Related Experiment Video
Updated: Feb 8, 2026

Preparation of Macroporous Epitaxial Quartz Films on Silicon by Chemical Solution Deposition
Published on: December 21, 2015
Quartz-Enhanced Photoacoustic Spectroscopy Sensor with a Small-Gap Quartz Tuning Fork
Yu-Fei Ma1, Yao Tong2, Ying He3
1National Key Laboratory of Science and Technology on Tunable Laser, Harbin Institute of Technology, Harbin 150001, China. mayufei@hit.edu.cn.
Abstract:
A highly sensitive quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor based on a custom quartz tuning fork (QTF) with a small-gap of 200 μm was demonstrated. With the help of the finite element modeling (FEM) simulation software COMSOL, the change tendency of the QEPAS signal under the influence of the laser beam vertical position and the length of the micro-resonator (mR) were calculated theoretically. Water vapor (H₂O) was selected as the target analyte. The experimental results agreed well with those of the simulation, which verified the correctness of the theoretical model. An 11-fold signal enhancement was achieved with the addition of an mR with an optimal length of 5 mm in comparison to the bare QTF. Finally, the H₂O-QEPAS sensor, which was based on a small-gap QTF, achieved a minimum detection limit (MDL) of 1.3 ppm, indicating an improvement of the sensor performance when compared to the standard QTF that has a gap of 300 μm.
More Related Videos
Related Concept Videos
The DNA Replication Fork
The DNA Replication Fork
Restarting Stalled Replication Forks
Restarting Stalled Replication Forks
Gap Junctions
Gap Junctions

