Microwave losses in incipient ferroelectrics as functions of the temperature and the biasing field

The dielectric constant of ferroelectric materials can be controlled by an applied electric field. That is promising for applications using the microwave technique. The widespread use of ferroelectric materials at microwaves is retarded by a considerable high dielectric loss by the materials at high frequencies. The goal of this article is to model the essential mechanisms of losses in incipient ferroelectrics at microwave frequencies. The following materials are studied: strontium titanate (SrTiO3) and potassium tantalate (KTaO3). The following loss mechanisms are considered: fundamental loss determined by multiphonon scattering of the soft ferroelectric mode and transformation of microwave electric field oscillations into acoustic oscillations due to residual ferroelectric polarization.

[1]  O. G. Vendik,et al.  Dielectric nonlinearity of the displacive ferroelectrics at UHF , 1976 .

[2]  Spartak Gevorgian,et al.  Electrically Controlled HTSC/Ferroelectric Coplanar Waveguide , 1994 .

[3]  H. Uwe,et al.  Stress-induced ferroelectricity and soft phonon modes in SrTi O 3 , 1976 .

[4]  O. Vendik,et al.  Modeling the dielectric response of incipient ferroelectrics , 1997 .

[5]  W. R. Abel.  Effect of Pressure on the Static Dielectric Constant of KTaO3 , 1971 .

[6]  G. V. Belokopytov.  Low-temperature nonlinear microwave response of incipient ferroelectrics , 1995 .

[7]  Q. X. Jia,et al.  Electrically tunable coplanar transmission line resonators using YBa2Cu3O7−x/SrTiO3 bilayers , 1995 .

[8]  R. O. Bell,et al.  MICROWAVE LOSSES IN STRONTIUM TITANATE ABOVE THE PHASE TRANSITION , 1962 .

[9]  F. Lytle.  X‐Ray Diffractometry of Low‐Temperature Phase Transformations in Strontium Titanate , 1964 .

[10]  G. Shirane,et al.  Anomalous Acoustic Dispersion in Centrosymmetric Crystals with Soft Optic Phonons , 1970 .

[11]  G. Shirane,et al.  Study of Critical Fluctuations in BaTi O 3 by Neutron Scattering , 1969 .

[12]  O. Vendik,et al.  High-T c superconductivity: New applications of ferroelectrics at microwave frequencies , 1993 .

[13]  A. Dedyk,et al.  The dielectric hysteresis of YBCO-SrTiO3-YBCO structures at 4.2 K , 1993 .

[14]  S. Gevorgian,et al.  1 GHz tunable resonator on bulk single crystal SrTiO3 plated with YBa2Cu3O7-x films , 1995 .