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Unlike traditional sensing schemes which rely on discrete point sensors that perform measurements at predetermined positions, distributed optical fiber sensing is a general technique that enables to continuously gather information (typically temperature an ...

Fibre optics sensors have been identified as very good candidates for environmental monitoring inside the silicon detectors operated at CERN’s Large Hadron Collider. In this study, we present the results from the first highly sensitive relative humidity di ...

High electron-injection efficiency is important for further development of dye-sensitized solar cells (DSSCs). Different electron acceptors have different electron-injection capabilities, which affect device performance. Herein, the effects of two organic ...

The spectral properties of the Rayleigh backscattered traces measured by a phase-sensitive optical time-domain reflectometer (øOTDR) with direct detection are theoretically and experimentally analyzed. The spectrum of the measured øOTDR signal is found to ...

The phase change of back-scattered light due to external perturbations is retrieved in coherent Rayleigh-based distributed sensors by estimating the frequency shift (FS) between the traces of different measurements. The uncertainty associated with the esti ...

A distributed and dynamic strain sensing system based on frequency-scanning phase-sensitive optical time domain reflectometry is proposed and demonstrated. By utilizing an RF pulse scheme with a fast arbitrary waveform generator, a train of optical pulses ...

A highly sensitive distributed pressure sensing system (< 20 hPa) based on phasesensitive optical time-domain reflectometry with side air holes fiber is proposed, reaching a sensing range of 1.05 km with a 5 cm spatial resolution ...

A molecular understanding of the interactions between two-dimensional (2D) layered materials and liquids is crucial for nanofluidics, catalysis, and solution-based 2D material processing. Among 2D materials, hexagonal boron nitride (hBN) has a number of ou ...

Brillouin scattering in gas shows unmatched gain properties in hollow-core optical fibers filled at high pressure. Here, the gain characteristics are studied for two common gases, namely, N2 and CO2, which show distinct features and are compared to expecte ...

Large frequency shift errors induced by cross-correlation are investigated in Rayleigh-based distributed sensing. A least mean square method is proposed to reduce those errors, thus increasing the reliability and extending the measurand range. ...

Distributed temperature sensing with 10 dB back-reflection-enhanced fiber is performed based on φ-OTDR. While the temperature sensitivity of such fibers is similar to that of standard single-mode fibers, a 3-times higher temperature resolution is observed. ...

Commonly, the frequency shift of back-reflection spectra is the key parameter to measure quantitatively local temperature or strain changes in frequency-scanned Rayleigh-based distributed fiber sensors. Cross-correlation is the most common method to estima ...

A distributed dynamic strain sensing system based on frequency-scanned phase-sensitive optical time domain reflectometry is proposed and demonstrated. It demonstrates a record spatial resolution of 20 cm, compared with other direct-detection dynamic strain ...

A closed-loop servo control based on the gain ratio of two probing frequencies is proposed for fast BOTDA, where the feedback is independent of probe and pump loss, making it robust in harsh environment. ...

In this paper, a long-distance distributed pressure sensing system based on a special fiber and using frequency-scanned phase-sensitive optical time-domain reflectometry is proposed. The fiber shows high pressure sensitivity (159 MHz/bar) and low loss (3 d ...

We propose a distributed hydrogen sensing system based on ϕ-OTDR and a novel coating configuration with fiber adhesively bonding to palladium foils. An ultra-high sensitivedistributed hydrogen sensing with 5 cm spatial resolution is demonstrated ...

Aqueous interfaces are responsible for a plethora of processes. At the nanoscale, interfaces are overwhelmingly influenced by finite volume effects that are thought to impact both molecular level and macroscopic properties. Here, finite volume effects are investigated using electrophoretic mobility and vibrational sum frequency scattering of water nanodroplets in oil and oil nanodroplets in water, made from the same chemicals. Notably, there is a substantial difference in the orientational ordering of water

An analytical expression to estimate the uncertainty on the frequency shift in ϕ-OTDR systems is established and confirmed by actual data. ...

Gases turn out to be a very attractive medium for optical fiber sensing, showing highly flexible possibilities though widely unexploited so far. A new era opens for fiber sensing, exploiting the unprecedented potentialities of fluids. ...

Li Zhang

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Distributed optical fiber sensing based on frequency-scanned phase-sensitive optical time-domain reflectometry

A kilometre-range distributed relative humidity sensor

Electron-Withdrawing Anchor Group of Sensitizer for Dye-Sensitized Solar Cells, Cyanoacrylic Acid, or Benzoic Acid?

Spectral Properties of the Signal in Phase-Sensitive Optical Time-Domain Reflectometry with Direct Detection

On the Measurement Accuracy of Coherent Rayleigh-based Distributed Sensors

Distributed and dynamic strain sensing with high spatial resolution and large measurable strain range

Fully distributed pressure sensing with ultra-high-sensitivity using side-hole fibers

Sum-Frequency Scattering Spectroscopy Reveals the Charging Mechanism and Surface Structure of hBN Nanoflakes in Solution

Study of backward Brillouin scattering in gas-filled anti-resonant fibers

Rayleigh-Based Distributed Optical Fiber Sensing Using Least Mean Square Similarity

Distributed Temperature Sensing Based on φ-OTDR Using Back-reflection-enhanced Fiber

[Erratum] Study of backward Brillouin scattering in gas-filled anti-resonant fibers (vol 8, 086104, 2023)

Analysis and Reduction of Large Errors in Rayleigh-based Distributed Sensor

High spatial resolution distributed and dynamic strain sensing using direct detection

Closed-loop technique using gain balance for fast Brillouin Optical Time-Domain Analysis

Long-distance distributed pressure sensing based on frequency-scanned phase-sensitive optical time-domain reflectometry

Distributed hydrogen monitoring with phase-sensitive optical time-domain reflectometry

Finite Volume Effects in Water Nanodroplets: A Molecular Level Investigation

Analytical prediction of the final error due to noise in a ϕ-OTDR system

New Avenues in Optical Fiber Sensing Using Gas