High-resolution slow-light fiber Bragg grating temperature sensor with phase-sensitive detection.

This Letter reports a slow-light fiber Bragg grating (FBG) temperature sensor with a record temperature resolution of ∼0.3  m°C/√Hz, a drift of only ∼1  m°C over the typical duration of a measurement (∼30  s), and negligible self-heating. This sensor is particularly useful for applications requiring the detection of very small temperature changes, such as radiation-balanced lasers and the measurement of small absorptive losses using calorimetry. The sensor performance is demonstrated by measuring the heat generated in a pumped Yb-doped fiber. The sensor is also used to measure the slow-light FBG's very weak internal absorption loss (0.02  m-1), which is found to be only ∼2% of the total loss.

[1]  A. Kersey,et al.  Fiber-optic Bragg-grating differential-temperature sensor , 1992, IEEE Photonics Technology Letters.

[2]  Raman Kashyap,et al.  Laser-induced cooling of a Yb:YAG crystal in air at atmospheric pressure. , 2013, Optics express.

[3]  Yunjiang Rao,et al.  Dual-cavity interferometric wavelength-shift detection for in-fiber Bragg grating sensors. , 1996, Optics letters.

[4]  Kazuya Saito,et al.  Influences of Yb3+ ion concentration on the spectroscopic properties of silica glass , 2008 .

[5]  Michel J. F. Digonnet,et al.  Slow light in fiber Bragg gratings and its applications , 2016 .

[6]  Michael A. Davis,et al.  Fiber grating sensors , 1997 .

[7]  Michel J. F. Digonnet,et al.  Measuring attostrains in a slow-light fiber Bragg grating , 2016, SPIE OPTO.

[8]  B. Ipson,et al.  High-temperature sensing using surface relief fiber Bragg gratings , 2005, IEEE Photonics Technology Letters.

[9]  David E McClelland,et al.  Demonstration of a passive subpicostrain fiber strain sensor. , 2005, Optics letters.

[10]  G. Ball,et al.  Fiber laser source/analyzer for Bragg grating sensor array interrogation , 1994 .

[11]  Michel J. F. Digonnet,et al.  Thermal effects in doped fibers , 1998 .

[12]  Réal Vallée,et al.  Observation of ~20 ns group delay in a low-loss apodized fiber Bragg grating. , 2014, Optics letters.

[13]  J Carrier,et al.  High mechanical strength fiber Bragg gratings made with infrared femtosecond pulses and a phase mask. , 2014, Optics letters.

[14]  Fan Yang,et al.  Measurement of local temperature increments induced by cultured HepG2 cells with micro-thermocouples in a thermally stabilized system , 2017, Scientific Reports.

[15]  E. Black.  An introduction to Pound–Drever–Hall laser frequency stabilization , 2001 .