Low-Frequency Vibration Sensor with a Sub-nm Sensitivity Using a Bidomain Lithium Niobate Crystal

Abstract

We present a low-frequency sensor for the detection of vibrations, with a sub-nm amplitude, based on a cantilever made of a single-crystalline lithium niobate (LiNbO3) plate, with a bidomain ferroelectric structure. The sensitivity of the sensor-to-sinusoidal vibrational excitations was measured in terms of displacement as well as of acceleration amplitude. We show a linear behavior of the response, with the vibrational displacement amplitude in the entire studied frequency range up to 150 Hz. The sensitivity of the developed sensor varies from minimum values of 20 μV/nm and 7 V/g (where g = 9.81 m/s2 is the gravitational acceleration), at a frequency of 23 Hz, to peak values of 92.5 mV/nm and 2443 V/g, at the mechanical resonance of the cantilever at 97.25 Hz. The smallest detectable vibration depended on the excitation frequency and varied from 100 nm, at 7 Hz, to 0.1 nm, at frequencies above 38 Hz. Sensors using bidomain lithium niobate single crystals, as sensitive elements, are promising for the detection of ultra-weak low-frequency vibrations in a wide temperature range and in harsh environments.

Self-Biased Bidomain LiNbO3/Ni/Metglas Magnetoelectric Current Sensor

“…An additional advantage of lithium niobate crystals is the absence of a lead component in their composition. As is known, the bidomain LN crystals demonstrated excellent properties in the application of magnetoelectric (ME) magnetic sensors [ 43 , 47 ], vibration sensors [ 48 ] and energy harvesters [ 49 ].…”

Magnetoelectric Effect in the Bidomain Lithium Niobate/Nickel/Metglas Gradient Structure

“…Recently we reported the advantages of ME sensors based on bidomain lithium niobate (LN) crystals over those based on PZT or PMN‐PT and showed that the bidomain LN is very promising for applications such as sensing of weak and low‐frequency magnetic fields, energy harvesting, and detection of sub‐nanometer vibrations …”

“…Recently we reported the advantages of ME sensors based on bidomain lithium niobate (LN) crystals over those based on PZT or PMN-PT [21] and showed that the bidomain LN is very promising for applications such as sensing of weak and low-frequency magnetic fields, energy harvesting, [22][23][24] and detection of subnanometer vibrations. [25,26] The paper describes the ME effect in a gradient laminate structure consisting of a bidomain LiNbO 3 /Ni/metglas trilayer. The structure comprises a bidomain LN single crystal with a Y þ 128 cut.…”

Use of Ferroelectric Single-crystal Bimorphs for Precise Positioning in Scanning Probe Microscope

“…To the best of our knowledge, among the variety of ferroelectrics only two materialslithium niobate (LiNbO3) and lithium tantalate (LiTaO3)can be stable in a bidomain state due to their uniaxial domain structure and high coercive field [3]. Previously the possibility to use bidomain single crystals in linear actuators and deflectors [4,5], vibrational [2] and magnetic field [6] sensors as well as waste energy harvesters [7,8] has been shown. In this study, we present the use of ferroelectric single-crystal bimorphs for precise positioning in a scanning probe microscope.…”

“…Despite this fact, the main disadvantage of single-crystal piezoelectricssmall piezoelectric coefficientsis the reason why PZT is still used in most cases. The problem of the weak conversion of a mechanical deformation into an electrical signal by single-crystal piezoelectric materials can be solved by utilizing complex constructions, such as unimorphs, bimorphs, or multilayer composites, but the presence of adhesive layers or grain boundaries in these composite transducers decreases the sensitivity, as well as the accuracy and thermal stability of the sensors [2]. However, there is a way to manufacture a series bimorph for the piezoelectric sensing element and avoid bonding of separate plates by the formation of two domains with oppositely directed spontaneous polarization vectors in a ferroelectric single-crystal plate.…”