Vibrations of Periodically Poled Lithium Niobate Bar with 0.3-mm Long Domains

TL;DR

This study investigates the three-dimensional vibrations in periodically poled Lithium Niobate bars with 0.3-mm domains, analyzing excitation methods and validating theoretical models with experimental data.

Contribution

It provides a detailed computational analysis of vibrations in periodically poled Lithium Niobate, including experimental validation of the acoustic response.

Findings

Vibrations can be excited by longitudinal acousto-electric current and transverse electric fields.

Theoretical computations match experimental admittance measurements.

Peak positions in admittance correlate with maximum acoustic amplitudes.

Abstract

The three dimensional vibrations in a periodically poled ZX-cut Lithium Niobate thin bar with 0.3-mm long domains are considered. The acoustical vibrations may be excited by the 1) longitudinal acousto-electric current when a radio frequency voltage is parallel to the x-axis, and 2) transverse electric field when a radio frequency voltage is parallel to the z-axis. The computations by the Final Element Method reveal all the three displacements along the x, y, and z crystallographic axes. The amplitudes may be different for two types of vibration excitations. The positions of peaks in admittance versus frequency correlate with the frequencies of maximum acoustic amplitudes. The superlattice with 0.3-mm long domains along the x-axis is fabricated in the z-cut 0.5-mm-thick wafer. The experimental data on the radio frequency admittance versus frequency is in agreement with the corresponding theoretical computations.