Piezoelectrically stimulated dielectric dispersion in KAP single crystals

Shankar, MV and Varma, KBR (1997) Piezoelectrically stimulated dielectric dispersion in KAP single crystals. In: Materials Chemistry and Physics, 49 (1). pp. 78-82.

PDF Piezoelectrically_stimulated_dielectric.pdf - Published Version Restricted to Registered users only Download (497kB) | Request a copy

Abstract

The frequency response of the dielectric constant (epsilon(r)), the loss tangent (tan delta) and impedance Z of potassium acid phthalate (KAP) single crystals, monitored along the polar axis, exhibit strong resonances in the frequency range 50-200 kHz, depending on the dimensions of the sample. The observed resonance effect, which is strongly dependent on the geometric shape and size of the sample, is attributed to its piezoelectric nature. The resonance peak positions have been monitored as a function of both temperature and uniaxial pressure. The stiffness coefficient (C), computed based on the resonance data, is found to decrease with increasing temperature and increase with increasing pressure. The electro-mechanical coupling coefficient (k), obtained by resonance-anti-resonance method, has also been found to increase with rise in temperature. The epsilon(r) behaviour along the polar axis, as a function of temperature is consistent with that of k. The preliminary results on the influence, of partial replacement of K+ ions in the KAP crystal by Cs+ and Li+ ions, on the observed piezoelectric resonance effects are also included.

Item Type:	Journal Article
Publication:	Materials Chemistry and Physics
Publisher:	Elsevier Science
Additional Information:	Copyright of this article belongs to Elsevier Science.
Keywords:	Dielectric dispersion;Piezoelectric resonance;Potassium acid phthalate
Department/Centre:	Division of Chemical Sciences > Materials Research Centre
Date Deposited:	30 Jun 2011 14:17
Last Modified:	30 Jun 2011 14:17
URI:	http://eprints.iisc.ac.in/id/eprint/38356

Actions (login required)

View Item