Nonlinear Electromechanical Properties of a -quartz

An electrostriction in a-quartz is small. Electrostriction could be demonstrated in the direction of the optical c-axis by the simplest way. Only the electrostrictive deformation is generated by an electric field A3 in this directioa There is a zero piezoelectric coefficient J33 = 0 without an electric field A3 in this direction. The electric field A3 generates piezoelectric coefficient 33 proportional to this electric field. Corresponding component of the electrostrictive coeffieient exhibits the value of 03333 = 3 x 10 m An electric field of the magnitude of 10 Vm must be used to induce the same piezoelectric effect in Z-cut like it is present in X-cut of a-quartz. Substantially higher electrostrietion effeet is observed in some ferroelectric ciystals. 

Elasto-optical coefficient Piezo-optical coefficient  

For the structure of tensor components of the nonlinear material coefficient see Table 7.3. Piezo-optical, elasto-optical and electro-elastic coefficients for a-quartz are listed in Table 7.4. 

There is only one independent piezoelectric coefficient for -quartz. Structure of the piezoelectric tensor components is following 

612°C has been measnred. An average temperature coefficient reaches the value of Tdu = -12.8 X in the temperature range from 585 to 626°C. Newer 

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