A new kind of laser microphone using high sensitivity pulsed laser vibrometer

AbstractBulk Ca2RuO4 is an antiferromagnetic Mott insulator with the metal-insulator transition above room temperature, and the Neel temperature at 113 K. There is strong coupling between crystal structures and magnetic, electronic phase transitions in this system. It exhibits high sensitivity to chemical doping and pressure that makes it very interesting material to study. We have epitaxially grown Ca2RuO4 thin films on LaAlO3 substrates by pulsed laser deposition technique. Growth conditions such as substrate temperature and O2 pressure were systematically varied in order to achieve high quality single-phase film. Crystalline quality and orientation of these films were characterized by X-ray diffractometry. Microstructure of the thin films was examined by transmission electron microscopy. The electrical transport properties were also measured and compared with bulk single crystal.

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Flexible and Highly Sensitive Strain Sensor Based on Laser-Induced Graphene Pattern Fabricated by 355 nm Pulsed Laser

Sensors ◽

10.3390/s19224867 ◽

2019 ◽

Vol 19 (22) ◽

pp. 4867 ◽

Cited By ~ 5

Author(s):

Sung-Yeob Jeong ◽

Yong-Won MA ◽

Jun-Uk Lee ◽

Gyeong-Ju Je ◽

Bo-sung Shin

Keyword(s):

Focal Length ◽

Pulsed Laser ◽

Strain Sensor ◽

High Sensitivity ◽

Gauge Factor ◽

Functional Evaluation ◽

Mechanical Fracture ◽

Highly Sensitive ◽

Human Finger ◽

Small Deformations

A laser-induced-graphene (LIG) pattern fabricated using a 355 nm pulsed laser was applied to a strain sensor. Structural analysis and functional evaluation of the LIG strain sensor were performed by Raman spectroscopy, scanning electron microscopy (SEM) imaging, and electrical–mechanical coupled testing. The electrical characteristics of the sensor with respect to laser fluence and focal length were evaluated. The sensor responded sensitively to small deformations, had a high gauge factor of ~160, and underwent mechanical fracture at 30% tensile strain. In addition, we have applied the LIG sensor, which has high sensitivity, a simple manufacturing process, and good durability, to human finger motion monitoring.

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Pyramidal Nanostructures of Zinc Oxide

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2006.17912 ◽

2006 ◽

Vol 6 (1) ◽

pp. 101-104 ◽

Cited By ~ 6

Author(s):

S. Angappane ◽

Neena Susan John ◽

G. U. Kulkarni

Keyword(s):

Zinc Oxide ◽

Growth Habit ◽

Pulsed Laser ◽

High Sensitivity ◽

Laser Deposition ◽

Zno Nanostructures ◽

Force Microscopy ◽

Atomic Force ◽

Oxygen Gas ◽

Hexagonal Nanorods

Zinc oxide (ZnO) nanostructures have been prepared by pulsed laser deposition of the oxide onto Si(100) substrate at 600 °C. An examination of the morphology using atomic force microscopy and scanning electron microscopy reveals well formed pyramidal structures consistent with the growth habit of ZnO. A domain matched epitaxy across the interface makes the ZnO pyramids orient along the axes of Si(100) surface. The pyramidal nanostructures signify an intermediate state in the growth of hexagonal nanorods of ZnO. The hardness of the nanostructures as well as their response to oxygen gas have been investigated using nanoindentation and conducting probe methods respectively. ZnO nanostructures are much harder than their bulk. The hardness of ZnO pyramids obtained by nanoindentation is 70 ± 10 GPa which is about one order more that of bulk ZnO. Besides, the nanostructures exhibit high sensitivity towards oxygen. A 70% increase in the resistance of ZnO nanostructures is observed when exposed to oxygen atmosphere.

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