View : 11 Download: 0

Effects of heating on the Raman spectra of YBa2Cu3O7-δ

Title
Effects of heating on the Raman spectra of YBa2Cu3O7-δ
Authors
Yang I.-S.Khim Z.G.
Ewha Authors
양인상
SCOPUS Author ID
양인상scopus
Issue Date
1993
Journal Title
Applied Physics A Solids and Surfaces
ISSN
0721-7250JCR Link
Citation
vol. 57, no. 6, pp. 533 - 538
Publisher
Springer-Verlag
Indexed
SCOPUS scopus
Abstract
We report effects of heating to the intensities of Raman modes in the spectra of single-crystals embedded in ceramic YBa2Cu3O7-δ pellets, and compare the results with those from YBa2Cu3O7-δ thin-films. Heating was done by either increasing the laser-beam power or resistively heating in a heating cell. From the measurements on a single-crystal in z(xx) {Mathematical expression} polarization, we find that the relative intensity of the B1 g mode of the plane oxygens to that of the A1 g mode of apical oxygens decreases strongly as the samples are heated. For a crystal in near x(zz) {Mathematical expression} polarization, the relative intensity of the two modes increases up to certain value. In thin-films, however, no such change was observed even when heated to higher temperatures than the crystals were. Therefore, we interpret that the change in the relative intensity of the two modes of single-crystals is not due to electronic or structural changes nor thermal decomposition in the heated samples. We propose that a single-crystal, when heated, is fractured into many "micro-crystals" and these micro-crystals thermally fluctuate in orientations. For thin-films, such fluctuation in orientations might be hindered because there are only a few layers of micro-crystals on top of the substrate. Scanning electron micrographs (SEM) of the heated part of the samples seem to provide the evidence of the micro-crystals. © 1993 Springer-Verlag.
DOI
10.1007/BF00331754
Appears in Collections:
자연과학대학 > 물리학전공 > Journal papers
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE