Distributed temperature sensor combining centimeter resolution with hundreds of meters sensing range

Area of Science:

• Physics
• Optical Engineering
• Materials Science

Background:

• Distributed temperature sensing (DTS) is crucial for monitoring environments.
• Existing DTS systems face limitations in spatial resolution and accuracy over long distances.
• Advancements in photon detection and fiber optics are key to improving DTS.

Purpose of the Study:

• To develop a Raman distributed temperature sensor with enhanced spatial resolution and temperature accuracy.
• To investigate the performance limitations of the sensor concerning fiber length and integration time.
• To explore potential applications of the developed DTS technology.

Main Methods:

• Utilized standard telecom single-mode fibers.
• Employed polarization-independent superconducting nanowire single-photon detectors (SSPDs).
• Implemented Raman scattering principles for temperature measurement.

Main Results:

• Achieved 3 cm spatial resolution and 1.5 °C temperature accuracy on a 5 m fiber with 1-minute integration.
• Demonstrated that spatial resolution is limited by laser pulse width, not the detector.
• Identified chromatic dispersion and reduced laser repetition rate as factors affecting performance on longer fibers (e.g., 10 cm and 8 °C resolution on 500 m fiber with 3-minute integration).

Conclusions:

• The developed Raman DTS system offers centimetric spatial resolution over hundreds of meters.
• The technology shows promise for 2D and 3D temperature mapping in complex systems.
• Potential applications include electronic devices, particle detectors, and aerospace instrumentation.