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

Area of Science:

• Materials Science
• Physics
• Engineering

Background:

• Accurate detection of low-frequency vibrations is crucial for various applications.
• Existing sensors may struggle with sub-nanometer amplitudes or harsh environmental conditions.

Purpose of the Study:

• To develop and characterize a novel low-frequency vibration sensor.
• To evaluate the sensor's sensitivity and detection limits for sub-nanometer vibrations.

Main Methods:

• Utilized a cantilever made of a single-crystalline lithium niobate (LiNbO₃) plate with a bidomain ferroelectric structure.
• Measured sensor response to sinusoidal vibrational excitations in terms of displacement and acceleration amplitude.
• Analyzed sensor sensitivity and smallest detectable vibration across a frequency range up to 150 Hz.

Main Results:

• Demonstrated linear sensor response to vibrational displacement amplitude up to 150 Hz.
• Achieved sensitivities ranging from 20 μV/nm to 92.5 mV/nm and 7 V/g to 2443 V/g.
• Showcased smallest detectable vibrations varying from 100 nm at 7 Hz to 0.1 nm above 38 Hz.

Conclusions:

• The developed LiNbO₃ cantilever sensor effectively detects ultra-weak, low-frequency vibrations.
• Bidomain lithium niobate single crystals are promising sensitive elements for vibration detection in demanding conditions.
• The sensor exhibits potential for applications requiring high sensitivity across a wide temperature range.