Abstract
We have studied the Raman modes in HgBa2CuO4+δ crystallites through polarized Raman measurements. The Raman peaks at 158 and 592 cm-1 are assigned to be the Ba A1g mode and the O(2) A1g mode respectively. This is in reasonable agreement with the results of LDA total-energy phonon calculations of HgBa2CuO4+δ. To clarify symmetry and site assignment for the mode near 570 cm-1, we studied its behavior at elevated temperatures. Together with a thermogravimetric analysis (TGA), it is found that the 570 cm-1 mode is not related to the O(3) 'interstitial' oxygen as suggested by some authors. However, the polarization dependence of the 570 cm-1 mode shows no conclusive sign of Eg symmetry contrary to our previous speculation.
| Original language | English |
|---|---|
| Pages (from-to) | 35-39 |
| Number of pages | 5 |
| Journal | Physica C: Superconductivity and its Applications |
| Volume | 233 |
| Issue number | 1-2 |
| DOIs | |
| State | Published - 10 Nov 1994 |
Bibliographical note
Funding Information:The results of polarization measurements and Ra-man frequency calculations of F-point Alg phonons allow us to assign the mode at 158 cm-~ to be Ba A~ s and the mode at 592 cm -~ to be 0(2) A~g modes. The peak at 570 cm-~ which was conjectured to be the Es mode of O (2) in our previous paper does not show any conclusive sign of E s symmetry in our polarization measurements. From the results of TGA ISY acknowledges the support from the Basic Science Research Institute Program of the Ministry of Education of Korea under the project number BSRI-94-2428 and the Fund for Research Institute in University, Korea Research Foundation. JY acknowledges the support by KOSEF(931-0200-025-2).