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IJPAP Vol.46 [2008] >
IJPAP Vol.46(08) [August 2008] >
| Title: | Electric field dependent microwave losses in BaxSr₁₋xTiO₃ perovskites |
| Authors: | Kukreti, Ashish
Kumar, Ashok
Naithani, U C |
| Keywords: | Anharmonicity
Softmode
Microwave loss tangent
Displacive ferroelectrics |
| Issue Date: | Aug-2008 |
| Publisher: | CSIR |
| Abstract: | The electric field dependent microwave loss of anharmonic BaxSr₁₋xTiO₃ perovskites has been calculated in its para electric phase from the Silverman Joseph Hamiltonoian augumented with fourth order phonon co-ordinates using double time Greens functions. The results are used to obtain an expression for the frequency and temperature dependence of dielectric loss at microwave frequencies due to impurity and anharmonic scattering. The loss tangent consists of a contribution which is quadratic in applied biasing and field independent. The variation of tan δ with applied field is noticeable in the vicinity of Curie temperature . In the higher temperature region, the electric field effect ceases and the increase in loss arises mainly due to higher order anharmonic terms. |
| Page(s): | 580-587 |
| ISSN: | 0019-5596 |
| Source: | IJPAP Vol.46(08) [August 2008]
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