Growth, electromechanical, and electro-optic properties of tungsten bronze (Ca0.28Ba0.72)0.25(Sr0.6Ba0.4)0.75Nb2O6 single crystal

A calcium strontium barium niobate (Ca(0.28)Ba(0.72))(0.25)(Sr(0.60)Ba(0.40))(0.75)Nb(2)O(6) (CSBN25) single crystal has been grown using the Czochralski technique. The point group and space group of CSBN25 were determined by x-ray powder diffraction analysis to be tetragonal 4 mm and P4bm, respectively. The complete set of dielectric, piezoelectric, and elastic constants of CSBN25 have been determined by resonance techniques and impedance analysis at room temperature, and the relevant constants have been obtained and discussed. The relative dielectric constants are epsilon(11) = 343, and epsilon(33)= 502. Our results show that CSBN25 has excellent piezoelectric properties with d(33)=94.3, d(31)=-31.1, and d(15)= 16.6 pC/N. The elastic compliance constants are s(11)=5.1, s(12)=-4, s(13)=1.4, s(33)=5.1, s(55)=13.2, and s(66)=19 pm(2)/N. The linear electro-optic coefficients of CSBN25 also have been measured by using an interferometric method. The results obtained are gamma(33)=140, gamma(13)=18, gamma(51)=18, and gamma(c)=108.7 pm/V. (C) 2010 American Institute of Physics.