National Changhua University of Education Institutional Repository : Item 987654321/14106

English | 正體中文 | 简体中文 | Items with full text/Total items : 6507/11669
Visitors : 30055313 Online Users : 639

RC Version 3.2 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.

Scope Adv. Search

Login ‧ Upload ‧ Help ‧ About ‧ Administer

NCUEIR > College of Science > Department of Physics > Periodical Articles > Item 987654321/14106

Please use this identifier to cite or link to this item: http://ir.ncue.edu.tw/ir/handle/987654321/14106

Title:	Evolution of Optical Absorption and Superconductivity in Bi-2212 and 2223 Oxides Intercalated by Metal-phthalocyanines: A Systematical Study as a Function of Intercalation Level
Authors:	Grigoryan, L.;Yalushi, K.;Liu, Chia-Jyi;Takano, S.;Walata, M.;Yamauchi, H.
Contributors:	物理學系
Date:	1993-12
Issue Date:	2012-09-10T06:11:26Z
Publisher:	Elsevier
Abstract:	Exposure to vapors of the metal-phthalocyanines MPc (M = Zn, Ni, Fe or Pb) brings about a systematical variation of optical and superconducting properties of Bi-2212 and 2223 high-Tc oxides. With increasing level of MPc uptake, the spectral weight is gradually transferred from the low to the high-frequency regions, accompanied by a decrease of Tc, diamagnetic response and magnetic hysteresis. Two different types of evolution patterns were observed: the first was characterized by a sharp change at the lowest level of MPc uptake (Tc, hysteresis), while the second featured a gradual evolution (intensities of the electronic absorption bands, diamagnetism). The heavily intercalated Bi-oxides are brightly colored non-conducting materials with well-resolved vibrational features due to both the intercalated MPc molecules and the host oxides. The above evolution patterns are ascribed to a combination of two mechanisms: the decrease of the charge carrier concentration as a result of electron doping into the host oxide, and the increase of anisotropy of the system due to incorporation of insulating MPc molecular layer between the Bi-O bilayers, thereby reducing the coupling along the c-axis. Hence, the intercalation by MPc is shown to be an effective technique for the electron doping leading to a reduction of the charge carrier concentration in the host oxides, in contrast to the intercalation by iodine which leads to a hole doping and to an increase of the number of charge carriers.
Relation:	Physica C: Superconductivity, 218(1-2): 153-163
Appears in Collections:	[Department of Physics] Periodical Articles

Files in This Item:

File	Size	Format
2020200410056.pdf	7Kb	Adobe PDF	444	View/Open

Loading...