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Title: A Room Temperature Compensated Lateral Field Excited Lithium Tantalate Sensor Platform
The quartz crystal monitor (QCM) is a common sensor platform based on the room temperature compensated pure shear mode (PSM) of thickness field excited (TFE) AT-cut quartz. However, with electrodes on both crystal faces, TFE only allows sensing of mechanical property changes. Lateral field excitation (LFE), where both electrodes are on a single face, enables the detection of both mechanical and electrical changes, potentially leading to higher sensitivity. As lithium tantalate (LT) has an LFE PSM and piezoelectric coupling several times greater than that of quartz, LFE LT was chosen as a possible replacement for TFE quartz. A theoretical search of all LT cuts identified those exhibiting a room temperature compensated PSM. A set of orientations ranging from (YXwl) 0°/-85° to 0°/-90° was chosen for experimental verification. The temperature response of each sample was shown to be parabolic, with a roughly linear relationship between crystal cut angle and temperature inflection point/turnaround temperature. Specifically, the (YXwl) 0°/-87° cut with a turnaround temperature at 26.4°C demonstrates that a room temperature PSM in LT can be excited via LFE. Future work focusing on the development of an LT sensing platform could profoundly impact sensor systems in agriculture, homeland security, global warming, and medical applications.  more » « less
Award ID(s):
1851998
PAR ID:
10482388
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
IEEE
Date Published:
Journal Name:
2023 IEEE International Ultrasonics Symposium (IUS)
ISBN:
979-8-3503-4645-9
Page Range / eLocation ID:
1 to 4
Format(s):
Medium: X
Location:
Montreal, QC, Canada
Sponsoring Org:
National Science Foundation
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