Hydrogen is widely used in industrial production, clinical medicine, and as fuel. Hydrogen becomes explosive when the hydrogen-air mixture ranges from 4 to 76 vol%; thus, a rapid hydrogen concentration...
Nanomechanical sensors made from suspended graphene are
sensitive
to pressure changes. However, these devices typically function by
obtaining an electrical signal based on the static displacement of
a suspended graphene membrane and so, in practice, have limited sensitivity
and operational range. The present work demonstrates an optomechanical
Au/graphene membrane-based gas pressure sensor with ultrahigh sensitivity.
This sensor comprises a suspended Au/graphene membrane appended to
a section of hollow-core fiber to form a sealed Fabry–Pérot
cavity. In contrast to conventional nanomechanical pressure sensors,
pressure changes are monitored via resonant sensing with an optical
readout. A miniature pressure sensor based on this principle was able
to detect an ultrasmall pressure difference of 1 × 10–7 mbar in the ultrahigh-vacuum region with a pressure range of 4.1
× 10–5 to 8.3 × 10–6 mbar. Furthermore, this pressure sensor can work over an extended
pressure range of 7 × 10–6 mbar to 1000 mbar
at room temperature, outperforming commercial pressure sensors. Similar
results were obtained using both the fundamental and higher-order
resonant frequencies but with the latter providing improved sensitivity.
This sensor has a wide range of potential applications, including
indoor navigation, altitude monitoring, and motion detection.
A gas pressure sensor, based on a phase-shifted fiber Bragg grating (PS-FBG) modulated by a hollow cavity, is proposed and demonstrated in this Letter. The device was fabricated by fusing a hollow-core fiber (HCF) between two single-mode fibers (SMFs) exhibiting FBGs that were inscribed using line-by-line femtosecond (fs) laser etching. A pair of micro-channels were drilled orthogonally into the HCF using an fs laser to allow the argon gas to get in and out freely. Such a sensor exposes a high spectrum finesse, e.g., a
Q
-factor of
∼
7302
, which can be improved by increasing the grating pitch quantity. Furthermore, a high gas pressure sensitivity of 1.22 nm/Mpa is obtained, corresponding the improved sensor with a grating pitch quantity of 300 and a hollow cavity length of 88.3 µm. In addition, the device exhibited a low temperature sensitivity of 8.92 pm/°C.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.