Microwave Dielectric Characteristics of $Ba(Mg_{1/3}Nb_{2/3})O_3$ - $La(Mg_{2/3}Nb_{1/3})O_3$ Solid Solutions with Crystal Structure

결정구조에 의한 $Ba(Mg_{1/3}Nb_{2/3})O_3$ - $La(Mg_{2/3}Nb_{1/3})O_3$고용체의 마이크로파 유전 특성

The microwave dielectric properties and their related structural characteristics in solid solutions of (1-x) $Ba(Mg_{1/3}Nb_{2/3})O_3$ -x $La(Mg_{2/3}Nb_{1/3})O_3$ (BLMN) have been investigated by measuring the dielectric constant${\varepsilon}r)$, Q value and temperature coefficient of resonant frequency$({\tau}f)$ and by observing the crystal structure using high resolution transmission electron microscopy (HRTEM). Microwave dielectric properties showed characteristic features for specific composition. Dielectric constant$({\varepsilon}r)$ showed maximum value at the composition which corresponds to the phase boundary between 1:2 ordered and 1:1 ordered structure. The increase in ${\varepsilon}_r$ may be caused by the rattling of ions by incorporating smaller ions and the disordered structure. The variation of temperature coefficient of resonant frequency${{\tau}_f)$ was investigated in terms of oxygen octahedra tilting.