu fungsi pengedopan oleh atom Li. Untuk
bilangan atom Li, n (n=0, 1,…, 4), kami telah menghitung jurang jalur pada
semua titik-k dan juga tenaga Fermi. Jurang keadaan normal yang berkurangan
didapati telah membawa kepada kesuperkonduksian.
Kata kunci: Aruhan
magnet; jurang tenaga; FeAs; struktur jalur; tenaga Fermi
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*Pengarang untuk surat-menyurat; email: nazca_leo@hotmail.com
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