Electrostatic measurements of unusually large secondary pyroelectricity in partially clamped LiNbO3

Abstract

Pyroeleetricity has been observed in single domain, single crystal LiNbO3 under partially clamped elastic boundary conditions using a non-contact electrostatic voltmeter. These boundary conditions were produced by the use of localized laser heating which generated a temperature change in the central 2.5 mm of a 19 mm diameter disk. These partially clamped boundary conditions give rise to (1) unusually large secondary pyroelectric effect in 2-cut crystals (the 2 or y axis perpendicular to the disk's face) whose components along the 1 and 3 axes map the radial and tengential components of the thermal stress, respectively and (2) surface and volume polarization which permit a partial experimental separation of primary and secondary pyroelectricity.