Characterization of Ring Resonator Structures for Applications in Photonic Thermometry

Abstract

We have systematically examined the impact of structural parameters on silicon ring resonator-based photonic temperature sensor's performance by systematically varying the ring radius, waveguide width and gap separating the ring and waveguide.

Fiber Bragg Grating Based Thermometry

“…These fundamental limitations of resistance devices have produced considerable interest in the development of photonic temperature sensors as an alternative to resistance thermometers as they have the potential to leverage advances in frequency metrology to provide greater temperature sensitivity while being robust against mechanical shock and electromagnetic interference. [3][4][5][6][7][8][9][10] The vast and varied application landscape for temperature measurement has spawned a host of photonic temperature sensing solutions. The proposed sensor technologies range from temperature sensitive dyes [11], polymers [9,12,13] to silicon photonics such as ring resonators [4,5,7].…”

“…[3][4][5][6][7][8][9][10] The vast and varied application landscape for temperature measurement has spawned a host of photonic temperature sensing solutions. The proposed sensor technologies range from temperature sensitive dyes [11], polymers [9,12,13] to silicon photonics such as ring resonators [4,5,7]. Fiber Bragg grating (FBG) based temperature sensors have already been commercially introduced as photonic alternative to resistance thermometry.…”

Towards replacing resistance thermometry with photonic thermometry

“…Recently, we undertook a systematic survey of ring resonator parameter space that aimed to optimize the device performance while achieving consistent results. [21,22] Our results suggest that consistently high performance temperature sensors are obtained from the zone of stability (waveguide width > 600 nm, air gap  130 nm and ring radius > 10 m) such that quality factors are consistently 10 4 and the temperature sensitivity is consistently in the 70 pm/K to 85 pm/K range. [22] For evanescently coupled devices, over the temperature range of 293 K to 418 K, the fit residual varies between 170 mK to 30 mK.…”

“…[21,22] Our results suggest that consistently high performance temperature sensors are obtained from the zone of stability (waveguide width > 600 nm, air gap  130 nm and ring radius > 10 m) such that quality factors are consistently 10 4 and the temperature sensitivity is consistently in the 70 pm/K to 85 pm/K range. [22] For evanescently coupled devices, over the temperature range of 293 K to 418 K, the fit residual varies between 170 mK to 30 mK. Although comparison of the same device fabricated across different chips in the same batch reveals significant variation in temperature response, our results suggest that with better process control it is possible to achieve device interchangeability over a 200 mK tolerance band i.e.…”

Emerging technologies in the field of thermometry

“…At present routine fabrication imperfections and difficulty in procuring uniform thickness wafers limit device interchangeability to 200 mK uncertainty around room temperature [148]. At an individual device level, measurements using side-of-fringe constant power mode, it has been shown that a noise floor below 100 µK is achieved using a free running laser [26].…”