|
NISCAIR ONLINE PERIODICALS REPOSITORY (NOPR) >
NISCAIR PUBLICATIONS >
Research Journals >
Indian Journal of Pure & Applied Physics (IJPAP) >
IJPAP Vol.49 [2011] >
IJPAP Vol.49(01) [January 2011] >
| Title: | Field dependent specific heat of PbTiO3 and KNbO3 ferroelectric perovskites |
| Authors: | Singh, Talvinder
Kumar, Ashok
Naithani, U C |
| Keywords: | Specific heat
Ferroelectric perovskites
Anharmonicity
Green’s function
Soft mode |
| Issue Date: | Jan-2011 |
| Publisher: | NISCAIR-CSIR, India |
| Abstract: | An
expression has been obtained for the specific heat of anharmonic pure PbTiO3
and KNbO3 ferroelectric perovskites using double-time Green’s
function along with Silverman-Joseph modified Hamiltonian which includes
anharmonicity up to the fourth order due to the interaction of the soft mode.
The electric field and temperature dependence of the soft mode and the specific
heat has been studied for both the crystals. The specific heat decreases with
increasing external electric field and increases with increasing temperature.
In the low field’s region, the effect of temperature ceases and the change in
specific heat arises mainly due to higher order anharmonic terms. Anharmonicity
is necessary in these crystals to observe these effects. |
| Page(s): | 59-63 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-1041 (Online); 0019-5596 (Print) |
| Source: | IJPAP Vol.49(01) [January 2011]
|
|
