Dielectric dispersion and piezoelectric resonance in benzil single crystals grown by Bridgman-Stockbarger technique

M V Shankar, K B R Varma
1996 Bulletin of Materials Science  
Large single crystals of an organic nonlinear optical (NLO) material, benzil, have been grown by employing an indigenously built Bridgman-Stockbarger crystal growth system. The dielectric constant (c r ), dielectric loss tangent (tan 5) and impedance (Z) of these crystals, monitored along the crystallographic a-axis, as a function of frequency in the IQOkHz-lOMHz range, exhibit sharp resonance effects in the 100-300kHz region. These strong resonance effects are attributed to the piezoelectric
more » ... the piezoelectric nature of the crystal. The origin of the appearance of the sharp peaks in the frequency variation of t; r and tan S is in response tô the elastic resonances induced via the externally applied electric field. The resonance peak f positions shift towards lower frequencies with increase in temperature as a consequence of the decrease in the stiffness coefficient (C") of the crystal.
doi:10.1007/bf02745199 fatcat:pdeapdf5xzfv3j5rs4udypuada