Temperature Sensor Based on an Asymmetric Two-Hole Fiber Using a Sagnac Interferometer

Table 1

Comparison of recent temperature sensors using different birefringent fibers.

	Technique	Sensitivity (nm/°C)	Operation range (°C)	Length (cm)
Filled fibers
[22]	Liquid-sealed photonic crystal fiber (PCF) in-line nonpolarimetric modal interferometer	−0.166	23.7–66.1	1.15
[23]	Ethanol-filled PCF combined with a fully collapsed splicing with single-mode fibers	−0.35	20.0–50.0	3.25
[24]	Fully liquid-filled PCF Mach-Zehnder interferometer	−1.83	23.2–58.2	7.5
[29]	Selectively filled polarization-maintaining PCF (PM-PCF) in a Sagnac interferometer configuration	2.58	25.0–42.0	11.7
[21]	Alcohol-filled PCF loop mirror	6.6	8.0–20.0	6.1
		6.2	20.0–34.0
[8]	SLI based on a side-hole PCF filled with metal
	In-filled	−9.0	22.4–46	20
	Bi-filled	−1.80	21.6–70.7
Unfilled fibers
[36]	PANDA fiber in a SL configuration	−1.46	40–60	6
[34]	Bow-tie fiber in a SL configuration	−1.23	45–75	0.356
This work	ATHF using a SL, based on the birefringence change induced by the temperature difference between the air holes and the silica fiber	2.2	20.0–40.0	200
In this work	PM fiber in a SL configuration	−2.54	20.0–80.0	10